WO2012165039A1 - 画像処理装置及び画像処理方法 - Google Patents
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- H04N19/17—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being an image region, e.g. an object
- H04N19/176—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being an image region, e.g. an object the region being a block, e.g. a macroblock
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Definitions
- the present disclosure relates to an image processing apparatus and an image processing method.
- compression is intended to efficiently transmit or store digital images, and compresses the amount of information of an image using orthogonal transform such as discrete cosine transform and motion compensation, for example, using redundancy unique to the image.
- orthogonal transform such as discrete cosine transform and motion compensation
- Technology is widespread.
- H.264 developed by ITU-T.
- Image encoding devices and image decoding devices compliant with standard technologies such as the 26x standard or the MPEG-y standard established by the Moving Picture Experts Group (MPEG), store and distribute images by broadcast stations, and receive images by general users It is widely used in various situations such as storage.
- MPEG Moving Picture Experts Group
- the 26x standard (ITU-T Q6 / 16 VCEG) is a standard originally developed for the purpose of encoding suitable for communication applications such as videophone or videoconferencing. H.
- the 26x standard is known to be able to realize a higher compression ratio while requiring a larger amount of calculation for encoding and decoding than the MPEG-y standard.
- Joint Model of Enhanced-Compression Video Coding as part of MPEG4 activities Based on the 26x standard, a standard that can achieve a higher compression ratio has been established by incorporating new functions. This standard was approved in March 2003 by H.264. H.264 and MPEG-4 Part 10 (Advanced Video Coding; AVC) have become international standards.
- Intra prediction is a technique for reducing the amount of encoded information by using the correlation between adjacent blocks in an image and predicting the pixel values in a block from the pixel values of other adjacent blocks. .
- intra prediction is possible for all pixel values.
- intra prediction may be performed using a block of 4 ⁇ 4 pixels, 8 ⁇ 8 pixels, or 16 ⁇ 16 pixels as one processing unit (ie, prediction unit (PU)).
- PU prediction unit
- HEVC High Efficiency Video Coding
- the size of the prediction unit is about to be expanded to 32 ⁇ 32 pixels and 64 ⁇ 64 pixels.
- an optimal prediction mode for predicting a pixel value of a prediction target block is selected from a plurality of prediction modes.
- the prediction mode can typically be distinguished by the prediction direction from the reference pixel to the prediction target pixel.
- H.M. In H.264 / AVC, when predicting a color difference component, four prediction modes of average value prediction, horizontal prediction, vertical prediction, and plane prediction can be selected.
- LM linear model
- a pixel function of a color difference component is predicted using a linear function of a luminance component that is dynamically constructed as a prediction function.
- Non-Patent Document 2 the processing cost required for constructing an LM mode prediction function increases as the number of reference pixels increases. For this reason, in HEVC in which the size of the prediction unit is expanded to 64 ⁇ 64 pixels at the maximum, the processing cost that increases due to the adoption of the LM mode may degrade the encoding and decoding performance.
- a prediction unit that generates a prediction value of a color difference component of a pixel of a decoded image using a function of a value of a corresponding luminance component, and a coefficient of the function used by the prediction unit, Image processing comprising: a coefficient calculation unit that calculates with reference to pixels around a block to which the pixel belongs; and a control unit that controls a ratio of the number of reference pixels used by the coefficient calculation unit to the block size of the block
- the image processing apparatus can typically be realized as an image decoding apparatus that decodes an image.
- the predicted value of the color difference component of the pixel of the image to be decoded is generated using a function of the value of the corresponding luminance component, and the coefficient of the function is calculated for the block to which the pixel belongs.
- An image processing method includes calculating with reference to surrounding pixels and controlling a ratio of the number of reference pixels used in calculating the coefficient to the block size of the block.
- a prediction unit that generates a prediction value of a color difference component of a pixel of an image to be encoded using a function of a value of a corresponding luminance component, and the function used by the prediction unit
- a coefficient calculation unit that calculates a coefficient with reference to pixels around the block to which the pixel belongs, and a control unit that controls a ratio of the number of reference pixels used by the coefficient calculation unit to the block size of the block;
- the image processing apparatus can typically be realized as an image encoding apparatus that encodes an image.
- the predicted value of the color difference component of the pixel of the image to be encoded is generated using a function of the value of the corresponding luminance component, and the coefficient of the function is set to a block to which the pixel belongs
- An image processing method includes calculating with reference to neighboring pixels and controlling the ratio of the number of reference pixels used in calculating the coefficient to the block size of the block.
- the prediction unit that performs intra prediction of the color difference component of the image using the luminance component of the image to be decoded, and the reference pixel that is referred to when the intra prediction is performed by the prediction unit are variable.
- an image processing apparatus including a control unit that automatically controls the image processing apparatus.
- the image processing apparatus may be realized as an image encoding apparatus that encodes an image, or may be realized as an image decoding apparatus that decodes an image.
- intra prediction of the color difference component of the image is performed using the luminance component of the image to be decoded, and a reference pixel referred to when the intra prediction of the color difference component is performed is variable.
- FIG. 26 is a first explanatory diagram for explaining a thinning rate different from the example of FIG. 25.
- FIG. 26 is a second explanatory diagram for explaining a thinning rate different from the example of FIG. 25.
- FIG. 26 is a third explanatory diagram for explaining a thinning rate different from the example of FIG. 25. It is explanatory drawing for demonstrating the 1st example of a response
- FIG. 1 is a block diagram illustrating an example of a configuration of an image encoding device 10 according to an embodiment.
- an image encoding device 10 includes an A / D (Analogue to Digital) conversion unit 11, a rearrangement buffer 12, a subtraction unit 13, an orthogonal transformation unit 14, a quantization unit 15, a lossless encoding unit 16, The accumulation buffer 17, rate control unit 18, inverse quantization unit 21, inverse orthogonal transform unit 22, addition unit 23, deblock filter 24, frame memory 25, selectors 26 and 27, motion search unit 30, and intra prediction unit 40 Prepare.
- a / D Analogue to Digital
- the A / D converter 11 converts an image signal input in an analog format into image data in a digital format, and outputs a series of digital image data to the rearrangement buffer 12.
- the rearrangement buffer 12 rearranges the images included in the series of image data input from the A / D conversion unit 11.
- the rearrangement buffer 12 rearranges the images according to the GOP (Group of Pictures) structure related to the encoding process, and then outputs the rearranged image data to the subtraction unit 13, the motion search unit 30, and the intra prediction unit 40. To do.
- GOP Group of Pictures
- the subtraction unit 13 is supplied with image data input from the rearrangement buffer 12 and predicted image data input from the motion search unit 30 or the intra prediction unit 40 described later.
- the subtraction unit 13 calculates prediction error data that is a difference between the image data input from the rearrangement buffer 12 and the prediction image data, and outputs the calculated prediction error data to the orthogonal transformation unit 14.
- the orthogonal transform unit 14 performs orthogonal transform on the prediction error data input from the subtraction unit 13.
- the orthogonal transformation performed by the orthogonal transformation part 14 may be discrete cosine transformation (Discrete Cosine Transform: DCT) or Karoonen-Labe transformation, for example.
- the orthogonal transform unit 14 outputs transform coefficient data acquired by the orthogonal transform process to the quantization unit 15.
- the quantization unit 15 is supplied with transform coefficient data input from the orthogonal transform unit 14 and a rate control signal from the rate control unit 18 described later.
- the quantizing unit 15 quantizes the transform coefficient data and outputs the quantized transform coefficient data (hereinafter referred to as quantized data) to the lossless encoding unit 16 and the inverse quantization unit 21. Further, the quantization unit 15 changes the bit rate of the quantized data input to the lossless encoding unit 16 by switching the quantization parameter (quantization scale) based on the rate control signal from the rate control unit 18.
- the lossless encoding unit 16 generates an encoded stream by performing a lossless encoding process on the quantized data input from the quantization unit 15.
- the lossless encoding by the lossless encoding unit 16 may be variable length encoding or arithmetic encoding, for example. Further, the lossless encoding unit 16 multiplexes information related to intra prediction or information related to inter prediction input from the selector 27 in the header region of the encoded stream. Then, the lossless encoding unit 16 outputs the generated encoded stream to the accumulation buffer 17.
- the accumulation buffer 17 temporarily accumulates the encoded stream input from the lossless encoding unit 16 using a storage medium such as a semiconductor memory. Then, the accumulation buffer 17 outputs the accumulated encoded stream to a transmission unit (not shown) (for example, a communication interface or a connection interface with a peripheral device) at a rate corresponding to the bandwidth of the transmission path.
- a transmission unit for example, a communication interface or a connection interface with a peripheral device
- the rate control unit 18 monitors the free capacity of the accumulation buffer 17. Then, the rate control unit 18 generates a rate control signal according to the free capacity of the accumulation buffer 17 and outputs the generated rate control signal to the quantization unit 15. For example, the rate control unit 18 generates a rate control signal for reducing the bit rate of the quantized data when the free capacity of the storage buffer 17 is small. For example, when the free capacity of the accumulation buffer 17 is sufficiently large, the rate control unit 18 generates a rate control signal for increasing the bit rate of the quantized data.
- the inverse quantization unit 21 performs an inverse quantization process on the quantized data input from the quantization unit 15. Then, the inverse quantization unit 21 outputs transform coefficient data acquired by the inverse quantization process to the inverse orthogonal transform unit 22.
- the inverse orthogonal transform unit 22 restores the prediction error data by performing an inverse orthogonal transform process on the transform coefficient data input from the inverse quantization unit 21. Then, the inverse orthogonal transform unit 22 outputs the restored prediction error data to the addition unit 23.
- the adding unit 23 generates decoded image data by adding the restored prediction error data input from the inverse orthogonal transform unit 22 and the predicted image data input from the motion search unit 30 or the intra prediction unit 40. . Then, the addition unit 23 outputs the generated decoded image data to the deblock filter 24 and the frame memory 25.
- the deblocking filter 24 performs a filtering process for reducing block distortion that occurs during image coding.
- the deblocking filter 24 removes block distortion by filtering the decoded image data input from the adding unit 23, and outputs the decoded image data after filtering to the frame memory 25.
- the frame memory 25 stores the decoded image data input from the adder 23 and the decoded image data after filtering input from the deblock filter 24 using a storage medium.
- the selector 26 reads out the decoded image data after filtering used for inter prediction from the frame memory 25 and supplies the read out decoded image data to the motion search unit 30 as reference image data.
- the selector 26 reads out decoded image data before filtering used for intra prediction from the frame memory 25 and supplies the read decoded image data to the intra prediction unit 40 as reference image data.
- the selector 27 In the inter prediction mode, the selector 27 outputs the prediction image data as a result of the inter prediction output from the motion search unit 30 to the subtraction unit 13 and outputs information related to the inter prediction to the lossless encoding unit 16. Further, in the intra prediction mode, the selector 27 outputs predicted image data as a result of the intra prediction output from the intra prediction unit 40 to the subtraction unit 13 and outputs information related to the intra prediction to the lossless encoding unit 16. . The selector 27 switches between the inter prediction mode and the intra prediction mode according to the size of the cost function value output from the motion search unit 30 and the intra prediction unit 40.
- the motion search unit 30 performs inter prediction processing (interframe prediction processing) based on image data to be encoded (original image data) input from the reordering buffer 12 and decoded image data supplied via the selector 26. )I do. For example, the motion search unit 30 evaluates the prediction result in each prediction mode using a predetermined cost function. Next, the motion search unit 30 selects the prediction mode with the smallest cost function value, that is, the prediction mode with the highest compression rate, as the optimum prediction mode. In addition, the motion search unit 30 generates predicted image data according to the optimal prediction mode. Then, the motion search unit 30 outputs prediction mode information indicating the selected optimal prediction mode, information on inter prediction including motion vector information and reference image information, a cost function value, and predicted image data to the selector 27.
- inter prediction processing interframe prediction processing
- the intra prediction unit 40 performs an intra prediction process for each block set in the image based on the original image data input from the rearrangement buffer 12 and the decoded image data as reference image data supplied from the frame memory 25. I do. Then, the intra prediction unit 40 outputs information related to intra prediction including the prediction mode information indicating the optimal prediction mode and the size related information, the cost function value, and the predicted image data to the selector 27.
- the prediction modes selectable by the intra prediction unit 40 include a linear model (LM) mode for color difference components in addition to the existing intra prediction modes. Unlike the LM mode described in Non-Patent Document 2, the LM mode in this embodiment has a feature that the ratio of the number of reference pixels to the block size can be changed. Such intra prediction processing by the intra prediction unit 40 will be described in detail later.
- FIG. 2 is a block diagram illustrating an example of a detailed configuration of the intra prediction unit 40 of the image encoding device 10 illustrated in FIG. 1.
- the intra prediction unit 40 includes a prediction control unit 42, a coefficient calculation unit 44, a prediction unit 46, and a mode determination unit 48.
- the prediction control unit 42 controls the intra prediction process in the intra prediction unit 40.
- the prediction control unit 42 executes the intra prediction process for the luminance component (Y) for each coding unit (CU: Coding Unit), and then executes the intra prediction process for the color difference components (Cb, Cr).
- the prediction control unit 42 causes the prediction unit 46 to generate a prediction pixel value of each pixel in a plurality of prediction modes, and causes the mode determination unit 48 to determine the optimal prediction mode of the luminance component.
- the arrangement of prediction units within the coding unit is also determined.
- the prediction control unit 42 causes the prediction unit 46 to generate a prediction pixel value of each pixel in a plurality of prediction modes for each prediction unit, and causes the mode determination unit 48 to optimally predict the color difference component. To determine.
- Prediction mode candidates for luminance components are H.264. It may be a prediction mode employed in an existing image coding method such as H.264 / AVC, and may include other prediction modes. Prediction mode candidates for color difference components may also include prediction modes employed in existing image coding schemes. Further, the prediction mode candidates for the color difference components include the LM mode described above. In the method described in Non-Patent Document 2, the ratio of the number of reference pixels to the block size when calculating the coefficient of the prediction function in the LM mode is constant. Therefore, as the block size increases, the number of reference pixels increases accordingly. On the other hand, in the present embodiment, the prediction control unit 42 variably controls the ratio.
- the block size here means the size of the prediction unit in principle.
- the above-described ratio controlled by the prediction control unit 42 that is, the ratio of the number of reference pixels to the block size is referred to as a “reference ratio”.
- the control of the reference ratio by the prediction control unit 42 can typically be performed according to the block size.
- the prediction control unit 42 may control the reference ratio according to a chroma format that affects the block size of the color difference component corresponding to the prediction unit.
- the prediction control unit 42 may control the reference ratio according to a parameter (for example, a profile or a level) that defines the capability of the apparatus related to image encoding and decoding. A plurality of scenarios of reference ratio control by the prediction control unit 42 will be described in detail later.
- the coefficient calculation unit 44 calculates the coefficient of the prediction function used by the prediction unit 46 in the LM mode with reference to the pixels around the prediction unit to which the prediction target pixel belongs, that is, the reference pixel.
- the prediction function used by the prediction unit 46 is typically a linear function of luminance component values.
- the number of reference pixels referred to by the coefficient calculation unit 44 when calculating the coefficient of the prediction function is controlled by the prediction control unit 42 as described above.
- the prediction unit 46 predicts the pixel value of the luminance component and the pixel value of the color difference component of the pixel to be predicted according to various prediction mode candidates under the control of the prediction control unit 42.
- An example of prediction mode candidates used by the prediction unit 46 will be described in detail later.
- Predicted image data generated as a result of prediction by the prediction unit 46 is output to the mode determination unit 48 for each prediction mode.
- the mode determination unit 48 calculates a cost function value for each prediction mode based on the original image data input from the rearrangement buffer 12 and the predicted image data input from the prediction unit 46. Then, the mode determination unit 48 determines the optimal prediction mode for the luminance component and the arrangement of the prediction unit in the coding unit based on the calculated cost function value. Similarly, the mode determination unit 48 determines an optimal prediction mode for the color difference component based on the cost function value for the color difference component. Then, the mode determination unit 48 predicts image data including information related to intra prediction including prediction mode information indicating the determined optimal prediction mode and size related information, cost function values, and prediction pixel values of luminance components and color difference components. Is output to the selector 27.
- the size related information output from the mode determination unit 48 may include information specifying a chroma format in addition to information for specifying the size of each prediction unit.
- Prediction mode candidates for luminance components are The prediction mode may be a prediction mode employed in an existing image coding method such as H.264 / AVC. 3 to 5 are explanatory diagrams for explaining such prediction mode candidates when the size of the prediction unit is 4 ⁇ 4 pixels.
- FIG. 4 schematically shows prediction directions corresponding to the mode numbers.
- lower case alphabets a to p represent pixel values of each pixel (that is, a prediction target pixel) in a prediction unit of 4 ⁇ 4 pixels.
- the prediction direction in mode 0 is the vertical direction.
- the prediction direction in mode 1 is the horizontal direction.
- Mode 2 represents DC prediction (average value prediction).
- the prediction direction in mode 3 is diagonally lower left.
- the prediction direction in mode 4 is diagonally lower right.
- the prediction direction in mode 5 is vertical right.
- the prediction direction in mode 6 is horizontally below.
- the prediction direction in mode 7 is vertical left.
- the prediction direction in mode 8 is horizontal.
- mode 0 to mode 3 four types of prediction modes (mode 0 to mode 3) that can be used in a prediction unit of 16 ⁇ 16 pixels are shown.
- the prediction direction in mode 0 is the vertical direction.
- the prediction direction in mode 1 is the horizontal direction.
- Mode 2 represents DC prediction (average value prediction).
- Mode 3 represents planar prediction.
- the prediction mode for color difference components can be selected independently of the prediction mode for luminance components.
- FIG. 8 shows a prediction mode among the prediction mode candidates that can be used when the block size of the color difference component is 8 ⁇ 8 pixels.
- Four prediction modes (mode 0 to mode 3) employed in existing image coding schemes such as H.264 / AVC are shown.
- Mode 0 represents DC prediction (average value prediction).
- the predicted pixel value at the pixel position (x, y) is Pr C (x, y)
- the left eight reference pixel values are Re C ( ⁇ 1, n)
- the upper eight reference pixel values are Re C.
- (n, -1) means a color difference component.
- n is an integer of 0 or more and 7 or less.
- the predicted pixel value Pr C (x, y) is then calculated according to one of the following three formulas, depending on which reference pixel is available:
- the prediction direction in mode 1 is the horizontal direction, and the predicted pixel value Pr C (x, y) is calculated as follows:
- Prediction direction in Mode 2 is a vertical direction
- the predicted pixel value Pr C (x, y) is calculated as follows:
- Mode 3 represents planar prediction.
- the predicted pixel value Pr C (x, y) is calculated as follows:
- the LM mode described in the next section can be selected (for example, as mode 4) for the color difference component.
- the predicted pixel value for the color difference component is calculated using a linear function of the value of the corresponding luminance component.
- the prediction function used in the LM mode may be a linear linear function described in Non-Patent Document 2 as follows:
- Re L ′ (x, y) represents the value of the pixel position (x, y) after resampling of the luminance component of the decoded image (so-called reconstructed image).
- the resampling of the luminance component is performed when the resolution of the color difference component differs from the resolution of the luminance component depending on the chroma format. For example, when the chroma format is 4: 2: 0, the luminance component is resampled according to the following equation so that the number of pixels is halved in both the horizontal direction and the vertical direction.
- Re L (u, v) represents the value of the luminance component at the pixel position (u, v) before resampling.
- the luminance component is resampled so that the number of pixels is halved in the horizontal direction.
- the chroma format is 4: 4: 4, resampling of the luminance component is not performed.
- the coefficient ⁇ in the equation (1) is calculated according to the following equation (3). Further, the coefficient ⁇ of the equation (1) can be calculated according to the following equation (4).
- the size of the prediction unit (PU) is 16 ⁇ 16 pixels, and the chroma format is 4: 2: 0.
- the block size of the color difference component is 8 ⁇ 8 pixels.
- the size of the prediction unit (PU) is 8 ⁇ 8 pixels, and the chroma format is 4: 2: 0.
- the block size of the color difference component is 4 ⁇ 4 pixels.
- the prediction control unit 42 variably controls the number of reference pixels when the coefficient calculation unit 44 calculates the coefficient ⁇ and the coefficient ⁇ of the prediction function in the LM mode as described in the next section.
- the prediction control unit 42 controls the reference ratio, which is the ratio of the number of reference pixels to the block size, to be smaller as the block size is larger. Thereby, an increase in processing cost when the block size is increased is suppressed.
- the prediction control unit 42 may not change the reference ratio even if the block size is different when the block size is small enough that the processing cost does not become a problem.
- five exemplary scenarios of reference ratio control will be described with reference to FIGS. 10 to 18B.
- FIG. 10 is an explanatory diagram showing an example of the definition of the reference ratio in the first scenario.
- the reference ratio is “1: 1”.
- the reference ratio “1: 1” means that all the reference pixels as shown in FIG. 9A or 9B are used.
- the reference ratio is “1: 1”.
- the reference ratio is “2: 1”.
- the reference ratio “2: 1” means that only half of the reference pixels as shown in FIG. 9A or 9B are used. That is, the coefficient calculation unit 44 uses only the remaining reference pixels after thinning out half of the reference pixels when calculating the coefficients ⁇ and ⁇ .
- the chroma format is 4: 2: 0
- the chroma format is 4: 2: 2: 2
- FIG. 11A shows an example of reference pixel settings when the PU size is 16 ⁇ 16 pixels and the chroma format is 4: 2: 0.
- every other reference pixel of the color difference component and reference pixel of the luminance component are thinned out.
- the reference pixel number I L of the reference pixel number I C and the luminance component of the color difference component are both eight.
- the reference ratio is “4: 1”.
- the reference ratio “4: 1” means that only one quarter of the reference pixels as shown in FIG. 9A or 9B are used. That is, the coefficient calculation unit 44 uses only the remaining reference pixels after thinning out the three-fourth reference pixels when calculating the coefficients ⁇ and ⁇ .
- the chroma format is 4: 2: 0
- FIG. 11B shows an example of reference pixel settings when the PU size is 32 ⁇ 32 pixels and the chroma format is 4: 2: 0.
- the reference pixel number I L of the reference pixel number I C and the luminance component of the color difference component are both eight.
- the reference pixel number I is constant as long as the chroma format is the same. . Therefore, an increase in processing cost when the block size increases is suppressed. Further, by controlling the reference ratio so that the number of reference pixels is constant when the block size exceeds a predetermined size in this way, the coefficient calculation process in the coefficient calculation unit 44 is performed by a small common circuit or logic. It becomes possible to perform using. Thereby, an increase in circuit scale or logic scale can also be suppressed.
- the prediction accuracy of the LM mode is lowered due to the insufficient number of reference pixels.
- intra prediction is relatively difficult due to the complexity of the image content (that is, the spatial variation of the pixel value is severe)
- a smaller prediction unit is likely to be set in the image.
- by securing a sufficient number of reference pixels it is possible to prevent a decrease in prediction accuracy in the LM mode.
- the coefficient calculation unit 44 also serves as a thinning unit that thins out reference pixels that are referred to when intra prediction is performed in the LM mode with a reference ratio corresponding to the block size to be predicted.
- the coefficient calculation unit 94 of the image decoding device 60 described later.
- the number of reference pixels may be variably controlled by deriving one representative value from a plurality of reference pixel values instead of thinning out the reference pixels. For example, if the reference ratio is “4: 1”, an average value or a median value of the pixel values of four consecutive reference pixels may be used as one representative value.
- the process of thinning out the reference pixels is very easy to implement, but the prediction accuracy can be improved by using the representative values described above.
- FIG. 12 is an explanatory diagram showing an example of the definition of the reference ratio in the second scenario.
- the prediction control unit 42 controls the reference ratio according to the chroma format in addition to the size of the prediction unit.
- the prediction control unit 42 calculates a first reference ratio that is a ratio of the number of left reference pixels to a vertical size and a second reference ratio that is a ratio of the upper reference pixels to a horizontal size. Control separately.
- the vertical reference ratio and the horizontal reference ratio are both “1: 1”. .
- the vertical reference ratio is “2: 1” and the horizontal reference ratio is “1: 1”.
- the vertical reference ratio and the horizontal reference ratio are both “2: 1”.
- the prediction unit size is 8 ⁇ 8 pixels and the chroma format is 4: 2: 2
- the vertical reference ratio is “2: 1”
- both the reference ratio in the vertical direction and the reference ratio in the horizontal direction are “2: 1”.
- FIG. 13A shows an example of reference pixel settings when the PU size is 8 ⁇ 8 pixels and the chroma format is 4: 2: 0.
- the reference pixel for the color difference component and the reference pixel for the luminance component are not thinned out.
- the reference pixel number I L of the reference pixel number I C and the luminance component of the color difference component are both eight.
- FIG. 13B shows an example of reference pixel settings when the PU size is 8 ⁇ 8 pixels and the chroma format is 4: 2: 2.
- every other reference pixel in the vertical direction of the color difference component and the luminance component is thinned out.
- the reference pixel number I L of the reference pixel number I C and the luminance component of the color difference component are both eight.
- FIG. 13C shows an example of reference pixel settings when the PU size is 8 ⁇ 8 pixels and the chroma format is 4: 4: 4.
- every other reference pixel in the vertical and horizontal directions of the color difference component and the luminance component is thinned out.
- the reference pixel number I L of the reference pixel number I C and the luminance component of the color difference component are both eight.
- both the reference ratio in the vertical direction and the reference ratio in the horizontal direction are “2: 1”.
- the prediction unit size is 16 ⁇ 16 pixels and the chroma format is 4: 2: 2
- the vertical reference ratio is “4: 1”
- the horizontal reference ratio is “2: 1”.
- the size of the prediction unit is 16 ⁇ 16 pixels and the chroma format is 4: 4: 4: 4: 4: 4
- both the reference ratio in the vertical direction and the reference ratio in the horizontal direction are “4: 1”.
- FIG. 13D shows an example of reference pixel settings when the PU size is 16 ⁇ 16 pixels and the chroma format is 4: 2: 0.
- every other vertical and horizontal reference pixels of the color difference component and the luminance component are thinned out.
- the reference pixel number I L of the reference pixel number I C and the luminance component of the color difference component are both eight.
- both the reference ratio in the vertical direction and the reference ratio in the horizontal direction are “4: 1”.
- the prediction unit size is 32 ⁇ 32 pixels and the chroma format is 4: 2: 2
- the vertical reference ratio is “8: 1” and the horizontal reference ratio is “4: 1”.
- the size of the prediction unit is 32 ⁇ 32 pixels and the chroma format is 4: 4: 4: 4: 4: 4
- both the reference ratio in the vertical direction and the reference ratio in the horizontal direction are “8: 1”.
- the prediction control unit 42 controls the reference ratio such that the higher the resolution of the color difference component represented by the chroma format, the smaller the reference ratio. .
- the prediction control unit 42 performs the vertical direction so that the number of reference pixels on the left side of the block is equal to the number of reference pixels on the block.
- the horizontal reference ratio are controlled separately. Thereby, it is possible to make the reference pixel number the same in a plurality of cases where the chroma formats are different from each other.
- the coefficient calculation process in the coefficient calculation unit 44 can be performed using a common circuit or logic regardless of the chroma format.
- efficient implementation of the circuit or logic is facilitated.
- FIG. 14 is an explanatory diagram showing an example of the definition of the reference ratio in the third scenario.
- the prediction control unit 42 has a first reference ratio that is a ratio of the number of left reference pixels to a vertical size and a second reference ratio that is a ratio of the upper reference pixels to the horizontal size. The reference ratio is controlled separately.
- the prediction control unit 42 controls these reference ratios so that the vertical reference ratio is equal to or lower than the horizontal reference ratio for the same block size.
- the reference ratios in the vertical direction and the horizontal direction are both “1: 1”.
- the chroma format is 4: 2: 0
- the reference ratio in the vertical direction is “2: 1”, and the reference ratio in the horizontal direction is “1: 1”.
- FIG. 15A shows an example of reference pixel settings when the PU size is 8 ⁇ 8 pixels and the chroma format is 4: 2: 0.
- the reference pixels in the lower half of the vertical direction are thinned out of the reference pixels for the color difference component and the reference pixels for the luminance component.
- the reference pixel number I L of the reference pixel number I C and the luminance component of the color difference component is made 6 bract together.
- the reference ratio in the vertical direction is “4: 1” and the reference ratio in the horizontal direction is “1: 1”.
- the chroma format is 4: 2: 2
- FIG. 15B shows an example of reference pixel settings when the PU size is 16 ⁇ 16 pixels and the chroma format is 4: 2: 0.
- the reference pixels of the lower third quarter in the vertical direction are thinned out.
- the reference pixel number I L of the reference pixel number I C and the luminance component of the color difference components are both ten.
- the reference ratio in the vertical direction is “8: 1” and the reference ratio in the horizontal direction is “2: 1”.
- the reference pixel value is often stored in a frame memory or a line memory and accessed in units of horizontal lines. Therefore, if the reference ratio in the vertical direction is lower than the reference ratio in the horizontal direction as in the third scenario, the number of accesses to the memory can be reduced even when the number of reference pixels used is the same. Can do. Thereby, the coefficient calculation process in the coefficient calculation unit 44 can be executed at high speed. Also, as in the third scenario, the reference pixel value in the upper line of the block is preferentially used, so that the reference pixel value can be acquired in a short time through continuous access to the memory.
- FIG. 16 is an explanatory diagram showing an example of the definition of the reference ratio in the fourth scenario.
- the prediction control unit 42 controls the reference ratio so that the reference ratio becomes smaller when the capability of the apparatus related to image encoding and decoding is lower.
- a profile and / or a level can be used as a parameter representing the capability of the apparatus. Profiles and levels are usually specified in the sequence parameter set of the encoded stream.
- the capability of the apparatus is divided into two stages of “high” and “low”.
- the reference ratio is “1: 1” regardless of the capabilities of the apparatus.
- the reference ratio when the capability is “low” is half of the reference ratio when the capability is “high”.
- the reference ratio is “1: 1” if the capability is “high”, while the reference ratio is “2: 1” if the capability is “low”. .
- the reference ratio is “2: 1” if the capability is “high”, while the reference ratio is “4: 1” if the capability is “low”.
- the reference ratio is “4: 1” if the capability is “high”, while the reference ratio is “8: 1” if the capability is “low”.
- FIG. 17A shows an example of reference pixel setting when the PU size is 16 ⁇ 16 pixels, the chroma format is 4: 2: 0, the capability is “high”, and the reference ratio is “2: 1”. ing.
- half of the reference pixels of the color difference component and the reference pixel of the luminance component are thinned out.
- the reference pixel number I L of the reference pixel number I C and the luminance component of the color difference component are both eight.
- FIG. 17B shows an example of reference pixel setting when the PU size is 16 ⁇ 16 pixels, the chroma format is 4: 2: 0, the capability is “low”, and the reference ratio is “4: 1”. Is shown.
- the reference pixel number I L of the reference pixel number I C and the luminance component of the color difference component is made four and together.
- the number of reference pixels is set when it is assumed that a device with a lower capability is used. Can be less. Thereby, it is possible to prevent the processing cost exceeding the processing capability of the apparatus from occurring in the coefficient calculation processing in the LM mode.
- FIG. 18A shows an example of reference pixel settings when the PU size is 2 ⁇ 8 pixels and the chroma format is 4: 2: 0.
- the vertical reference ratio is “1: 1”
- the horizontal reference ratio is “2: 1”. ing.
- FIG. 18B shows an example of reference pixel settings when the PU size is 16 ⁇ 4 pixels and the chroma format is 4: 2: 0.
- the horizontal reference ratio is “1: 1”
- the vertical reference ratio is “4: 1”. ing.
- the reference ratio corresponding to the direction of larger size is dynamically selected and controlled to control the direction with fewer reference pixels. A reduction in the number of reference pixels can be avoided, and a reduction in prediction accuracy can be prevented.
- the control of the reference ratio by the prediction control unit 42 according to these scenarios may be performed according to a mapping between a block size and a reference ratio defined in advance in the standard specification of the image coding method, for example.
- mapping uniformly in advance, there is no need to support a large number of reference pixel setting patterns, and it becomes easy to share circuits or logic in the decoder.
- bit depth of image data used in many applications is 8 bits, while larger bit depths such as 10 bits or 12 bits can be used in image data for some applications. Therefore, when the bit depth exceeds a predetermined number of bits (for example, 8 bits), the coefficient calculation unit 44 reduces the reference pixel value to the predetermined number of bits, and then uses the reduced reference pixel value to perform a prediction function.
- the coefficient ⁇ and the coefficient ⁇ may be calculated. Thereby, it is possible to calculate the coefficient ⁇ and the coefficient ⁇ using a common small-scale circuit or logic regardless of the bit depth.
- the prediction control unit 42 controls the “reference ratio” that is the ratio of the number of reference pixels to the block size.
- a concept substantially equivalent to the reference ratio may be expressed by another term such as “reduction ratio” that means a ratio of reference pixels to be reduced.
- the “reference ratio” or “reduction ratio” is “100% (0%)”, “1”, “2: 1”, “4: 1”, etc. It may be described in a percentage format such as “50% (50%)” or “25% (75%)”, or in a numerical format in the range from 0 to 1.
- the above five scenarios are just examples for explanation.
- two or more scenarios out of the five scenarios described above may be combined.
- the mapping between block size and reference ratio (or reduction ratio) as shown in each scenario may be selected adaptively instead of being predefined.
- information specifying the selected mapping may be transmitted from the encoding side to the decoding side within the parameter set or header region of the encoded stream.
- FIG. 19 is a flowchart illustrating an example of the flow of intra prediction processing at the time of encoding by the intra prediction unit 40 having the configuration illustrated in FIG.
- prediction image data is generated in various prediction modes by the prediction unit 46 for the luminance component of the coding unit to be processed, and the optimal prediction mode and prediction unit arrangement are determined by the mode determination unit 48. It is determined (step S100).
- step S110 the coefficient calculation unit 44 and the prediction unit 46 perform prediction processing in the LM mode for the color difference component.
- the coefficient calculation unit 44 and the prediction unit 46 perform intra prediction processing in the non-LM mode (for example, mode 0 to mode 3 illustrated in FIG. 8) for the color difference component (step S120).
- the processes of step S110 and step S120 can be executed for each prediction unit under the control of the prediction control unit 42.
- the mode determination unit 48 calculates a cost function value for each color difference component prediction mode based on the original image data and the predicted image data (step S130). Then, the mode determination unit 48 determines the optimum prediction mode for the color difference component by comparing the cost function values with each other (step S140).
- FIG. 20 is a flowchart showing an example of a detailed flow of the LM mode prediction process in step S110 of FIG.
- the prediction control unit 42 acquires a reference ratio for each prediction unit according to the size of the prediction unit and other parameters (for example, chroma format, profile, or level) (step S111). .
- the coefficient calculation unit 44 is instructed by the prediction control unit 42 for reference pixels to be referred to in calculation formulas (for example, the above formulas (3) and (4)) for calculating the coefficients of the prediction function. It is set according to the reference ratio (step S112). The number of reference pixels set here can be reduced according to the reference ratio. Also, the luminance component of the reference pixel can be resampled depending on the chroma format.
- the coefficient calculation unit 44 calculates the coefficient ⁇ of the prediction function using the pixel value of the set reference pixel, for example, according to the above equation (3) (step S113). Furthermore, the coefficient calculation unit 44 calculates the coefficient ⁇ of the prediction function using the pixel value of the set reference pixel, for example, according to the above equation (4) (step S114).
- the prediction unit 46 substitutes the value of the corresponding luminance component into a prediction function (for example, the above formula (1)) constructed using the coefficient ⁇ and the coefficient ⁇ , thereby predicting the predicted pixel value of each prediction target pixel. Is calculated (step S115).
- a prediction function for example, the above formula (1)
- FIG. 21 is a block diagram illustrating an example of the configuration of the image decoding device 60 according to an embodiment.
- the image decoding device 60 includes an accumulation buffer 61, a lossless decoding unit 62, an inverse quantization unit 63, an inverse orthogonal transform unit 64, an addition unit 65, a deblock filter 66, a rearrangement buffer 67, a D / A A (Digital to Analogue) conversion unit 68, a frame memory 69, selectors 70 and 71, a motion compensation unit 80, and an intra prediction unit 90 are provided.
- the accumulation buffer 61 temporarily accumulates the encoded stream input via the transmission path using a storage medium.
- the lossless decoding unit 62 decodes the encoded stream input from the accumulation buffer 61 according to the encoding method used at the time of encoding. In addition, the lossless decoding unit 62 decodes information multiplexed in the header area of the encoded stream.
- the information multiplexed in the header region of the encoded stream may include, for example, profiles and levels in the sequence parameter set, information on inter prediction and information on intra prediction in the block header.
- the lossless decoding unit 62 outputs information related to inter prediction to the motion compensation unit 80. Further, the lossless decoding unit 62 outputs information related to intra prediction to the intra prediction unit 90.
- the inverse quantization unit 63 performs inverse quantization on the quantized data decoded by the lossless decoding unit 62.
- the inverse orthogonal transform unit 64 generates prediction error data by performing inverse orthogonal transform on the transform coefficient data input from the inverse quantization unit 63 according to the orthogonal transform method used at the time of encoding. Then, the inverse orthogonal transform unit 64 outputs the generated prediction error data to the addition unit 65.
- the addition unit 65 adds the prediction error data input from the inverse orthogonal transform unit 64 and the prediction image data input from the selector 71 to generate decoded image data. Then, the addition unit 65 outputs the generated decoded image data to the deblock filter 66 and the frame memory 69.
- the deblocking filter 66 removes block distortion by filtering the decoded image data input from the adding unit 65, and outputs the decoded image data after filtering to the rearrangement buffer 67 and the frame memory 69.
- the rearrangement buffer 67 rearranges the images input from the deblock filter 66 to generate a series of time-series image data. Then, the rearrangement buffer 67 outputs the generated image data to the D / A conversion unit 68.
- the D / A converter 68 converts the digital image data input from the rearrangement buffer 67 into an analog image signal. Then, the D / A conversion unit 68 displays an image by outputting an analog image signal to a display (not shown) connected to the image decoding device 60, for example.
- the frame memory 69 stores the decoded image data before filtering input from the adding unit 65 and the decoded image data after filtering input from the deblocking filter 66 using a storage medium.
- the selector 70 switches the output destination of the image data from the frame memory 69 between the motion compensation unit 80 and the intra prediction unit 90 for each block in the image according to the mode information acquired by the lossless decoding unit 62. .
- the selector 70 outputs the decoded image data after filtering supplied from the frame memory 69 to the motion compensation unit 80 as reference image data.
- the selector 70 outputs the decoded image data before filtering supplied from the frame memory 69 to the intra prediction unit 90 as reference image data.
- the selector 71 switches the output source of the predicted image data to be supplied to the addition unit 65 between the motion compensation unit 80 and the intra prediction unit 90 according to the mode information acquired by the lossless decoding unit 62. For example, when the inter prediction mode is designated, the selector 71 supplies the predicted image data output from the motion compensation unit 80 to the adding unit 65. In addition, when the intra prediction mode is designated, the selector 71 supplies the predicted image data output from the intra prediction unit 90 to the adding unit 65.
- the motion compensation unit 80 performs motion compensation processing based on the inter prediction information input from the lossless decoding unit 62 and the reference image data from the frame memory 69 to generate predicted image data. Then, the motion compensation unit 80 outputs the generated predicted image data to the selector 71.
- the intra prediction unit 90 performs intra prediction processing based on the information related to intra prediction input from the lossless decoding unit 62 and the reference image data from the frame memory 69, and generates predicted image data. Then, the intra prediction unit 90 outputs the generated predicted image data to the selector 71. Such intra prediction processing by the intra prediction unit 90 will be described in detail later.
- FIG. 22 is a block diagram illustrating an example of a detailed configuration of the intra prediction unit 90 of the image decoding device 60 illustrated in FIG.
- the intra prediction unit 90 includes a prediction control unit 92, a coefficient calculation unit 94, and a prediction unit 96.
- the prediction control unit 92 controls intra prediction processing in the intra prediction unit 90. For example, the prediction control unit 92 sets one or more prediction units for each coding unit based on prediction mode information included in information related to intra prediction. The prediction control unit 92 first executes the intra prediction process for the luminance component (Y), and then executes the intra prediction process for the color difference components (Cb, Cr). In the intra prediction process for the luminance component, the prediction control unit 92 causes the prediction unit 96 to generate a prediction pixel value of the luminance component of each pixel in the prediction mode specified by the prediction mode information. Similarly, in the intra prediction process for the color difference component, the prediction control unit 92 causes the prediction unit 96 to generate a prediction pixel value of the color difference component of each pixel in the prediction mode specified by the prediction mode information.
- the prediction mode candidates for the color difference components include the LM mode described above.
- the prediction control unit 92 variably controls the ratio of the number of reference pixels to the block size, that is, the reference ratio, when calculating the coefficient of the prediction function in the LM mode.
- the control of the reference ratio by the prediction control unit 92 can typically be performed according to the block size. For example, when the block size exceeds a predetermined size, the prediction control unit 92 may control the reference ratio so that the number of reference pixels when calculating the coefficient of the prediction function is constant.
- the mapping between the block size and the reference ratio may be defined in advance and stored in the storage medium of the image decoding device 60, or may be dynamically specified in the header area of the encoded stream.
- the prediction control unit 92 may control the reference ratio according to the chroma format. Further, the prediction control unit 92 may control the reference ratio in accordance with a profile or level that defines the capability of the apparatus. The control of the reference ratio by the prediction control unit 92 may be performed according to any one of the five scenarios described above, any combination thereof, or other scenarios.
- the coefficient calculation unit 94 refers to the prediction function coefficient used by the prediction unit 96 when the LM mode is specified for the color difference component, with reference to the pixels around the prediction unit to which the prediction target pixel belongs, that is, the reference pixel. calculate.
- the prediction function used by the prediction unit 96 is typically a linear function of luminance component values, and is represented by, for example, the above equation (1).
- the number of reference pixels referred to by the coefficient calculation unit 94 when calculating the coefficient of the prediction function is controlled by the prediction control unit 92 as described above. If the reference ratio is not “1: 1”, the coefficient calculation unit 94 calculates the coefficient of the prediction function using only the remaining reference pixels after thinning out the reference pixels according to the reference ratio, for example. obtain.
- the coefficient calculation unit 94 may calculate the coefficient of the prediction function using a common circuit or logic for a plurality of block sizes exceeding a predetermined size. In addition, when the bit depth of the pixel value exceeds a predetermined number of bits, the coefficient calculation unit 94 reduces the reference pixel value to the predetermined number of bits and then uses the reduced reference pixel value to calculate the coefficient of the prediction function. May be calculated.
- the prediction unit 96 uses the reference image data from the frame memory 69 to determine the pixel value of the luminance component and the pixel value of the color difference component of the prediction target pixel under the control of the prediction control unit 92 according to the designated prediction mode. Generate.
- the prediction mode candidates used for the color difference component by the prediction unit 96 may include the LM mode described above.
- the predicting unit 96 applies the luminance component corresponding to the prediction function constructed by using the coefficient ⁇ and the coefficient ⁇ calculated by the coefficient calculating unit 94 (resampling as necessary).
- the predicted pixel value of the color difference component is generated by substituting the value.
- the prediction unit 96 outputs predicted image data generated as a result of prediction to the addition unit 65 via the selector 71.
- FIG. 23 is a flowchart illustrating an example of the flow of intra prediction processing at the time of decoding by the intra prediction unit 90 having the configuration illustrated in FIG.
- the prediction control unit 92 sets one or more prediction units for each coding unit (step S200).
- the subsequent steps S210 to S260 can be executed for each prediction unit under the control of the prediction control unit.
- the prediction control unit 92 recognizes the prediction mode of the luminance component specified by the prediction mode information (step S210). Then, the prediction unit 96 generates a prediction pixel value of the luminance component of each pixel in the prediction unit using the reference image data from the frame memory 69 according to the designated prediction mode (step S220).
- the prediction control unit 92 recognizes the prediction mode of the color difference component specified by the prediction mode information (step S230). And the prediction control part 92 determines whether LM mode is designated (step S240). Here, when the LM mode is designated, the prediction control unit 92 causes the coefficient calculation unit 94 and the prediction unit 96 to perform prediction processing in the LM mode for the color difference component (step S250). The LM mode prediction process in step S250 may be the same as the LM mode prediction process described with reference to FIG. On the other hand, when the LM mode is not designated, the prediction control unit 92 causes the prediction unit 96 to execute intra prediction processing in the non-LM mode for the color difference component (step S260).
- the prediction unit 46 of the intra prediction unit 40 of the image encoding device 10 calculates the prediction pixel value for the color difference component in the LM mode according to the above equation (1).
- the prediction unit 96 of the intra prediction unit 90 of the image decoding device 60 also calculates the predicted pixel value for the color difference component in the LM mode according to the above equation (1).
- Re L ′ (x, y) on the right side of Equation (1) represents the value of the pixel position (x, y) after resampling of the luminance component of the decoded image. Therefore, when the calculation of the predicted pixel value is performed in units of blocks, the pixel value after the resampling of the luminance component is held in units of blocks until the calculation of the predicted pixel values for the color difference components is performed. .
- LCU 1 shown on the left in FIG. 24 is divided into 10 coding units CU 0 to CU 9 .
- the size of LCU 1 is 128 ⁇ 128 pixels
- the size of coding units CU 0 and CU 5 is 64 ⁇ 64 pixels
- the size of coding units CU 1 to CU 4 and CU 6 to CU 9 is 32 ⁇ 32 pixels. It is.
- the prediction pixel value is calculated for each coding unit. In this case, if the chroma format is 4: 2: 0, the pixel value after resampling of the luminance component is held.
- a 32 ⁇ 32 pixel memory may be provided.
- the size of LCU 2 shown on the right of FIG. 24 is 128 ⁇ 128 pixels, and only one CU 10 is included in LCU 2 .
- the chroma format is 4: 2: 0, a 64 ⁇ 64 pixel memory can be prepared in order to hold the pixel value after the re-sampling of the luminance component. The greater the bit depth of the pixel, the more memory resources are consumed.
- the prediction unit 46 of the image encoding device 10 and the prediction unit 96 of the image decoding device 60 thin out the luminance components corresponding to the respective color difference components at a certain thinning rate.
- the luminance component corresponding to each color difference component corresponds to each luminance component after resampling according to the above equation (2), for example.
- the prediction unit 46 and the prediction unit 96 generate a predicted value of each color difference component corresponding to the thinned luminance component using the luminance component value that has not been thinned.
- FIG. 25 is an explanatory diagram for explaining an example of the thinning process according to the present modification.
- an 8 ⁇ 8 pixel prediction unit PU
- the chroma format is 4: 2: 0
- the thinning rate is 25%.
- the thinning rate indicates a ratio of the number of pixels after thinning to the number of pixels before thinning.
- the number of color difference components included in one PU is 4 ⁇ 4.
- the number of luminance components corresponding to each color difference component is also 4 ⁇ 4 by resampling.
- the number of luminance components used for prediction of color difference components in the LM mode is 2 ⁇ 2. More specifically, in the lower right example of FIG. 25, the luminance components Lu2, Lu3 and Lu4 other than the luminance component Lu1 are thinned out of the four luminance components Lu1 to Lu4. Similarly, of the four luminance components Lu5 to Lu8, luminance components Lu6, Lu7 and Lu8 other than the luminance component Lu5 are thinned out.
- the color difference component Cu1 in the lower left of FIG. 25 corresponds to the luminance component Lu1 that has not been thinned out.
- the prediction unit 46 and the prediction unit 96 can generate a predicted value of the color difference component Cu1 by substituting the value of the luminance component Lu1 into the right side of the above equation (1).
- the color difference component Cu2 corresponds to the thinned luminance component Lu2.
- the prediction unit 46 and the prediction unit 96 generate the predicted value of the color difference component Cu2 using the value of any luminance component that has not been thinned out.
- the predicted value of the color difference component Cu2 may be a duplicate of the predicted value of the color difference component Cu1, or may be a value that is linearly interpolated from the two predicted values of the color difference components Cu1 and Cu5.
- the predicted pixel value Pr C (x, y) of the color difference component when the thinning-out rate is 25% is calculated according to the method represented by the following formula (5) or formula (6).
- Expression (5) expresses a copy of a predicted value from an adjacent pixel.
- Equation (6) expresses linear interpolation of predicted values.
- the thinning rate described above affects the amount of memory resources for holding the pixel value after resampling of the luminance component. As the number of luminance components to be thinned out increases, the consumption of memory resources decreases. However, if the number of luminance components to be thinned out is large, there is a possibility that the accuracy of predicting the color difference component is lowered. Therefore, a parameter for designating the thinning rate may be designated in the header of the encoded stream (for example, a sequence parameter set, a picture parameter set, or a slice header). In this case, the prediction unit 96 of the image decoding device 60 determines the thinning rate based on the parameter acquired from the header. Accordingly, it is possible to flexibly change the thinning rate according to the requirements for each device (for example, which of memory resource saving and encoding efficiency is given priority).
- the thinning rate is 50%. In these examples, half of the luminance components after resampling are thinned out. However, even if the thinning rate is the same, the patterns of the luminance component positions to be thinned out (hereinafter referred to as thinning patterns) are different from each other.
- the luminance components Lu2 and Lu4 are thinned out of the four luminance components Lu1 to Lu4.
- the luminance components Lu6 and Lu8 are thinned out of the four luminance components Lu5 to Lu8.
- the predicted value of the color difference component Cu2 corresponding to the thinned luminance component Lu2 may be a duplicate of the predicted value of the color difference component Cu1, or two predicted values of the color difference components Cu1 and Cu5. The linearly interpolated value may be used.
- the thinning pattern in FIG. 26A the luminance components to be thinned out are uniformly dispersed in the PU. Therefore, the thinning pattern in FIG. 26A can realize higher prediction accuracy than other thinning patterns having the same thinning rate.
- the luminance component is thinned out every other line in line units.
- a thinning pattern is advantageous in that, for example, in a device in which pixel values are held by a line memory, more luminance component values can be accessed by one memory access.
- the luminance component is thinned out every other column in units of columns.
- Such a thinning pattern is advantageous in that, for example, when the chroma format is 4: 2: 2 and the number of pixels in the vertical direction is larger, more frequency components in the column direction can be maintained.
- the parameter for designating any one of the plurality of thinning pattern candidates may be designated in the header of the encoded stream.
- the prediction unit 96 of the image decoding device 60 determines the position of the luminance component to be thinned out based on the parameter acquired from the header. Thereby, the thinning pattern can be flexibly changed according to the requirements of each device.
- the prediction unit 46 and the prediction unit 96 may determine a thinning rate according to the reference ratio described above. For example, if the number of reference pixels referenced when calculating the coefficient of the prediction function is smaller, more luminance components can be thinned out. At that time, the prediction unit 46 and the prediction unit 96 may thin out the luminance component at the position corresponding to the thinning position of the reference pixel.
- FIGS. 27A and 27B show examples of correspondence between the thinning position of the reference pixel and the thinning position of the luminance component, respectively.
- the PU size is 16 ⁇ 16 pixels
- the chroma format is 4: 2: 0, and the reference ratio is 2: 1.
- the thinning rate is determined to be 25%, and a thinning pattern similar to the example of FIG. 25 can be selected.
- the PU size is 16 ⁇ 16 pixels
- the chroma format is 4: 2: 0, the vertical reference ratio is 2: 1, and the horizontal reference ratio is 1: 1.
- the thinning rate is determined to be 50%, and a thinning pattern similar to the example of FIG. 26B can be selected.
- all the luminance components of the prediction target block are thinned out for the row where the reference pixel is thinned. All the luminance components of the prediction target block are also thinned out for the columns where the reference pixels are thinned out. Since the determination of the thinning position is simplified by determining the thinning position in this way, it is possible to more easily implement the thinning process according to the present modification. Also in the example of FIG. 27B, all the luminance components of the prediction target block are thinned out for the row where the reference pixel is thinned out.
- FIG. 28 is an explanatory diagram for explaining the order of new processing employed in the present modification.
- an LCU including coding units CU 0 , CU 1 , CU 2 and other coding units is illustrated as an example.
- the coding unit CU 0 is divided into four prediction units PU 00 , PU 01 , PU 02 and PU 03 .
- the coding unit CU 1 is divided into four prediction units PU 10 , PU 11 , PU 12 and PU 13 .
- the coding unit CU 2 is divided into four prediction units PU 20 , PU 21 , PU 22 and PU 23 .
- Y NN intra prediction, Cb NN and Cr NN of the luminance component of the prediction unit PU NN represent each intra prediction of color difference component of the prediction unit PU NN. That is, in the existing method, intra prediction processing is performed for each component for each coding unit. This order of processing is herein referred to as “component order”.
- the prediction control unit 42 of the intra prediction unit 40 of the image encoding device 10 and the prediction control unit 92 of the intra prediction unit 90 of the image decoding device 60 each of the encoding units for each prediction unit.
- the processing of each unit is controlled so that intra prediction processing is performed.
- Such a new processing order is referred to herein as a “PU-specific order”.
- PU-specific order For example, when the PU order is applied to the LCU of FIG. 28, first, intra prediction processing of the luminance component Y 00 and the two color difference components Cb 00 and Cr 00 for the prediction unit PU 00 is performed. Next, intra prediction processing of the luminance component Y 01 and the two color difference components Cb 01 and Cr 01 for the prediction unit PU 01 is performed. Thereafter, the intra prediction process of the three components is repeated in the order of the prediction units PU 02 , PU 03 , PU 10 .
- the amount of memory resources for holding the value of the luminance component referenced in the intra prediction in the LM mode depends on the size of the maximum coding unit. For example, if the maximum coding unit size is 128 ⁇ 128 pixels, the chroma format is 4: 2: 0, and the bit depth is 10 bits, 64 ⁇ 64 ⁇ 10 bits of memory resources are required.
- the amount of memory resources for holding the value of the luminance component referenced in the intra prediction in the LM mode depends on the size of the largest prediction unit.
- the amount of memory resources required for the order by PU is one-fourth of the amount of memory resources required for the order by component. That's it. Therefore, the consumption amount of memory resources can be reduced by adopting the above-described order by PU.
- the image encoding device 10 and the image decoding device 60 include a transmitter or a receiver in satellite broadcasting, cable broadcasting such as cable TV, distribution on the Internet, and distribution to terminals by cellular communication,
- the present invention can be applied to various electronic devices such as a recording apparatus that records an image on a medium such as an optical disk, a magnetic disk, and a flash memory, or a reproducing apparatus that reproduces an image from the storage medium.
- a recording apparatus that records an image on a medium such as an optical disk, a magnetic disk, and a flash memory
- a reproducing apparatus that reproduces an image from the storage medium.
- FIG. 29 shows an example of a schematic configuration of a television apparatus to which the above-described embodiment is applied.
- the television apparatus 900 includes an antenna 901, a tuner 902, a demultiplexer 903, a decoder 904, a video signal processing unit 905, a display unit 906, an audio signal processing unit 907, a speaker 908, an external interface 909, a control unit 910, a user interface 911, And a bus 912.
- Tuner 902 extracts a signal of a desired channel from a broadcast signal received via antenna 901, and demodulates the extracted signal. Then, the tuner 902 outputs the encoded bit stream obtained by the demodulation to the demultiplexer 903. In other words, the tuner 902 serves as a transmission unit in the television apparatus 900 that receives an encoded stream in which an image is encoded.
- the demultiplexer 903 separates the video stream and audio stream of the viewing target program from the encoded bit stream, and outputs each separated stream to the decoder 904. In addition, the demultiplexer 903 extracts auxiliary data such as EPG (Electronic Program Guide) from the encoded bit stream, and supplies the extracted data to the control unit 910. Note that the demultiplexer 903 may perform descrambling when the encoded bit stream is scrambled.
- EPG Electronic Program Guide
- the decoder 904 decodes the video stream and audio stream input from the demultiplexer 903. Then, the decoder 904 outputs the video data generated by the decoding process to the video signal processing unit 905. In addition, the decoder 904 outputs audio data generated by the decoding process to the audio signal processing unit 907.
- the video signal processing unit 905 reproduces the video data input from the decoder 904 and causes the display unit 906 to display the video.
- the video signal processing unit 905 may cause the display unit 906 to display an application screen supplied via a network.
- the video signal processing unit 905 may perform additional processing such as noise removal on the video data according to the setting.
- the video signal processing unit 905 may generate a GUI (Graphical User Interface) image such as a menu, a button, or a cursor, and superimpose the generated image on the output image.
- GUI Graphic User Interface
- the display unit 906 is driven by a drive signal supplied from the video signal processing unit 905, and displays a video or an image on a video screen of a display device (for example, a liquid crystal display, a plasma display, or an OLED).
- a display device for example, a liquid crystal display, a plasma display, or an OLED.
- the audio signal processing unit 907 performs reproduction processing such as D / A conversion and amplification on the audio data input from the decoder 904, and outputs audio from the speaker 908.
- the audio signal processing unit 907 may perform additional processing such as noise removal on the audio data.
- the external interface 909 is an interface for connecting the television apparatus 900 to an external device or a network.
- a video stream or an audio stream received via the external interface 909 may be decoded by the decoder 904. That is, the external interface 909 also has a role as a transmission unit in the television apparatus 900 that receives an encoded stream in which an image is encoded.
- the control unit 910 has a processor such as a CPU (Central Processing Unit) and a memory such as a RAM (Random Access Memory) and a ROM (Read Only Memory).
- the memory stores a program executed by the CPU, program data, EPG data, data acquired via a network, and the like.
- the program stored in the memory is read and executed by the CPU when the television device 900 is activated, for example.
- the CPU controls the operation of the television device 900 according to an operation signal input from the user interface 911, for example, by executing the program.
- the user interface 911 is connected to the control unit 910.
- the user interface 911 includes, for example, buttons and switches for the user to operate the television device 900, a remote control signal receiving unit, and the like.
- the user interface 911 detects an operation by the user via these components, generates an operation signal, and outputs the generated operation signal to the control unit 910.
- the bus 912 connects the tuner 902, the demultiplexer 903, the decoder 904, the video signal processing unit 905, the audio signal processing unit 907, the external interface 909, and the control unit 910 to each other.
- the decoder 904 has the function of the image decoding apparatus 60 according to the above-described embodiment.
- the LM mode is adopted when decoding an image on the television device 900, an increase in processing cost accompanying an increase in the block size can be suppressed.
- FIG. 30 shows an example of a schematic configuration of a mobile phone to which the above-described embodiment is applied.
- a mobile phone 920 includes an antenna 921, a communication unit 922, an audio codec 923, a speaker 924, a microphone 925, a camera unit 926, an image processing unit 927, a demultiplexing unit 928, a recording / reproducing unit 929, a display unit 930, a control unit 931, an operation A portion 932 and a bus 933.
- the antenna 921 is connected to the communication unit 922.
- the speaker 924 and the microphone 925 are connected to the audio codec 923.
- the operation unit 932 is connected to the control unit 931.
- the bus 933 connects the communication unit 922, the audio codec 923, the camera unit 926, the image processing unit 927, the demultiplexing unit 928, the recording / reproducing unit 929, the display unit 930, and the control unit 931 to each other.
- the mobile phone 920 has various operation modes including a voice call mode, a data communication mode, a shooting mode, and a videophone mode, and is used for sending and receiving voice signals, sending and receiving e-mail or image data, taking images, and recording data. Perform the action.
- the analog voice signal generated by the microphone 925 is supplied to the voice codec 923.
- the audio codec 923 converts an analog audio signal into audio data, A / D converts the compressed audio data, and compresses it. Then, the audio codec 923 outputs the compressed audio data to the communication unit 922.
- the communication unit 922 encodes and modulates the audio data and generates a transmission signal. Then, the communication unit 922 transmits the generated transmission signal to a base station (not shown) via the antenna 921. In addition, the communication unit 922 amplifies a radio signal received via the antenna 921 and performs frequency conversion to acquire a received signal.
- the communication unit 922 demodulates and decodes the received signal to generate audio data, and outputs the generated audio data to the audio codec 923.
- the audio codec 923 expands the audio data and performs D / A conversion to generate an analog audio signal. Then, the audio codec 923 supplies the generated audio signal to the speaker 924 to output audio.
- the control unit 931 generates character data constituting the e-mail in response to an operation by the user via the operation unit 932.
- the control unit 931 causes the display unit 930 to display characters.
- the control unit 931 generates e-mail data in response to a transmission instruction from the user via the operation unit 932, and outputs the generated e-mail data to the communication unit 922.
- the communication unit 922 encodes and modulates email data and generates a transmission signal. Then, the communication unit 922 transmits the generated transmission signal to a base station (not shown) via the antenna 921.
- the communication unit 922 amplifies a radio signal received via the antenna 921 and performs frequency conversion to acquire a received signal.
- the communication unit 922 demodulates and decodes the received signal to restore the email data, and outputs the restored email data to the control unit 931.
- the control unit 931 displays the content of the electronic mail on the display unit 930 and stores the electronic mail data in the storage medium of the recording / reproducing unit 929.
- the recording / reproducing unit 929 has an arbitrary readable / writable storage medium.
- the storage medium may be a built-in storage medium such as a RAM or a flash memory, or an externally mounted storage medium such as a hard disk, a magnetic disk, a magneto-optical disk, an optical disk, a USB memory, or a memory card. May be.
- the camera unit 926 images a subject to generate image data, and outputs the generated image data to the image processing unit 927.
- the image processing unit 927 encodes the image data input from the camera unit 926 and stores the encoded stream in the storage medium of the recording / playback unit 929.
- the demultiplexing unit 928 multiplexes the video stream encoded by the image processing unit 927 and the audio stream input from the audio codec 923, and the multiplexed stream is the communication unit 922. Output to.
- the communication unit 922 encodes and modulates the stream and generates a transmission signal. Then, the communication unit 922 transmits the generated transmission signal to a base station (not shown) via the antenna 921.
- the communication unit 922 amplifies a radio signal received via the antenna 921 and performs frequency conversion to acquire a received signal.
- These transmission signal and reception signal may include an encoded bit stream.
- the communication unit 922 demodulates and decodes the received signal to restore the stream, and outputs the restored stream to the demultiplexing unit 928.
- the demultiplexing unit 928 separates the video stream and the audio stream from the input stream, and outputs the video stream to the image processing unit 927 and the audio stream to the audio codec 923.
- the image processing unit 927 decodes the video stream and generates video data.
- the video data is supplied to the display unit 930, and a series of images is displayed on the display unit 930.
- the audio codec 923 decompresses the audio stream and performs D / A conversion to generate an analog audio signal. Then, the audio codec 923 supplies the generated audio signal to the speaker 924 to output audio.
- the image processing unit 927 has the functions of the image encoding device 10 and the image decoding device 60 according to the above-described embodiment.
- FIG. 31 shows an example of a schematic configuration of a recording / reproducing apparatus to which the above-described embodiment is applied.
- the recording / reproducing device 940 encodes audio data and video data of a received broadcast program and records the encoded data on a recording medium.
- the recording / reproducing device 940 may encode audio data and video data acquired from another device and record them on a recording medium, for example.
- the recording / reproducing device 940 reproduces data recorded on the recording medium on a monitor and a speaker, for example, in accordance with a user instruction. At this time, the recording / reproducing device 940 decodes the audio data and the video data.
- the recording / reproducing device 940 includes a tuner 941, an external interface 942, an encoder 943, an HDD (Hard Disk Drive) 944, a disk drive 945, a selector 946, a decoder 947, an OSD (On-Screen Display) 948, a control unit 949, and a user interface. 950.
- Tuner 941 extracts a signal of a desired channel from a broadcast signal received via an antenna (not shown), and demodulates the extracted signal. Then, the tuner 941 outputs the encoded bit stream obtained by the demodulation to the selector 946. That is, the tuner 941 has a role as a transmission unit in the recording / reproducing apparatus 940.
- the external interface 942 is an interface for connecting the recording / reproducing apparatus 940 to an external device or a network.
- the external interface 942 may be, for example, an IEEE 1394 interface, a network interface, a USB interface, or a flash memory interface.
- video data and audio data received via the external interface 942 are input to the encoder 943. That is, the external interface 942 serves as a transmission unit in the recording / reproducing device 940.
- the encoder 943 encodes video data and audio data when the video data and audio data input from the external interface 942 are not encoded. Then, the encoder 943 outputs the encoded bit stream to the selector 946.
- the HDD 944 records an encoded bit stream in which content data such as video and audio is compressed, various programs, and other data on an internal hard disk. Also, the HDD 944 reads out these data from the hard disk when playing back video and audio.
- the disk drive 945 performs recording and reading of data to and from the mounted recording medium.
- the recording medium loaded in the disk drive 945 may be, for example, a DVD disk (DVD-Video, DVD-RAM, DVD-R, DVD-RW, DVD + R, DVD + RW, etc.) or a Blu-ray (registered trademark) disk. .
- the selector 946 selects an encoded bit stream input from the tuner 941 or the encoder 943 when recording video and audio, and outputs the selected encoded bit stream to the HDD 944 or the disk drive 945. In addition, the selector 946 outputs the encoded bit stream input from the HDD 944 or the disk drive 945 to the decoder 947 during video and audio reproduction.
- the decoder 947 decodes the encoded bit stream and generates video data and audio data. Then, the decoder 947 outputs the generated video data to the OSD 948. The decoder 904 outputs the generated audio data to an external speaker.
- the OSD 948 reproduces the video data input from the decoder 947 and displays the video. Further, the OSD 948 may superimpose a GUI image such as a menu, a button, or a cursor on the video to be displayed.
- a GUI image such as a menu, a button, or a cursor
- the control unit 949 includes a processor such as a CPU and memories such as a RAM and a ROM.
- the memory stores a program executed by the CPU, program data, and the like.
- the program stored in the memory is read and executed by the CPU when the recording / reproducing apparatus 940 is activated, for example.
- the CPU controls the operation of the recording / reproducing device 940 according to an operation signal input from the user interface 950, for example, by executing the program.
- the user interface 950 is connected to the control unit 949.
- the user interface 950 includes, for example, buttons and switches for the user to operate the recording / reproducing device 940, a remote control signal receiving unit, and the like.
- the user interface 950 detects an operation by the user via these components, generates an operation signal, and outputs the generated operation signal to the control unit 949.
- the encoder 943 has the function of the image encoding apparatus 10 according to the above-described embodiment.
- the decoder 947 has the function of the image decoding device 60 according to the above-described embodiment.
- FIG. 32 shows an example of a schematic configuration of an imaging apparatus to which the above-described embodiment is applied.
- the imaging device 960 images a subject to generate an image, encodes the image data, and records it on a recording medium.
- the imaging device 960 includes an optical block 961, an imaging unit 962, a signal processing unit 963, an image processing unit 964, a display unit 965, an external interface 966, a memory 967, a media drive 968, an OSD 969, a control unit 970, a user interface 971, and a bus. 972.
- the optical block 961 is connected to the imaging unit 962.
- the imaging unit 962 is connected to the signal processing unit 963.
- the display unit 965 is connected to the image processing unit 964.
- the user interface 971 is connected to the control unit 970.
- the bus 972 connects the image processing unit 964, the external interface 966, the memory 967, the media drive 968, the OSD 969, and the control unit 970 to each other.
- the optical block 961 includes a focus lens and a diaphragm mechanism.
- the optical block 961 forms an optical image of the subject on the imaging surface of the imaging unit 962.
- the imaging unit 962 includes an image sensor such as a CCD or a CMOS, and converts an optical image formed on the imaging surface into an image signal as an electrical signal by photoelectric conversion. Then, the imaging unit 962 outputs the image signal to the signal processing unit 963.
- the signal processing unit 963 performs various camera signal processing such as knee correction, gamma correction, and color correction on the image signal input from the imaging unit 962.
- the signal processing unit 963 outputs the image data after the camera signal processing to the image processing unit 964.
- the image processing unit 964 encodes the image data input from the signal processing unit 963 and generates encoded data. Then, the image processing unit 964 outputs the generated encoded data to the external interface 966 or the media drive 968. The image processing unit 964 also decodes encoded data input from the external interface 966 or the media drive 968 to generate image data. Then, the image processing unit 964 outputs the generated image data to the display unit 965. In addition, the image processing unit 964 may display the image by outputting the image data input from the signal processing unit 963 to the display unit 965. Further, the image processing unit 964 may superimpose display data acquired from the OSD 969 on an image output to the display unit 965.
- the OSD 969 generates a GUI image such as a menu, a button, or a cursor, for example, and outputs the generated image to the image processing unit 964.
- the external interface 966 is configured as a USB input / output terminal, for example.
- the external interface 966 connects the imaging device 960 and a printer, for example, when printing an image.
- a drive is connected to the external interface 966 as necessary.
- a removable medium such as a magnetic disk or an optical disk is attached to the drive, and a program read from the removable medium can be installed in the imaging device 960.
- the external interface 966 may be configured as a network interface connected to a network such as a LAN or the Internet. That is, the external interface 966 has a role as a transmission unit in the imaging device 960.
- the recording medium mounted on the media drive 968 may be any readable / writable removable medium such as a magnetic disk, a magneto-optical disk, an optical disk, or a semiconductor memory. Further, a recording medium may be fixedly attached to the media drive 968, and a non-portable storage unit such as an internal hard disk drive or an SSD (Solid State Drive) may be configured.
- a non-portable storage unit such as an internal hard disk drive or an SSD (Solid State Drive) may be configured.
- the control unit 970 includes a processor such as a CPU and memories such as a RAM and a ROM.
- the memory stores a program executed by the CPU, program data, and the like.
- the program stored in the memory is read and executed by the CPU when the imaging device 960 is activated, for example.
- the CPU controls the operation of the imaging device 960 according to an operation signal input from the user interface 971, for example, by executing the program.
- the user interface 971 is connected to the control unit 970.
- the user interface 971 includes, for example, buttons and switches for the user to operate the imaging device 960.
- the user interface 971 detects an operation by the user via these components, generates an operation signal, and outputs the generated operation signal to the control unit 970.
- the image processing unit 964 has the functions of the image encoding device 10 and the image decoding device 60 according to the above-described embodiment. As a result, when the LM mode is employed when encoding and decoding an image with the imaging device 960, an increase in processing cost due to an increase in block size can be suppressed.
- the image encoding device 10 and the image decoding device 60 according to an embodiment have been described with reference to FIGS. 1 to 32.
- the LM mode using a function of the value of the corresponding luminance component is adopted for intra prediction of the color difference component in image encoding and decoding, it is referred to when calculating the coefficient of the function.
- the ratio of the number of reference pixels to the block size is variably controlled. Therefore, an increase in the number of reference pixels accompanying an increase in block size can be suppressed, and an increase in processing cost can be avoided or alleviated.
- the ratio can be controlled so that the number of reference pixels is constant when the block size exceeds a predetermined size.
- the coefficient of the function can be calculated using a common circuit or logic for a plurality of block sizes. Therefore, an increase in circuit scale or logic scale due to the adoption of the LM mode can be suppressed.
- the reference pixels are not excessively reduced when the block size is smaller than the predetermined size. Therefore, it is possible to prevent the prediction accuracy in the LM mode from being lowered due to the shortage of the reference pixels.
- a relatively large block size can be normally set when an image in a block is monotonous and easy to predict. Therefore, even if the number of reference pixels is reduced when the block size is larger, the risk that the accuracy of the prediction is significantly reduced by that is small.
- the ratio can be controlled separately in the vertical direction of the block and the horizontal direction of the block.
- the coefficient of the function can be calculated using a common circuit or logic without depending on the chroma format.
- the reference pixels to be reduced can be adaptively changed according to the shape of the block.
- the method for transmitting such information is not limited to such an example.
- these pieces of information may be transmitted or recorded as separate data associated with the encoded bitstream without being multiplexed into the encoded bitstream.
- the term “associate” means that an image (which may be a part of an image such as a slice or a block) included in the bitstream and information corresponding to the image can be linked at the time of decoding. Means. That is, information may be transmitted on a transmission path different from that of the image (or bit stream).
- the information may be recorded on a recording medium (or another recording area of the same recording medium) different from the image (or bit stream). Furthermore, the information and the image (or the bit stream) may be associated with each other in an arbitrary unit such as a plurality of frames, one frame, or a part of the frame.
- a prediction unit that generates a prediction value of a color difference component of a pixel of an image to be decoded using a function of a value of a corresponding luminance component;
- a coefficient calculation unit that calculates the coefficient of the function used by the prediction unit with reference to pixels around the block to which the pixel belongs;
- a control unit that controls the ratio of the number of reference pixels used by the coefficient calculation unit to the block size of the block;
- An image processing apparatus comprising: (2) The image processing apparatus according to (1), wherein the control unit controls the ratio according to the block size.
- the control unit controls the ratio when the block size is the first size to be smaller than the ratio when the block size is the second size smaller than the first size.
- the image processing apparatus according to (2).
- the control unit controls the ratio so that the number of reference pixels is constant when the block size exceeds a predetermined size.
- the coefficient calculation unit calculates the coefficient using a common circuit or logic for a plurality of block sizes exceeding the predetermined size.
- the control unit controls the ratio according to a predefined mapping between a block size and the ratio.
- the control unit controls the ratio by changing a number of reference pixels to be thinned out when calculating the coefficient. .
- the said control part is an image processing apparatus as described in said (7) which makes zero the number of the reference pixels thinned out when the said block size is less than predetermined size.
- the control unit includes a first ratio that is a ratio of the number of reference pixels on the left side of the block to a vertical size of the block, and a ratio of the number of reference pixels on the block to the horizontal size of the block.
- the image processing apparatus according to (9), wherein the control unit controls the first ratio or the second ratio so that the first ratio is equal to or less than the second ratio for the same block size. .
- the control unit controls only the ratio corresponding to the larger direction of the first ratio and the second ratio, according to (9).
- Image processing apparatus When the chroma format representing the resolution of the color difference component is 4: 2: 2, the control unit is configured to make the number of reference pixels on the left of the block equal to the number of reference pixels on the block.
- the control unit is configured to reduce the ratio when the chroma format represents the first resolution to be smaller than the ratio when the chroma format represents the second resolution lower than the first resolution.
- the coefficient calculation unit calculates the coefficient using the pixel value of the reference pixel reduced to the predetermined number of bits when the bit depth of the pixel value exceeds a predetermined number of bits. Image processing apparatus.
- An image processing method including: (17) A prediction unit that generates a prediction value of a color difference component of a pixel of an image to be encoded using a function of a value of a corresponding luminance component; A coefficient calculation unit that calculates the coefficient of the function used by the prediction unit with reference to pixels around the block to which the pixel belongs; A control unit that controls the ratio of the number of reference pixels used by the coefficient calculation unit to the block size of the block; An image processing apparatus comprising: (18) Generating a predicted value of the color difference component of the pixel of the image to be encoded using a function of the value of the corresponding luminance component; Calculating the coefficient of the function with reference to pixels
- Image encoding device (image processing device) 42 Prediction control unit 44 Coefficient calculation unit (decimation unit) 46 Prediction unit 60 Image decoding device (image processing device) 92 Prediction control unit 94 Coefficient calculation unit (thinning unit) 96 Predictor
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Abstract
Description
1.一実施形態に係る画像符号化装置の構成例
2.一実施形態に係る符号化時の処理の流れ
3.一実施形態に係る画像復号装置の構成例
4.一実施形態に係る復号時の処理の流れ
5.変形例
6.応用例
7.まとめ
[1-1.全体的な構成例]
図1は、一実施形態に係る画像符号化装置10の構成の一例を示すブロック図である。図1を参照すると、画像符号化装置10は、A/D(Analogue to Digital)変換部11、並べ替えバッファ12、減算部13、直交変換部14、量子化部15、可逆符号化部16、蓄積バッファ17、レート制御部18、逆量子化部21、逆直交変換部22、加算部23、デブロックフィルタ24、フレームメモリ25、セレクタ26及び27、動き探索部30、並びにイントラ予測部40を備える。
図2は、図1に示した画像符号化装置10のイントラ予測部40の詳細な構成の一例を示すブロック図である。図2を参照すると、イントラ予測部40は、予測制御部42、係数算出部44、予測部46及びモード判定部48を有する。
次に、イントラ予測部40の予測部46により使用され得る予測モードの候補について説明する。
輝度成分についての予測モードの候補は、H.264/AVCなどの既存の画像符号化方式において採用されている予測モードであってよい。図3~図5は、予測単位のサイズが4×4画素である場合のそうした予測モードの候補について説明するための説明図である。
a=e=i=m=Ra
b=f=j=n=Rb
c=g=k=o=Rc
d=h=l=p=Rd
a=b=c=d=Ri
e=f=g=h=Rj
i=j=k=l=Rk
m=n=o=p=Rl
a=b=…=p=(Ra+Rb+Rc+Rd+Ri+Rj+Rk+Rl+4)>>3
a=b=…=p=(Ra+Rb+Rc+Rd+2)>>2
a=b=…=p=(Ri+Rj+Rk+Rl+2)>>2
a=b=…=p=128
a=(Ra+2Rb+Rc+2)>>2
b=e=(Rb+2Rc+Rd+2)>>2
c=f=i=(Rc+2Rd+Re+2)>>2
d=g=j=m=(Rd+2Re+Rf+2)>>2
h=k=n=(Re+2Rf+Rg+2)>>2
l=o=(Rf+2Rg+Rh+2)>>2
p=(Rg+3Rh+2)>>2
m=(Rj+2Rk+Rl+2)>>2
i=n=(Ri+2Rj+Rk+2)>>2
e=j=o=(Rm+2Ri+Rj+2)>>2
a=f=k=p=(Ra+2Rm+Ri+2)>>2
b=g=l=(Rm+2Ra+Rb+2)>>2
c=h=(Ra+2Rb+Rc+2)>>2
d=(Rb+2Rc+Rd+2)>>2
a=j=(Rm+Ra+1)>>1
b=k=(Ra+Rb+1)>>1
c=l=(Rb+Rc+1)>>1
d=(Rc+Rd+1)>>1
e=n=(Ri+2Rm+Ra+2)>>2
f=o=(Rm+2Ra+Rb+2)>>2
g=p=(Ra+2Rb+Rc+2)>>2
h=(Rb+2Rc+Rd+2)>>2
i=(Rm+2Ri+Rj+2)>>2
m=(Ri+2Rj+Rk+2)>>2
a=g=(Rm+Ri+1)>>1
b=h=(Ri+2Rm+Ra+2)>>2
c=(Rm+2Ra+Rb+2)>>2
d=(Ra+2Rb+Rc+2)>>2
e=k=(Ri+Rj+1)>>1
f=l=(Rm+2Ri+Rj+2)>>2
i=o=(Rj+Rk+1)>>1
j=p=(Ri+2Rj+Rk+2)>>2
m=(Rk+Rl+1)>>1
n=(Rj+2Rk+Rl+2)>>2
a=(Ra+Rb+1)>>1
b=i=(Rb+Rc+1)>>1
c=j=(Rc+Rd+1)>>1
d=k=(Rd+Re+1)>>1
l=(Re+Rf+1)>>1
e=(Ra+2Rb+Rc+2)>>2
f=m=(Rb+2Rc+Rd+2)>>2
g=n=(Rc+2Rd+Re+2)>>2
h=o=(Rd+2Re+Rf+2)>>2
p=(Re+2Rf+Rg+2)>>2
a=(Ri+Rj+1)>>1
b=(Ri+2Rj+Rk+2)>>2
c=e=(Rj+Rk+1)>>1
d=f=(Rj+2Rk+Rl+2)>>2
g=i=(Rk+Rl+1)>>1
h=j=(Rk+3Rl+2)>>2
k=l=m=n=o=p=Rl
色差成分についての予測モードは、輝度成分についての予測モードとは独立して選択され得る。図8には、色差成分のブロックサイズが8×8画素である場合に使用され得る予測モードの候補のうち、H.264/AVCなどの既存の画像符号化方式において採用されている4つの予測モード(モード0~モード3)が示されている。
LMモードでは、色差成分についての予測画素値は、対応する輝度成分の値の線型関数を用いて計算される。例えば、LMモードにおいて使用される予測関数は、上記非特許文献2に記載されている次のような線型一次関数であってよい:
典型的には、予測制御部42は、ブロックサイズに対する参照画素数の比率である参照比を、ブロックサイズがより大きいほどより小さくなるように制御する。それにより、ブロックサイズが拡大する場合の処理コストの増加が抑制される。予測制御部42は、処理コストが問題とならない程度にブロックサイズが小さい場合には、ブロックサイズが異なっても参照比を変化させなくてもよい。以下、図10~図18Bを用いて、参照比の制御の例示的な5つのシナリオについて説明する。
図10は、第1のシナリオにおける参照比の定義の一例を示す説明図である。
図12は、第2のシナリオにおける参照比の定義の一例を示す説明図である。第2のシナリオでは、予測制御部42は、予測単位のサイズに加えてクロマフォーマットに応じて、参照比を制御する。また、予測制御部42は、垂直方向のサイズに対する左の参照画素数の比率である第1の参照比と、水平方向のサイズに対する上の参照画素数の比率である第2の参照比とを別々に制御する。
図14は、第3のシナリオにおける参照比の定義の一例を示す説明図である。第3のシナリオにおいても、予測制御部42は、垂直方向のサイズに対する左の参照画素数の比率である第1の参照比と、水平方向のサイズに対する上の参照画素数の比率である第2の参照比とを別々に制御する。また、第3のシナリオでは、予測制御部42は、同じブロックサイズについて垂直方向の参照比が水平方向の参照比以下となるように、これら参照比を制御する。
図16は、第4のシナリオにおける参照比の定義の一例を示す説明図である。第4のシナリオにおいて、予測制御部42は、画像の符号化及び復号に関する装置のケイパビリティがより低い場合に参照比がより小さくなるように、参照比を制御する。HEVCでは、装置のケイパビリティを表すパラメータとして、例えばプロファイル若しくはレベル又はその双方を用いることができる。プロファイル及びレベルは、通常、符号化ストリームのシーケンスパラメータセット内で指定される。
Xiaoran Cao Tsinghuaらは、“CE6.b1 Report on Short Distance Intra Prediction Method”(JCTVC-E278,2011年3月)において、サイズの小さい非正方形の予測単位を使用して符号化効率を向上させる、短距離イントラ予測法(Short Distance Intra Prediction Method)を提案している。短距離イントラ予測法では、例えば1×4画素、2×8画素、4×16画素、4×1画素、8×2画素、16×4画素などの様々なサイズの予測単位が画像内に設定され得る。この場合、予測単位の垂直方向のサイズ及び水平方向のサイズのうちいずれのサイズがより大きいかは、予測単位の設定に依存する。そこで、第5のシナリオでは、予測制御部42は、短距離イントラ予測法が用いられる場合に、垂直方向の参照比及び水平方向の参照比のうちサイズのより大きい方向に対応する参照比を動的に選択し、選択した参照比を制御する。
次に、図19及び図20を用いて、符号化時の処理の流れを説明する。図19は、図2に例示した構成を有するイントラ予測部40による符号化時のイントラ予測処理の流れの一例を示すフローチャートである。
本節では、図21及び図22を用いて、一実施形態に係る画像復号装置の構成例について説明する。
図21は、一実施形態に係る画像復号装置60の構成の一例を示すブロック図である。図21を参照すると、画像復号装置60は、蓄積バッファ61、可逆復号部62、逆量子化部63、逆直交変換部64、加算部65、デブロックフィルタ66、並べ替えバッファ67、D/A(Digital to Analogue)変換部68、フレームメモリ69、セレクタ70及び71、動き補償部80、並びにイントラ予測部90を備える。
図22は、図21に示した画像復号装置60のイントラ予測部90の詳細な構成の一例を示すブロック図である。図22を参照すると、イントラ予測部90は、予測制御部92、係数算出部94及び予測部96を有する。
次に、図23を用いて、復号時の処理の流れを説明する。図23は、図22に例示した構成を有するイントラ予測部90による復号時のイントラ予測処理の流れの一例を示すフローチャートである。
上述した実施形態において、画像符号化装置10のイントラ予測部40の予測部46は、LMモードでの色差成分についての予測画素値を、上記式(1)に従って計算する。同様に、画像復号装置60のイントラ予測部90の予測部96もまた、LMモードでの色差成分についての予測画素値を、上記式(1)に従って計算する。式(1)の右辺のReL´(x,y)は、復号画像の輝度成分のリサンプリング後の画素位置(x,y)の値を表す。従って、予測画素値の計算がブロック単位で行われる場合には、色差成分についての予測画素値の計算が行われるまで、ブロック単位で輝度成分のリサンプリング後の画素値が保持されることになる。
第1の変形例において、画像符号化装置10の予測部46及び画像復号装置60の予測部96は、各色差成分に対応する輝度成分をある間引き率で間引く。各色差成分に対応する輝度成分とは、例えば上記式(2)に従ったリサンプリングの後の各輝度成分に相当する。そして、予測部46及び予測部96は、間引かれた輝度成分に対応する各色差成分の予測値を、間引かれていない輝度成分の値を用いて生成する。
第2の変形例では、画像符号化装置10のイントラ予測部40及び画像復号装置60のイントラ予測部90による新たな処理の順序が採用される。
上述した実施形態に係る画像符号化装置10及び画像復号装置60は、衛星放送、ケーブルTVなどの有線放送、インターネット上での配信、及びセルラー通信による端末への配信などにおける送信機若しくは受信機、光ディスク、磁気ディスク及びフラッシュメモリなどの媒体に画像を記録する記録装置、又は、これら記憶媒体から画像を再生する再生装置などの様々な電子機器に応用され得る。以下、4つの応用例について説明する。
図29は、上述した実施形態を適用したテレビジョン装置の概略的な構成の一例を示している。テレビジョン装置900は、アンテナ901、チューナ902、デマルチプレクサ903、デコーダ904、映像信号処理部905、表示部906、音声信号処理部907、スピーカ908、外部インタフェース909、制御部910、ユーザインタフェース911、及びバス912を備える。
図30は、上述した実施形態を適用した携帯電話機の概略的な構成の一例を示している。携帯電話機920は、アンテナ921、通信部922、音声コーデック923、スピーカ924、マイクロホン925、カメラ部926、画像処理部927、多重分離部928、記録再生部929、表示部930、制御部931、操作部932、及びバス933を備える。
図31は、上述した実施形態を適用した記録再生装置の概略的な構成の一例を示している。記録再生装置940は、例えば、受信した放送番組の音声データ及び映像データを符号化して記録媒体に記録する。また、記録再生装置940は、例えば、他の装置から取得される音声データ及び映像データを符号化して記録媒体に記録してもよい。また、記録再生装置940は、例えば、ユーザの指示に応じて、記録媒体に記録されているデータをモニタ及びスピーカ上で再生する。このとき、記録再生装置940は、音声データ及び映像データを復号する。
図32は、上述した実施形態を適用した撮像装置の概略的な構成の一例を示している。撮像装置960は、被写体を撮像して画像を生成し、画像データを符号化して記録媒体に記録する。
ここまで、図1~図32を用いて、一実施形態に係る画像符号化装置10及び画像復号装置60について説明した。本実施形態によれば、画像の符号化及び復号における色差成分のイントラ予測にあたり、対応する輝度成分の値の関数を用いるLMモードが採用される場合に、関数の係数の算出の際に参照される参照画素の数のブロックサイズに対する比率が、可変的に制御される。従って、ブロックサイズの拡大に伴う参照画素数の増大を抑制して、処理コストの増加を回避し又は緩和することができる。
(1)
復号される画像の画素の色差成分の予測値を、対応する輝度成分の値の関数を用いて生成する予測部と、
前記予測部により使用される前記関数の係数を、前記画素が属するブロックの周辺の画素を参照して算出する係数算出部と、
前記ブロックのブロックサイズに対する前記係数算出部により使用される参照画素数の比率を制御する制御部と、
を備える画像処理装置。
(2)
前記制御部は、前記ブロックサイズに応じて前記比率を制御する、前記(1)に記載の画像処理装置。
(3)
前記制御部は、前記ブロックサイズが第1のサイズである場合の前記比率を、前記ブロックサイズが前記第1のサイズよりも小さい第2のサイズである場合の前記比率よりも小さくなるように制御する、前記(2)に記載の画像処理装置。
(4)
前記制御部は、前記ブロックサイズが所定のサイズを上回る場合に前記参照画素数が一定となるように、前記比率を制御する、前記(3)に記載の画像処理装置。
(5)
前記係数算出部は、前記所定のサイズを上回る複数のブロックサイズについて共通的な回路又はロジックを用いて前記係数を算出する、前記(4)に記載の画像処理装置。
(6)
前記制御部は、ブロックサイズと前記比率との間の予め定義されるマッピングに従って、前記比率を制御する、前記(1)~(5)のいずれか1項に記載の画像処理装置。
(7)
前記制御部は、前記係数の算出の際に間引かれる参照画素の数を変化させることにより、前記比率を制御する、前記(1)~(6)のいずれか1項に記載の画像処理装置。
(8)
前記制御部は、前記ブロックサイズが所定のサイズを下回る場合には、間引かれる参照画素の数をゼロとする、前記(7)に記載の画像処理装置。
(9)
前記制御部は、前記ブロックの垂直方向のサイズに対する前記ブロックの左の参照画素数の比率である第1の比率と、前記ブロックの水平方向のサイズに対する前記ブロックの上の参照画素数の比率である第2の比率とを別々に制御する、前記(1)に記載の画像処理装置
(10)
前記制御部は、同じブロックサイズについて前記第1の比率が前記第2の比率以下となるように前記第1の比率又は前記第2の比率を制御する、前記(9)に記載の画像処理装置。
(11)
前記制御部は、短距離イントラ予測法が用いられる場合には、前記第1の比率及び前記第2の比率のうちサイズのより大きい方向に対応する比率のみを制御する、前記(9)に記載の画像処理装置。
(12)
前記制御部は、前記色差成分の解像度を表すクロマフォーマットが4:2:2である場合に、前記ブロックの左の参照画素数が前記ブロックの上の参照画素数と等しくなるように、前記第1の比率を制御する、前記(9)に記載の画像処理装置。
(13)
前記制御部は、前記色差成分の解像度を表すクロマフォーマットに応じて前記比率を制御する、前記(1)に記載の画像処理装置。
(14)
前記制御部は、前記クロマフォーマットが第1の解像度を表している場合の前記比率を、前記クロマフォーマットが前記第1の解像度よりも低い第2の解像度を表している場合の前記比率よりも小さくなるように制御する、前記(13)に記載の画像処理装置。
(15)
前記係数算出部は、画素値のビット深度が所定のビット数を上回る場合に、前記所定のビット数に削減された参照画素の画素値を用いて前記係数を算出する、前記(5)に記載の画像処理装置。
(16)
復号される画像の画素の色差成分の予測値を、対応する輝度成分の値の関数を用いて生成することと、
前記関数の係数を、前記画素が属するブロックの周辺の画素を参照して算出することと、
前記係数の算出の際に使用される参照画素数の前記ブロックのブロックサイズに対する比率を制御することと、
を含む画像処理方法。
(17)
符号化される画像の画素の色差成分の予測値を、対応する輝度成分の値の関数を用いて生成する予測部と、
前記予測部により使用される前記関数の係数を、前記画素が属するブロックの周辺の画素を参照して算出する係数算出部と、
前記ブロックのブロックサイズに対する前記係数算出部により使用される参照画素数の比率を制御する制御部と、
を備える画像処理装置。
(18)
符号化される画像の画素の色差成分の予測値を、対応する輝度成分の値の関数を用いて生成することと、
前記関数の係数を、前記画素が属するブロックの周辺の画素を参照して算出することと、
前記係数の算出の際に使用される参照画素数の前記ブロックのブロックサイズに対する比率を制御することと、
を含む画像処理方法。
(19)
復号される画像の輝度成分を用いて前記画像の色差成分のイントラ予測を行う予測部と、
前記予測部によりイントラ予測が行われる際に参照される参照画素を可変的に制御する制御部と、
を備える画像処理装置。
(20)
復号される画像の輝度成分を用いて前記画像の色差成分のイントラ予測を行うことと、
前記色差成分のイントラ予測が行われる際に参照される参照画素を可変的に制御することと、
を含む画像処理方法。
42 予測制御部
44 係数算出部(間引き部)
46 予測部
60 画像復号装置(画像処理装置)
92 予測制御部
94 係数算出部(間引き部)
96 予測部
Claims (20)
- 復号される画像の画素の色差成分の予測値を、対応する輝度成分の値の関数を用いて生成する予測部と、
前記予測部により使用される前記関数の係数を、前記画素が属するブロックの周辺の画素を参照して算出する係数算出部と、
前記ブロックのブロックサイズに対する前記係数算出部により使用される参照画素数の比率を制御する制御部と、
を備える画像処理装置。 - 前記制御部は、前記ブロックサイズに応じて前記比率を制御する、請求項1に記載の画像処理装置。
- 前記制御部は、前記ブロックサイズが第1のサイズである場合の前記比率を、前記ブロックサイズが前記第1のサイズよりも小さい第2のサイズである場合の前記比率よりも小さくなるように制御する、請求項2に記載の画像処理装置。
- 前記制御部は、前記ブロックサイズが所定のサイズを上回る場合に前記参照画素数が一定となるように、前記比率を制御する、請求項3に記載の画像処理装置。
- 前記係数算出部は、前記所定のサイズを上回る複数のブロックサイズについて共通的な回路又はロジックを用いて前記係数を算出する、請求項4に記載の画像処理装置。
- 前記制御部は、ブロックサイズと前記比率との間の予め定義されるマッピングに従って、前記比率を制御する、請求項1に記載の画像処理装置。
- 前記制御部は、前記係数の算出の際に間引かれる参照画素の数を変化させることにより、前記比率を制御する、請求項1に記載の画像処理装置。
- 前記制御部は、前記ブロックサイズが所定のサイズを下回る場合には、間引かれる参照画素の数をゼロとする、請求項7に記載の画像処理装置。
- 前記制御部は、前記ブロックの垂直方向のサイズに対する前記ブロックの左の参照画素数の比率である第1の比率と、前記ブロックの水平方向のサイズに対する前記ブロックの上の参照画素数の比率である第2の比率とを別々に制御する、請求項1に記載の画像処理装置
- 前記制御部は、同じブロックサイズについて前記第1の比率が前記第2の比率以下となるように前記第1の比率又は前記第2の比率を制御する、請求項9に記載の画像処理装置。
- 前記制御部は、短距離イントラ予測法が用いられる場合には、前記第1の比率及び前記第2の比率のうちサイズのより大きい方向に対応する比率のみを制御する、請求項9に記載の画像処理装置。
- 前記制御部は、前記色差成分の解像度を表すクロマフォーマットが4:2:2である場合に、前記ブロックの左の参照画素数が前記ブロックの上の参照画素数と等しくなるように、前記第1の比率を制御する、請求項9に記載の画像処理装置。
- 前記制御部は、前記色差成分の解像度を表すクロマフォーマットに応じて前記比率を制御する、請求項1に記載の画像処理装置。
- 前記制御部は、前記クロマフォーマットが第1の解像度を表している場合の前記比率を、前記クロマフォーマットが前記第1の解像度よりも低い第2の解像度を表している場合の前記比率よりも小さくなるように制御する、請求項13に記載の画像処理装置。
- 前記係数算出部は、画素値のビット深度が所定のビット数を上回る場合に、前記所定のビット数に削減された参照画素の画素値を用いて前記係数を算出する、請求項5に記載の画像処理装置。
- 復号される画像の画素の色差成分の予測値を、対応する輝度成分の値の関数を用いて生成することと、
前記関数の係数を、前記画素が属するブロックの周辺の画素を参照して算出することと、
前記係数の算出の際に使用される参照画素数の前記ブロックのブロックサイズに対する比率を制御することと、
を含む画像処理方法。 - 符号化される画像の画素の色差成分の予測値を、対応する輝度成分の値の関数を用いて生成する予測部と、
前記予測部により使用される前記関数の係数を、前記画素が属するブロックの周辺の画素を参照して算出する係数算出部と、
前記ブロックのブロックサイズに対する前記係数算出部により使用される参照画素数の比率を制御する制御部と、
を備える画像処理装置。 - 符号化される画像の画素の色差成分の予測値を、対応する輝度成分の値の関数を用いて生成することと、
前記関数の係数を、前記画素が属するブロックの周辺の画素を参照して算出することと、
前記係数の算出の際に使用される参照画素数の前記ブロックのブロックサイズに対する比率を制御することと、
を含む画像処理方法。 - 復号される画像の輝度成分を用いて前記画像の色差成分のイントラ予測を行う予測部と、
前記予測部によりイントラ予測が行われる際に参照される参照画素を可変的に制御する制御部と、
を備える画像処理装置。 - 復号される画像の輝度成分を用いて前記画像の色差成分のイントラ予測を行うことと、
前記色差成分のイントラ予測が行われる際に参照される参照画素を可変的に制御することと、
を含む画像処理方法。
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2013065678A1 (ja) * | 2011-10-31 | 2013-05-10 | 三菱電機株式会社 | 動画像符号化装置、動画像復号装置、動画像符号化方法及び動画像復号方法 |
US10148959B2 (en) * | 2014-03-11 | 2018-12-04 | Sony Corporation | Image coding device and method, and image decoding device and method |
US10362305B2 (en) | 2015-03-27 | 2019-07-23 | Sony Corporation | Image processing device, image processing method, and recording medium |
Families Citing this family (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2013034162A (ja) * | 2011-06-03 | 2013-02-14 | Sony Corp | 画像処理装置及び画像処理方法 |
KR20130050900A (ko) * | 2011-11-08 | 2013-05-16 | 한국전자통신연구원 | 인트라 예측 방법 및 그 장치 |
US9956687B2 (en) | 2013-03-04 | 2018-05-01 | Microsoft Technology Licensing, Llc | Adapting robot behavior based upon human-robot interaction |
BR112015025113B1 (pt) | 2013-04-05 | 2023-03-21 | Mitsubishi Electric Corporation | Dispositivo de decodificação de imagem a cores, e, método de decodificação de imagem a cores |
WO2015005418A1 (ja) | 2013-07-10 | 2015-01-15 | Kddi株式会社 | 動画像符号化装置、動画像復号装置、動画像システム、動画像符号化方法、動画像復号方法、およびプログラム |
CN104918050B (zh) * | 2014-03-16 | 2019-11-08 | 上海天荷电子信息有限公司 | 使用动态排列重组的参考像素样值集的图像编解码方法 |
US9923004B2 (en) * | 2014-09-30 | 2018-03-20 | Qualcomm Incorporated | Hardware acceleration of computer vision feature detection |
KR102264163B1 (ko) | 2014-10-21 | 2021-06-11 | 삼성전자주식회사 | 텍스쳐를 처리하는 방법 및 장치 |
US9743092B2 (en) * | 2015-10-13 | 2017-08-22 | Nokia Technologies Oy | Video coding with helper data for spatial intra-prediction |
US10475238B2 (en) * | 2016-07-25 | 2019-11-12 | University Of Toronto | Hölder adaptive image synthesis |
US9712830B1 (en) | 2016-09-15 | 2017-07-18 | Dropbox, Inc. | Techniques for image recompression |
CN116962687A (zh) * | 2016-11-29 | 2023-10-27 | 成均馆大学校产学协力团 | 影像编码/解码方法、装置以及对比特流进行存储的记录介质 |
CN109274969B (zh) * | 2017-07-17 | 2020-12-22 | 华为技术有限公司 | 色度预测的方法和设备 |
WO2019059107A1 (ja) * | 2017-09-20 | 2019-03-28 | パナソニック インテレクチュアル プロパティ コーポレーション オブ アメリカ | 符号化装置、復号装置、符号化方法及び復号方法 |
CN110719479B (zh) * | 2018-07-15 | 2023-01-10 | 北京字节跳动网络技术有限公司 | 跨分量编码信息导出 |
CN110858903B (zh) * | 2018-08-22 | 2022-07-12 | 华为技术有限公司 | 色度块预测方法及装置 |
CN110876061B (zh) * | 2018-09-03 | 2022-10-11 | 华为技术有限公司 | 色度块预测方法及装置 |
CN117834862A (zh) * | 2018-09-20 | 2024-04-05 | Lg电子株式会社 | 图像解码、编码方法和数据的发送方法及存储介质 |
KR20210089131A (ko) | 2018-11-06 | 2021-07-15 | 베이징 바이트댄스 네트워크 테크놀로지 컴퍼니, 리미티드 | 위치 기반 인트라 예측 |
WO2020108591A1 (en) | 2018-12-01 | 2020-06-04 | Beijing Bytedance Network Technology Co., Ltd. | Parameter derivation for intra prediction |
GB2580192A (en) | 2018-12-20 | 2020-07-15 | Canon Kk | Piecewise modeling for linear component sample prediction |
GB2580326A (en) | 2018-12-28 | 2020-07-22 | British Broadcasting Corp | Video encoding and video decoding |
GB2591806B (en) * | 2020-02-07 | 2023-07-19 | British Broadcasting Corp | Chroma intra prediction in video coding and decoding |
CN111914938B (zh) * | 2020-08-06 | 2024-01-30 | 上海金桥信息股份有限公司 | 一种基于全卷积二分支网络的图像属性分类识别方法 |
TWI816166B (zh) * | 2021-04-22 | 2023-09-21 | 滿拓科技股份有限公司 | 偵測物件深度和水平距離的方法及系統 |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH09247673A (ja) * | 1996-03-04 | 1997-09-19 | Kokusai Denshin Denwa Co Ltd <Kdd> | 符号化動画像再生装置 |
JP2003289544A (ja) * | 2002-03-27 | 2003-10-10 | Sony Corp | 画像情報符号化装置及び方法、画像情報復号装置及び方法、並びにプログラム |
JP2007214641A (ja) * | 2006-02-07 | 2007-08-23 | Seiko Epson Corp | 符号化装置、復号化装置、画像処理装置及び画像処理方法をコンピュータに実行させるためのプログラム |
WO2011125868A1 (ja) * | 2010-04-09 | 2011-10-13 | ソニー株式会社 | 画像処理装置および方法 |
Family Cites Families (39)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2003037843A (ja) * | 2001-07-23 | 2003-02-07 | Sony Corp | 画像処理装置および方法、記録媒体、並びにプログラム |
CN100420308C (zh) * | 2002-04-26 | 2008-09-17 | 株式会社Ntt都科摩 | 图象编码装置和图象译码装置 |
KR20060105408A (ko) * | 2005-04-01 | 2006-10-11 | 엘지전자 주식회사 | 영상 신호의 스케일러블 인코딩 및 디코딩 방법 |
CN1615019A (zh) * | 2003-11-05 | 2005-05-11 | 华为技术有限公司 | 一种视频宏块模式编码方法 |
US7511714B1 (en) * | 2003-11-10 | 2009-03-31 | Nvidia Corporation | Video format conversion using 3D graphics pipeline of a GPU |
JP4747494B2 (ja) * | 2004-03-03 | 2011-08-17 | ソニー株式会社 | データ処理装置およびその方法と符号化装置 |
US7649539B2 (en) * | 2004-03-10 | 2010-01-19 | Microsoft Corporation | Image formats for video capture, processing and display |
JP2005348093A (ja) * | 2004-06-03 | 2005-12-15 | Sony Corp | 画像処理装置、そのプログラムおよびその方法 |
US20060002468A1 (en) * | 2004-06-22 | 2006-01-05 | Minhua Zhou | Frame storage method |
KR101182977B1 (ko) * | 2004-06-29 | 2012-09-18 | 소니 주식회사 | 움직임 예측 보상 방법 및 움직임 예측 보상 장치 |
KR100695141B1 (ko) * | 2005-02-15 | 2007-03-14 | 삼성전자주식회사 | 영상처리시스템에 있어서 메모리 억세스장치 및 방법, 데이터 기록장치 및 방법과 데이터 독출장치 및 방법 |
US7747096B2 (en) * | 2005-07-15 | 2010-06-29 | Samsung Electronics Co., Ltd. | Method, medium, and system encoding/decoding image data |
KR101424969B1 (ko) * | 2005-07-15 | 2014-08-04 | 삼성전자주식회사 | 영상 복호화 방법 |
US8509551B2 (en) * | 2005-07-22 | 2013-08-13 | Mitsubishi Electric Corporation | Image encoder and image decoder, image encoding method and image decoding method, image encoding program and image decoding program, and computer readable recording medium recording with image encoding program and computer readable recording medium recorded with image decoding program |
US8488889B2 (en) * | 2005-07-22 | 2013-07-16 | Mitsubishi Electric Corporation | Image encoder and image decoder, image encoding method and image decoding method, image encoding program and image decoding program, and computer readable recording medium recorded with image encoding program and computer readable recording medium recorded with image decoding program |
CN100417228C (zh) * | 2005-10-31 | 2008-09-03 | 连展科技(天津)有限公司 | 一种基于h.264/avc标准的帧图像的帧内预测模式选择方法 |
US7372469B2 (en) * | 2006-04-12 | 2008-05-13 | Arcadyan Technology Corporation | Image transforming method |
JP4747975B2 (ja) * | 2006-07-14 | 2011-08-17 | ソニー株式会社 | 画像処理装置および方法、プログラム、並びに、記録媒体 |
CN101193305B (zh) * | 2006-11-21 | 2010-05-12 | 安凯(广州)微电子技术有限公司 | 用于视频编解码芯片中帧内预测的数据存储和交换方法 |
US20080123750A1 (en) * | 2006-11-29 | 2008-05-29 | Michael Bronstein | Parallel deblocking filter for H.264 video codec |
CN101198051B (zh) | 2006-12-07 | 2011-10-05 | 深圳艾科创新微电子有限公司 | 基于h.264的熵解码器的实现方法及装置 |
KR101365569B1 (ko) * | 2007-01-18 | 2014-02-21 | 삼성전자주식회사 | 인트라 예측 부호화, 복호화 방법 및 장치 |
US8837575B2 (en) * | 2007-03-29 | 2014-09-16 | Cisco Technology, Inc. | Video processing architecture |
JP5369425B2 (ja) * | 2007-10-31 | 2013-12-18 | 富士通株式会社 | 画像復元装置、画像復元プログラム、画像復元方法 |
CN101222646B (zh) * | 2008-01-30 | 2010-06-02 | 上海广电(集团)有限公司中央研究院 | 一种适用于avs编码的帧内预测装置及预测方法 |
CN101304528B (zh) * | 2008-06-10 | 2010-11-17 | 浙江大学 | 视频处理器视频数据与存储器存储空间的映射方法 |
US8666182B2 (en) * | 2008-08-13 | 2014-03-04 | University-Industry Cooperation Group Of Kyung-Hee University | Method for generating thumbnail image in image frame of the H.264 standard |
US8265152B2 (en) * | 2008-10-10 | 2012-09-11 | Arecont Vision, Llc. | System and method for low-latency processing of intra-frame video pixel block prediction |
KR101127962B1 (ko) * | 2008-12-22 | 2012-03-26 | 한국전자통신연구원 | 영상 처리 장치 및 영상 처리를 위한 프레임 메모리 관리 방법 |
US8542938B2 (en) * | 2008-12-31 | 2013-09-24 | Entropic Communications, Inc. | System and method for intra-frame compression using predictive coding |
JP5597968B2 (ja) * | 2009-07-01 | 2014-10-01 | ソニー株式会社 | 画像処理装置および方法、プログラム、並びに記録媒体 |
US9288500B2 (en) * | 2011-05-12 | 2016-03-15 | Texas Instruments Incorporated | Luma-based chroma intra-prediction for video coding |
JP2013034162A (ja) * | 2011-06-03 | 2013-02-14 | Sony Corp | 画像処理装置及び画像処理方法 |
JP2013034163A (ja) * | 2011-06-03 | 2013-02-14 | Sony Corp | 画像処理装置及び画像処理方法 |
EP3843396B1 (en) * | 2011-09-28 | 2023-01-25 | Sun Patent Trust | Image decoding method and image coding and decoding method |
JP2013150173A (ja) * | 2012-01-19 | 2013-08-01 | Sony Corp | 画像処理装置および方法 |
US9503724B2 (en) * | 2012-05-14 | 2016-11-22 | Qualcomm Incorporated | Interleave block processing ordering for video data coding |
US20170332103A1 (en) * | 2016-05-13 | 2017-11-16 | Intel Corporation | Interleaving luma and chroma coefficients to reduce the intra prediction loop dependency in video encoders and decoders |
US20180131936A1 (en) * | 2016-11-10 | 2018-05-10 | Intel Corporation | Conversion buffer to decouple normative and implementation data path interleaving of video coefficients |
-
2011
- 2011-09-27 JP JP2011210542A patent/JP2013034162A/ja not_active Withdrawn
-
2012
- 2012-03-30 TW TW101111511A patent/TW201251468A/zh unknown
- 2012-04-04 AU AU2012263915A patent/AU2012263915A1/en not_active Abandoned
- 2012-04-04 BR BR112013030378A patent/BR112013030378A2/pt not_active IP Right Cessation
- 2012-04-04 MX MX2013013764A patent/MX2013013764A/es not_active Application Discontinuation
- 2012-04-04 CN CN201280025736.3A patent/CN103563383B/zh active Active
- 2012-04-04 RU RU2013152459/08A patent/RU2013152459A/ru unknown
- 2012-04-04 CN CN201611063833.8A patent/CN106878710A/zh active Pending
- 2012-04-04 KR KR1020137027399A patent/KR20140019388A/ko not_active Application Discontinuation
- 2012-04-04 CA CA2837043A patent/CA2837043A1/en not_active Abandoned
- 2012-04-04 CN CN201611063563.0A patent/CN106878709A/zh active Pending
- 2012-04-04 EP EP12793497.4A patent/EP2717578A1/en not_active Withdrawn
- 2012-04-04 CN CN201611063566.4A patent/CN106888378A/zh active Pending
- 2012-04-04 US US14/003,253 patent/US9153040B2/en active Active
- 2012-04-04 WO PCT/JP2012/059168 patent/WO2012165039A1/ja active Application Filing
-
2015
- 2015-07-29 US US14/812,282 patent/US9569861B2/en active Active
-
2016
- 2016-11-25 US US15/361,165 patent/US10666945B2/en active Active
- 2016-11-25 US US15/361,154 patent/US10652546B2/en active Active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH09247673A (ja) * | 1996-03-04 | 1997-09-19 | Kokusai Denshin Denwa Co Ltd <Kdd> | 符号化動画像再生装置 |
JP2003289544A (ja) * | 2002-03-27 | 2003-10-10 | Sony Corp | 画像情報符号化装置及び方法、画像情報復号装置及び方法、並びにプログラム |
JP2007214641A (ja) * | 2006-02-07 | 2007-08-23 | Seiko Epson Corp | 符号化装置、復号化装置、画像処理装置及び画像処理方法をコンピュータに実行させるためのプログラム |
WO2011125868A1 (ja) * | 2010-04-09 | 2011-10-13 | ソニー株式会社 | 画像処理装置および方法 |
Non-Patent Citations (10)
Title |
---|
JIANLE CHEN ET AL.: "CE6.a.4: Chroma intra prediction by reconstructed luma samples", JCTVC-E266, March 2011 (2011-03-01) |
JIANLE CHEN ET AL.: "CE6.a.4: Chroma intra prediction by reconstructed luma samples", JOINT COLLABORATIVE TEAM ON VIDEO CODING (JCT-VC) OF ITU-T SG16 WP3 AND ISO/IEC JTC1/ SC29/WG11 5TH MEETING, March 2011 (2011-03-01), GENEVA, XP030048360 * |
JIANLE CHEN ET AL.: "CE6.a: Chroma intra prediction by reconstructed luma samples", JOINT COLLABORATIVE TEAM ON VIDEO CODING (JCT-VC) OF ITU-T SG16 WP3 AND ISO/IEC JTC1/SC29/WG11 4TH MEETING, January 2011 (2011-01-01), DAEGU, KR, XP030047683 * |
JIANLE CHEN ET AL.: "Chroma intra prediction by reconstructed luma samples", JOINT COLLABORATIVE TEAM ON VIDEO CODING (JCT-VC) OF ITU-T SG16 WP3 AND ISO/IEC JTC1/SC29/WG11 3RD MEETING, October 2010 (2010-10-01), GUANGZHOU, CN, XP055060342 * |
KAZUSHI SATO: "Complexity Reduction of Chroma Intra Prediction by Reconstructed Luma Samples", JOINT COLLABORATIVE TEAM ON VIDEO CODING (JCT-VC) OF ITU-T SG16 WP3 AND ISO/IEC JTC1/ SC29/WG11 6TH MEETING, July 2011 (2011-07-01), TORINO, IT, XP030049424 * |
SAN HEON LEE ET AL.: "Intra prediction method based on the linear relationship between the channels for YUV 4:2:0 intra coding", 16TH IEEE INTERNATIONAL CONFERENCE ON IMAGE PROCESSING (ICIP), 7 November 2009 (2009-11-07), pages 1037 - 1040, XP031628426 * |
SEUNG WOOK PARK ET AL.: "New intra chroma prediction using inter-channel correlation", JOINT COLLABORATIVE TEAM ON VIDEO CODING (JCT-VC) OF ITU-T SG16 WP3 AND ISO/IEC JTC1/ SC29/WG11 2ND MEETING, July 2010 (2010-07-01), GENEVA, XP030007601 * |
SUNG-CHANG LIM; HAHYUN LEE; JINHO LEE; JONGHO KIM; HAECHUL CHOI; SEYOON JEONG; JIN SOO CHOI: "Intra coding using extended block size", VCEG-AL, vol. 28, July 2009 (2009-07-01) |
XIAORAN CAO ET AL.: "CE6.bl Report on Short Distance Intra Prediction Method", JOINT COLLABORATIVE TEAM ON VIDEO CODING (JCT-VC) OF ITU-T SG16 WP3 AND ISO/IEC JTC1/SC29/WG11 5TH MEETING, March 2011 (2011-03-01), GENEVA, XP030048372 * |
XIAORAN CAO TSINGHUA ET AL.: "CE6.b1 Report on Short Distance Intra Prediction Method", JCTVC-E278, March 2011 (2011-03-01) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2013065678A1 (ja) * | 2011-10-31 | 2013-05-10 | 三菱電機株式会社 | 動画像符号化装置、動画像復号装置、動画像符号化方法及び動画像復号方法 |
US10148959B2 (en) * | 2014-03-11 | 2018-12-04 | Sony Corporation | Image coding device and method, and image decoding device and method |
US10362305B2 (en) | 2015-03-27 | 2019-07-23 | Sony Corporation | Image processing device, image processing method, and recording medium |
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US20170078685A1 (en) | 2017-03-16 |
KR20140019388A (ko) | 2014-02-14 |
CN106878710A (zh) | 2017-06-20 |
US20150334392A1 (en) | 2015-11-19 |
US10666945B2 (en) | 2020-05-26 |
CN103563383A (zh) | 2014-02-05 |
RU2013152459A (ru) | 2015-06-10 |
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