EP1889487A1 - Procede de codage video fonde sur des couches multiples, procede de decodage, codeur video, et decodeur video utilisant une prevision de lissage - Google Patents
Procede de codage video fonde sur des couches multiples, procede de decodage, codeur video, et decodeur video utilisant une prevision de lissageInfo
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- EP1889487A1 EP1889487A1 EP06768807A EP06768807A EP1889487A1 EP 1889487 A1 EP1889487 A1 EP 1889487A1 EP 06768807 A EP06768807 A EP 06768807A EP 06768807 A EP06768807 A EP 06768807A EP 1889487 A1 EP1889487 A1 EP 1889487A1
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
- H04N19/85—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using pre-processing or post-processing specially adapted for video compression
- H04N19/86—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using pre-processing or post-processing specially adapted for video compression involving reduction of coding artifacts, e.g. of blockiness
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- H—ELECTRICITY
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- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
- H04N19/10—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
- H04N19/102—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the element, parameter or selection affected or controlled by the adaptive coding
- H04N19/103—Selection of coding mode or of prediction mode
- H04N19/105—Selection of the reference unit for prediction within a chosen coding or prediction mode, e.g. adaptive choice of position and number of pixels used for prediction
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- H04N19/169—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
- 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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- H04N19/10—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
- H04N19/169—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
- H04N19/187—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 a scalable video layer
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- H04N19/82—Details of filtering operations specially adapted for video compression, e.g. for pixel interpolation involving filtering within a prediction loop
Definitions
- Apparatuses and methods consistent with the present invention relates generally to video coding technology and, more particularly, to a method and apparatus for decreasing block artifacts in multilayer-based video coding.
- Data can be compressed by eliminating spatial redundancy, such as the case where the same color or object is repeated in an image, temporal redundancy, such as the case where there is little change between neighboring frames or the same audio sound is repeated, or psychovisual redundancy in which the fact that humans' visual and perceptual abilities are insensitive to high frequencies is taken into account.
- spatial redundancy such as the case where the same color or object is repeated in an image
- temporal redundancy such as the case where there is little change between neighboring frames or the same audio sound is repeated
- psychovisual redundancy in which the fact that humans' visual and perceptual abilities are insensitive to high frequencies is taken into account.
- temporal redundancy is eliminated using temporal filtering based on motion compensation
- spatial redundancy is eliminated using spatial transform.
- transmission media are necessary. Performance differs according to transmission medium.
- Currently used transmission media have various transmission speeds ranging from the speed of an ultra high-speed communication network, which can transmit data at a transmission rate of several tens of megabits per second, to the speed of a mobile communication network, which can transmit data at a transmission rate of 384 Kbits per second.
- a scalable video encoding method which can support transmission media having a variety of speeds or can transmit multimedia at a transmission speed suitable for each transmission environment, is required.
- Such a scalable video coding method refers to a coding method that allows a video resolution, a frame rate, a Signal-to-Noise Ratio (SNR), etc. to be adjusted by truncating part of an already compressed bitstream in conformity with surrounding conditions, such as a transmission bit rate, a transmission error rate, a system source, etc.
- SNR Signal-to-Noise Ratio
- JVT Joint Video Team
- MPEG Moving Picture Experts Group
- ITU International Telecommunication Union
- the H.264 SE and a multilayer-based scalable video codec basically support four prediction modes, that is, inter prediction, directional intra prediction (hereinafter simply referred to as 'intra prediction'), residual prediction and intra-base prediction.
- 'intra prediction' directional intra prediction
- residual prediction residual prediction
- intra-base prediction intra-base prediction.
- 'prediction' implies a technique of compressively representing original data using prediction data generated based on information that can be commonly used in an encoder and a decoder.
- Inter predictions are classified into bi-directional prediction for which two reference pictures are used, forward prediction for which a previous reference picture is used, and backward prediction for which a subsequent reference picture is used, according to the method of making reference to a reference picture.
- the intra-base prediction may be used in the case where a lower layer picture
- a 'base picture' having a temporal location identical to a current picture, exists in a video codec having a multi-layer structure.
- the macroblock of the current picture can be efficiently predicted from the macroblock of the base picture corresponding to the macroblock of the current picture. That is, a difference between the macroblock of the current picture and the macroblock of the base picture is quantized.
- inter prediction with residual prediction (hereinafter simply called 'residual prediction') is a prediction method in which the existing inter prediction in a single layer is extended to a multilayer form. According to the residual prediction method of FIG. 3, a difference generated by the current layer inter prediction process is not directly quantized, a difference generated by the current layer and a difference generated by a lower layer inter prediction process are subtracted from each other again, and a result obtained by the subtraction is quantized.
- the most efficient of the above-described four prediction methods is used for respective macroblocks forming a picture.
- the inter prediction and the residual prediction may be chiefly used for a video sequence in which motion is slow.
- the intra-base prediction may be chiefly used for a video sequence in which motion is fast.
- the video codec having the multi-layer structure has a relatively complicated prediction structure compared to a video codec having a single-layer structure and chiefly employs an open-loop structure, so that a lot of block artifacts appear in contrast to the codec having the single-layer structure.
- the above- described residual prediction uses the residual signals of the lower layer picture, so that excessive distortion may occur in the case where the characteristics of the residual signals are greatly different from those of the inter prediction signals of the current layer picture.
- prediction signals for the macroblock of the current picture are not original signals, and are restored signals after quanization. Accordingly, the prediction signals are signals that can be obtained in common by both an encoder and a decoder, so that encoder-decoder mismatch does not occur. In particular, a difference with the macroblock of the current picture is obtained using a smoothing filter for the prediction signals, so that block artifacts are considerably reduced. Disclosure of Invention
- H.264 SE allows intra-base prediction to be used in the case where a specific condition is satisfied, so that only decoding can be performed in a manner similar to that in a video codec having a single-layer structure, although encoding is performed in a multi-layer form.
- aspect of the present invention relates to improving coding performance when inter prediction or residual prediction is performed in a multilayer- based video codec.
- the present invention provides a multilayer-based video encoding method, including the steps of (a) calculating a difference between an inter prediction block for the block of a lower layer picture, which corresponds to an arbitrary block of a current picture, and the block of the lower layer picture; (b) adding the calculated difference to an inter prediction block for the block of the current picture; (c) smoothing a block, which is generated by the adding, using a smoothing filter; and (d) encoding a difference between the block of the current picture and a block generated by the smoothing.
- the present invention provides a multilayer-based video encoding method, including the steps of (a) generating an inter prediction block for an arbitrary block of a current picture; (b) smoothing the generated inter prediction block using a smoothing filter; (c) calculating a difference between the block of the current picture and a block generated by the smoothing; and (d) encoding a difference.
- the present invention provides a multilayer-based video decoding method, comprising the steps of (a) restoring the residual signals of an arbitrary block of a current picture, which is contained in an input bitstream, based on texture data for the block of the current picture; (b) restoring the residual signals of the block of a lower layer picture, which is contained in the bitstream and corresponds to the block of the current picture; (c) adding the residual signals, which are restored at step (b), to an inter prediction block for the current picture; (d) smoothing a block, which is generated by the adding, using a smoothing filter; and (e) adding the residual signals, which are restored at step (a), to a block generated by the smoothing.
- the present invention also provides a multilayer-based video encoder, including a means for generating an inter prediction block for an arbitrary block of a current picture; a means for smoothing the generated inter prediction block using a smoothing filter; a means for calculating a difference between the block of the current picture and a block generated by the smoothing; and a means for encoding a difference.
- the present invention further provides a multilayer-based video encoder, including a means for restoring the residual signals of an arbitrary block of a current picture, which is contained in an input bitstream, based on texture data for the block of the current picture; a means for restoring the residual signals of the block of a lower layer picture, which is contained in the bitstream and corresponds to the block of the current picture; a means for adding the residual signals, which are restored at step (b), to an inter prediction block for the current picture; a means for smoothing a block generated by the adding using a smoothing filter; and a means for adding the residual signals, which are restored at step (a), to a block generated by the smoothing.
- FlG. 1 is a diagram illustrating a related method
- FlG. 2 is a diagram illustrating a related intra-base prediction method
- FlG. 3 is a diagram illustrating a related residual prediction method
- FlG. 4 is a diagram illustrating a smoothing prediction method according to an exemplary embodiment of the present invention.
- FlG. 6 is a diagram showing an example of applying a smoothing filter to the lateral boundary of a sub-block having a size of 4 x 4 pixels;
- FlG. 7 is a block diagram showing the construction of a video encoder according to an exemplary embodiment of the present invention.
- FlG. 8 a block diagram showing the construction of a video decoder according to an exemplary embodiment of the present invention.
- FlG. 9 is a diagram showing the construction of a system for implementing the video encoder of FlG. 7 and the video decoder of FIG. 8. Mode for Invention
- R r O 1 , - P F ⁇ R R (1)
- Equations 1 and 2 are compared to each other, they seem not to have a common point at first glance. However, when the equations are expressed by the following Equations 3 and 4, respectively, the similarity there between can be found.
- Equation 4 the symbol U indicates an up-sampling function, and the symbol B indicates a deblock function. Since the up-sampling function is used in the case where the resolution of the current layer and the resolution of the lower layer are different from each other, the up-sampling function is expressed by the symbol [U] in the sense that it can be selectively used.
- Equation 3 the inter prediction block P of the lower layer is used in Equation 4.
- Equation 3 the existing residual prediction can be complemented.
- Equation 5 A prediction mode based on Equation 5 may be applied to the inter prediction without change. That is, the prediction mode can be regarded as the case where the R B is 0 in the inter prediction, R can be expressed by the following Equation 6:
- a method of employing the smoothing filter when the existing residual prediction or inter prediction is performed is defined as the term 'smoothing prediction'.
- a process of performing the smoothing prediction is described in more detail with reference to FIG. 4.
- FIG. 4 a process of encoding an arbitrary block of the current picture 20 (hereinafter referred to as a 'current block') is exemplified.
- the block 10 in the base picture, which corresponds to the current block 20, is named 'base block.'
- the inter prediction block 13 for the base block 10 is generated using the base block 10, and blocks 11 and 12 in the neighboring reference pictures (forward reference picture and backward reference picture) of the lower layer, which correspond to the base block 10 based on motion vectors. Thereafter, a difference (corresponding to R in Equation 5) between the base block 10 and the prediction
- the inter prediction block 23, generated based on the current layer, is smoothened using the smoothing filter, and then a difference between the current block 20 and a block (corresponding to F(P ) in Equation 6) generated by the smoothing is quantized.
- the smoothing function (F) may be formed of only the deblock function (B) in the simplest manner, or includes the deblock function (B) and functions (U-D).
- F is a function applied to the resolution of the current layer
- the down- sampling function (D) is applied prior to the application of the up-sampling function (U).
- (U) chiefly performs a smoothing task, the tasks overlap each other. Furthermore, the deblock function, the up-sampling function, and the down-sampling function require the considerable amount of operations at the time of application, and the down- sampling function assumes a role of very strong low-pass filtering, so that the details of an image obtained when prediction is performed can be deteriorated.
- the smoothing filter (F) allows boundary pixels and their neighboring pixels to be represented in a linear coupling form so that the process of applying the smoothing filter is performed by a small amount of operations.
- FIGS. 5 and 6 are diagrams illustrating the application examples of the smoothing filter, and show examples of applying the smoothing filter to the vertical boundary and lateral boundary of sub-blocks, each having a 4x4 size.
- boundary pixels x(n-l) and x(n) can be smoothened in a form in which the boundary pixels and their neighboring pixels are linearly coupled.
- x'(n-l) ⁇ *x(n-2) + ⁇ *x(n-l ) + ⁇ *x(n)
- x'(n) ⁇ *x(n-l) + ⁇ *x(n) + ⁇ *x(n+l) (8)
- ⁇ *, ⁇ *, and ⁇ * can be appropriately selected such that the sum thereof is 1.
- the weighted value of a corresponding pixel can increase in contrast to neighboring pixels.
- a further host of pixels may be selected to be neighboring pixels.
- the smoothing prediction method described above may be selectively used along with the four existing prediction methods.
- the reason that the smoothing prediction method is selectively used is because the smoothing prediction method exerts an effect when it is used for an image for which the characteristics of the blocks P F and R B do not match each other well, while the deterioration of performance may result when the smoothing prediction method is used for an image for which the characteristics of the blocks P and R match each other.
- flags are respectively provided for macroblocks, and the encoder is allowed to selectively use the smoothing prediction method and the existing prediction methods based on the values of the flags.
- the decoder reads the flags, thus determining whether the smoothing prediction has been used.
- the number of blocks from which artifacts occur is not too many in contrast to overall blocks, so that it is expected that a image quality improvement effect, which can be acquired by eliminating the block artifacts, is greater than that acquired from overhead bits that occur due to the adding of the flags.
- FlG. 7 is a block diagram showing the construction of a video encoder 100 according to an exemplary embodiment of the present invention.
- a block identifier is represented using a subscript of character 'F' that indicates a picture.
- a picture, including a block R is represented by F
- a current picture F is input to a motion estimation unit 105, a buffer 101, a subtractor 115, and a down-sampler 103.
- the down-sampler 103 performs spatial and/or temporal down-sampling on the current picture F and generates a lower layer picture F .
- a motion estimation unit 205 performs motion estimation on the lower layer picture F with reference to neighboring pictures F , thus obtaining motion vectors
- a block matching algorithm is widely used to performs motion estimation. That is, a displacement, obtained when an error is minimized while moving a given block within the specific search area of a reference picture on a pixel basis or a sub- pixel (2/2 pixel, 1/4 pixel, etc.) basis, is estimated as a motion vector.
- a fixed-size block matching method may be used to perform motion estimation, and a hierarchical method based on a Hierarchical Variable Size Block Matching (HVSBM), such as H.264, may also be used.
- HVSBM Hierarchical Variable Size Block Matching
- the motion vectors MV obtained by the motion estimation unit 205 are provided to a motion compensation unit 210.
- the motion compensation unit 210 compensates for the motion of the reference picture FOB' using the motion vectors MV and
- the prediction picture F is composed of a plurality of inter prediction blocks
- a subtractor 215 calculates a difference between the lower layer picture
- a difference calculation process may be referred to as a process of calculating a difference between a block O B , which is contained in the lower layer picture F , and a residual block R , which is contained in the prediction picture F .
- the prediction picture F is provided to an adder 135. If the resolutions of layers are different to each other, the prediction picture FPB is up-sampled to the resolution of a current layer by an up-sampler 140 and is then provided to the adder 135.
- the current picture F is input to the motion estimation unit 105, the buffer 101, and the subtractor 115.
- the motion estimation unit 105 performs motion estimation on the current picture with reference to a neighboring picture reference, thus obtaining motion vectors MV . Since the process of performing motion estimation is the same as that occurring in the motion estimation unit 205, a repeated description is omitted.
- the motion vectors MV obtained by the motion estimation unit 105 are provided to a motion compensation unit 110.
- the motion compensation unit 110 compensates for the motion of a reference picture F using the motion vectors MV , and generates a prediction picture F for the current picture.
- an adder 135 adds the prediction picture F and the residual picture FR provided from the lower layer. From a point of view of a block basis, the addition
- B process may be referred to as a process of adding an inter prediction block P , which is contained in the prediction picture F , and the residual block R , which is contained in the residual picture F .
- a smoothing filter unit 130 smoothes the output F +F of the adder 135 using a smoothing filter.
- the smoothing function may have a form in which the boundary pixels of the smoothened block and their neighboring pixels are linearly coupled, as described in Equation 8.
- the neighboring pixels as shown in FIGS. 5 and 6, are pixels that neighbor the boundary pixels, a weighted value of each of the boundary pixels may be defined as 1/2, and a weighted value of each of the neighboring pixels may be defined as 1/4.
- the process of generating a difference may be referred to as a process of performing subtraction on the block O , which is contained in the current picture F , and a block (F(P +R ) of Equation 5, which is generated by the smoothing.
- the transform unit 120 performs spatial transform on the deferential picture F , and generates transform coefficients F .
- the spatial transform method may employ Discrete Cosine Transform (DCT), wavelet transform or the like.
- the transform coefficients may be DCT coefficients in the case where the DCT is used, and the transform coefficients may be wavelet coefficients in the case where the wavelet transform is used.
- the quantization unit 125 quantizes the transform coefficients.
- the quantization refers to a process of converting the transform coefficients, which are expressed by arbitrary real number values, into discrete values.
- the quantization unit 125 performs quantization in such a manner as to divide the transform coefficients, which are expressed by arbitrary real number values by a predetermined quantization step, and then round off the divided results to integer values.
- the residual picture F of the lower layer is converted into quantization coefficients F Q via a transform unit 220 and a quantization unit 225.
- the entropy encoding unit 150 encodes the motion vectors MV estimated by the motion estimation unit 105, the motion vectors MV estimated by the motion
- the bitstream may further include a flag for indicating whether the quantization co- efficients F Q have been encoded by the smoothing prediction proposed by the present invention, that is, whether the quantization coefficients F Q have been
- Equation 5 a process of actually implementing the numerical formula of Equation 5 has been described in conjunction with FIG. 7.
- the present invention is not limited to this, and may be implemented based on the numerical formula of Equation 6 in consideration of the case where R is set to '0' in Equation 5, that is, the characteristics of a single layer.
- This is a method that can be applied to the single layer, and may be implemented in such a manner that the operational process of the lower layer is omitted in FIG. 7, and the prediction picture F , which is output from the motion compensation unit 110, is directly input to the smoothing filter 130 without passing through the adder 135. Accordingly, a separate drawing is not provided.
- a video encoding method may include the steps of generating an inter prediction block for an arbitrary block of a current picture, smoothing the generated inter prediction block using a smoothing filter, calculating a difference between the block of the current picture and a block generated by the smoothing, and encoding a difference.
- FIG. 8 is a block diagram showing the construction of a video decoder 300 according to an exemplary embodiment of the present invention.
- An entropy decoding unit 305 decodes an input bitstream without loss, the texture data F Q of the current picture, the texture
- the lossless decoding is a process that is
- the texture data F Q of the current picture is provided to a dequantization unit
- An inverse transform unit 320 performs dequantization on the results of the de- quantization.
- the inverse transform process is performed in a reverse order to that of the transform process of the encoder and, specifically, may employ inverse DCT, inverse wavelet transform or the like.
- the residual picture F RF is composed of a plurality of residual signals R , that is, a plurality of residual blocks.
- a dequantization unit 410 de- quantizes the provided texture data F Q of the lower layer picture, and an inverse
- RB transform unit 420 performs inverse transform on the results of the dequantization. As the result of the transform, a residual picture F with respect to the lower layer picture
- the residual picture F is composed of a plurality of residual signals R . [89]
- the restored residual picture F is provided to an adder 360. In this case, when the
- the motion compensation unit 350 performs motion compensation on a reference picture F provided from a buffer 340 using the motion vectors MV , thus generating an inter prediction picture F .
- the reference picture F refers to the neighboring picture of the current picture, which was previously restored and then stored to the buffer 340.
- the adder 360 adds the prediction picture FPF to the residual picture F RB provided from the lower layer. From a view of point of a block basis, the addition process may be referred to as a process of adding an inter prediction block P , which is contained in the prediction picture F , and the residual block R , which is contained in the residual p ⁇ icture F RB . [93] Thereafter, the fourth step is described below.
- a smoothing filter 370 smoothes the output F +F of the adder 360 using a smoothing filter.
- a smoothing function for the smoothing filter may be implemented in various forms. For example, as described in Equation 7, when the resolutions of layers are the same, a deblock function may be used without change as the smoothing function for the smoothing filter. In contrast, when the resolutions of layers are different, a combination of a deblock function, a down-sampling function and an up-sampling function may be used as the smoothing function.
- the smoothing function may have a form in which the boundary pixels of the smoothened block and their neighboring pixels are linearly coupled, as described in Equation 8.
- the neighboring pixels as shown in FIGS. 5 and 6, are pixels that neighbor the boundary pixels, a weighted value of each of the boundary pixels may be defined as 1/2, and a weighted value of each of the neighboring pixels may be defined as 1/4.
- motion vectors of the current layer and MV (motion vectors of the lower layer) to the video decoder 300.
- the video encoder 100 only sends MV and the video decoder 300 uses the MV as motion vectors of the current layer.
- FIG. 9 is a diagram showing the construction of a system for implementing the video encoder 100 or the video decoder 300.
- the system may include a TV, set-top box, a desktop computer, a laptop computer, a palmtop computer, a Personal Digital Assistant (PDA), or a video or image storage device (for example, a Video Cassette Recorder (VCR), or a Digital Video Recorder (DVR)).
- the system may be formed of a combination of the above-described devices, or be formed such that one or more devices described above are contained in another device as part thereof.
- the system may include at least one video source 910, one or more input/output devices 920, a processor 940, memory 950, and a display device 930.
- the video source 910 may be a Television (TV) receiver, or a VCR or another video storage device. Furthermore, the source 910 may be one or more network connections for receiving video from a server using Internet, a Wide Area Network (WAN), a Local Area Network (LAN), a terrestrial broadcast system, a cable network, a satellite communication network, a wireless network, or a telephone network. Furthermore, the source may be formed of a combination of the above-described networks, or be formed such that one or more networks described-above are contained in another network as part thereof.
- WAN Wide Area Network
- LAN Local Area Network
- the source may be formed of a combination of the above-described networks, or be formed such that one or more networks described-above are contained in another network as part thereof.
- the input/output device 920, the processor 940, and the memory 950 perform communication through a communication medium 960.
- the communication medium 960 may be a communication bus, a communication network, or one or more internal connection circuits.
- Input video data received from the source 910 may be processed by the processor 940 based on one or more software programs stored in the memory 950, and may be processed by the processor 940 for the generation of output video provided to the display device 930.
- the software programs stored in the memory 950 may include a scalable video codec for performing the methods according to the present invention.
- the encoder or the codec may be stored in the memory 950, or may be read from a storage medium, such as Compact Disc (CD)-Read Only Memory (ROM) or a floppy disc or downloaded from a predetermined server through various networks.
- the encoder or the codec may be replaced with software programs or hardware circuits, or may be replaced with a combination of the software programs and the hardware circuits.
- the present invention can improve the performance of a codec using residual prediction or inter prediction.
- the present invention can improve a codec using intra-base prediction depending on a low-complicated decoding condition.
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Abstract
L'invention concerne un procédé et un appareil pour diminuer des artefacts de blocs dans un codage vidéo fondé sur des couches multiples. Un procédé de codage vidéo fondé sur des couches multiples consiste notamment à calculer une différence entre un bloc de prévision intermode pour le bloc d'une image de couche inférieure, qui correspond à un bloc arbitraire d'une image courante, et le bloc de l'image de la couche inférieure, à ajouter la différence calculée à un bloc de prévision intermode pour le bloc de l'image courante, à lisser un bloc, généré par l'addition, au moyen d'un filtre de lissage, et à coder une différence entre le bloc de l'image courante et un bloc généré par le lissage.
Applications Claiming Priority (3)
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US68908705P | 2005-06-10 | 2005-06-10 | |
KR1020050073835A KR100703788B1 (ko) | 2005-06-10 | 2005-08-11 | 스무딩 예측을 이용한 다계층 기반의 비디오 인코딩 방법,디코딩 방법, 비디오 인코더 및 비디오 디코더 |
PCT/KR2006/002205 WO2006132509A1 (fr) | 2005-06-10 | 2006-06-09 | Procede de codage video fonde sur des couches multiples, procede de decodage, codeur video, et decodeur video utilisant une prevision de lissage |
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EP1889487A1 true EP1889487A1 (fr) | 2008-02-20 |
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EP06768807A Withdrawn EP1889487A1 (fr) | 2005-06-10 | 2006-06-09 | Procede de codage video fonde sur des couches multiples, procede de decodage, codeur video, et decodeur video utilisant une prevision de lissage |
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EP (1) | EP1889487A1 (fr) |
WO (1) | WO2006132509A1 (fr) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
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KR100891662B1 (ko) | 2005-10-05 | 2009-04-02 | 엘지전자 주식회사 | 비디오 신호 디코딩 및 인코딩 방법 |
KR20070038396A (ko) | 2005-10-05 | 2007-04-10 | 엘지전자 주식회사 | 영상 신호의 인코딩 및 디코딩 방법 |
KR101365575B1 (ko) * | 2007-02-05 | 2014-02-25 | 삼성전자주식회사 | 인터 예측 부호화, 복호화 방법 및 장치 |
US20130329806A1 (en) * | 2012-06-08 | 2013-12-12 | Qualcomm Incorporated | Bi-layer texture prediction for video coding |
-
2006
- 2006-06-09 WO PCT/KR2006/002205 patent/WO2006132509A1/fr active Application Filing
- 2006-06-09 EP EP06768807A patent/EP1889487A1/fr not_active Withdrawn
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WO2006132509A1 (fr) | 2006-12-14 |
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