CN101527842B - Image processing method and image processing device for filtering blocking artifact - Google Patents
Image processing method and image processing device for filtering blocking artifact Download PDFInfo
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- CN101527842B CN101527842B CN 200810083152 CN200810083152A CN101527842B CN 101527842 B CN101527842 B CN 101527842B CN 200810083152 CN200810083152 CN 200810083152 CN 200810083152 A CN200810083152 A CN 200810083152A CN 101527842 B CN101527842 B CN 101527842B
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Abstract
The invention provides an image processing method for processing at least one image. The method comprises the following steps: detecting at least one edge in the image; selecting at least one first pixel and at least one second pixel according to the edge; determining whether the difference between the first pixel and the second pixel falls into a preset range so as to determine whether the edge has a blocking artifact; and filtering the detected blocking artifact.
Description
Technical field
The present invention relates to a kind of image processing method and device, relate in particular to a kind of edge that is used for judging image and whether be block effect, and image processing method and device that this block effect is filtered.
Background technology
In the technical field of image processing; MPEG (Moving Picture Experts Group) compress technique with (or) JPEG (Joint Photographic Experts Group) compress technique is applied on the related application such as coding and decoding, transmission, storage and broadcast of image in large quantities; In general, image in compression process can through discrete cosine transform (Discrete Cosine Transform, DCT) thereby can produce many problems simultaneously; For example; Because each DCT block (for example 8x8 block) all is individually to be encoded when compression, and does not consider the similitude between adjacent block, behind the image decoding that therefore will compress; Relatively poor quantification will cause the discontinuity (discontiunity) on the block border for conversion coefficient, is commonly referred to as block effect (block effect).
In the prior art, the relevant information that mainly when compressing, is provided through MPEG/JPEG, and then can the block effect in the image be removed; Yet the media that world today's epigraph is propagated is quite a lot of, makes original source video sequence often can not know; Therefore for the rear end of image processing, the getable compression relevant information of institute is also considerably less, under this situation; How can effectively the block effect in the image be removed, to be still the problem that needs solution and consider.
Summary of the invention
One of the object of the invention is to provide a kind of block effect of detected image, image processing method and device that also this block effect is filtered of being used for, to address the above problem.
The present invention discloses a kind of image processing method, is used to handle at least one image, comprising: detect at least one edge in this image; From this at least one edge, choose an edge; From this edge, select at least one first pixel and at least one second pixel; Whether whether the difference value of judging this first pixel and this second pixel falls in the preset range, be block effect to determine this edge; Filter detected this block effect; The sum of the present detected block effect of accumulative total; And when this sum is lower than pre-set threshold value, suspend the execution of the step of filtering detected this block effect.
The present invention also discloses a kind of image processing apparatus, is used to handle at least one image, comprising: edge detector is used for detecting at least one edge of this image; The block effect detector; Be coupled to this edge detector; Be used for choosing an edge, from this edge, select at least one first pixel and at least one second pixel from this at least one edge; Whether and whether the difference value of judging this first pixel and this second pixel fall in the preset range, be block effect to determine this edge; The block effect filter is coupled to this edge detector and this block effect detector, is used to filter detected this block effect; Counter is coupled to this block effect detector, is used for the sum of the detected block effect of accumulative total; And controller, be coupled to this counter and this block effect filter, be used for when this sum is lower than pre-set threshold value, this block effect filter is temporarily invalid.
Description of drawings
Fig. 1 is the function block schematic diagram of the embodiment of image processing apparatus of the present invention;
Fig. 2 is the flow chart of the embodiment of image processing method of the present invention;
Fig. 3 is the continuity flow chart of corresponding diagram 2.
The primary clustering symbol description
101 image processing apparatus
102 edge detectors
103 block effect detectors
104 block effect filters
105 counters
106 registers
107 controllers
Embodiment
See also Fig. 1, it is the function block schematic diagram of the embodiment of image processing apparatus 101 of the present invention.Image processing apparatus 101 can be used to handle a plurality of images; And the digital picture (digital image) of the alleged image of the present invention for being constituted by a plurality of pixels (pixel), and these pixel values can be R, G or the B pixel value in the rgb format or can be brightness value or the chroma value in the yuv format or be the numerical value of the display characteristic of any represent pixel in other common video specification.As shown in the figure; Image processing apparatus 101 comprises edge detector (edge detector) 102, block effect detector (block effectdetector) 103, block effect filter (block effect filter) 104, counter (counter) 105, register (recorder) 106 and controller (controller) 107, and wherein block effect detector 103 is coupled to edge detector 102; Block effect filter 104 is coupled to edge detector 102 and block effect detector 103; Counter 105 is coupled to block effect detector 103; Register 106 is coupled to block effect detector 103; And controller 107 is coupled to block effect detector 103, block effect filter 104, counter 105 and register 106.
Please consult Fig. 2 and Fig. 3 simultaneously, Fig. 2 is the flow chart of the embodiment of image processing method of the present invention, and Fig. 3 is the continuity flow chart of corresponding diagram 2.As shown in the figure, image processing apparatus 101 performed image processing methods shown in Figure 1 may further comprise the steps:
Step 502: a plurality of edges in the detected image;
Step 504: from these edges, choose an edge and handle;
Step 506: from this edge; Determine image block, and from this image block, select at least one neighbor of at least one pixel and this pixel; Does and the value differences of calculating between this pixel and this neighbor fall in the preset range? If; Then continue next procedure 508, otherwise, skip to step 520;
Step 508: judge that this edge is a block effect;
Step 510: the sum of present detected block effect is added increment value (for example 1);
Step 512: the position of writing down this block effect;
Step 514: judge that difference between the position of position and last block effect of this block effect equals another difference between the position of position and the first two block effect of this last block effect? If; Then continue next procedure 516; Otherwise, skip to step 520 (that is skip over step 516 and 518 do not carry out);
Step 516: check in another image on the position corresponding to this block effect of this image to have another block effect? If, then continue next procedure 518, otherwise, skip to step 520 (that is skip over step 518 do not carry out);
Step 518: filter this block effect;
Step 520: judge whether to handle all edges in this image? If, then continue next procedure 524, otherwise, another step 522 continued;
Step 522:, get back to step 506 then so that this next one edge is handled by selecting next edge in these edges;
Is step 524: the sum of judging present all block effects that add up lower than pre-set threshold value? If, then continue next procedure 526, otherwise, another step 528 continued;
Step 526: when handling next and open image, step 514,516 and 518 skipped over and do not carry out;
Step 528: when handling next image, still need execution in step 514,516 and 518;
Step 530: judged whether that next image needs to handle? If then continue next procedure 532, otherwise this flow process finishes; And
Step 532: at present the sum of all block effects resets to initial value (for example 0), gets back to step 502 then so that next image is handled.
Below begin to explain the details of the image processing method of image processing apparatus 101 execution graphs 2 and 3.At first; In edge detector 102 detected image a plurality of edges (edge) (step 502); In general; Suo Beier filter (Sobel filter) is the filter that two kinds of common can be used to detect the edge with Laplace filter (Laplace filter), because its function is known in the art with running, does not therefore detail in addition; Then, block effect detector 103 can select the edge to handle (step 504) from these edges; Then, block effect detector 103 judges whether the value differences between near at least one neighbor of at least one pixel and this pixel this edge falls into preset range interior (step 506), according to embodiment; This pixel chooses from the one side at this edge; This neighbor is come out by the pixel selection that the another side at this edge chooses or goes up on the edge of, and in addition, common edge has two kinds usually in the image: first kind is the edge of real-world object (real edge); The edge of object in the image just; Second kind of edge that produces for block effect, after edge detector 102 decision edges, can be further relatively the adjacent pixels value difference of this both sides of edges is different and to judge this edge be the edge that belongs to which kind of form by block effect detector 103; In general; If value differences then can be judged the edge that this edge is a real-world object greater than first value, and if value differences during less than this first value and greater than second value (it is interior just to fall into preset range of the present invention); Then can judge this edge is block effect; Note that those skilled in the art as long as after understanding above-mentioned principle, just have the ability to determine the first suitable value, second value and corresponding preset range according to practical situation (for example experiment experience value).
If in step 506, judge and learn that this value differences falls in the preset range, then this edge of block effect detector 103 decidables is a block effect (step 508); Then; Counter 105 can add 1 (step 510) with the sum of present detected block effect; And register 106 can these block effects of record position (step 512), controller 107 can judge whether difference between the position of position and last block effect of this block effect equals another difference (step 514) between the position of position and the first two block effect of this last block effect then; Please note; In other embodiment; Whether controller 107 also can be judged promptly also whether the appearance position of these block effects has certain regularity, and reached the identical effect of step 514 via the position of judging a plurality of block effects that occur successively continuously and fixed interval numerical value (for example 8); Next; Learn that these differences equate really if in step 514, judge; Then block effect detector 103 will check in another image on the position corresponding to this block effect of this image whether exist another block effect (step 516); In this embodiment, this another image is a last image of this image on the time shaft; Again; If there is this another block effect in this another image really; Then block effect filter 104 can carry out low pass (low pass) Filtering Processing to filter this block effect (step 518) to this edge; In general, median (median) Filtering Processing is a kind of common low-pass filtering treatment just; On the other hand, if there is not this another block effect in this another image, then controller 107 can controlled area block effect filtering device 104 temporarily invalid (disabled), and like this, step 518 will be skipped over not to be carried out and make flow process skip to step 520; Moreover; If in step 514, judge and learn that these differences are unequal; Then controller 107 is also can controlled area block effect filtering device 104 temporarily invalid, and like this, step 518 will be skipped over and not carry out; And need not carry out the inspection work of step 516 this moment yet, thereby flow process can jump directly to step 520.
Please note; Image processing apparatus 101 of the present invention can be handled two images simultaneously; Perhaps earlier with this another image storage of step 516 indication in frame buffer (image buffer) for subsequent treatment; And in fact should adopt which kind of mode comparatively favourable, the processing frequency range that depends on image processing apparatus 101 is with operational capability; In addition; Whether step 516 identifies the appearance position of block effect on the time shaft consistent; Therefore this another image can be second image in last image, front of this image on the time shaft or arbitrary image of front; And in other embodiments, this another image more can be arbitrary image of a back image, second image in back or the back of this image on the time shaft; Moreover whether controller 107 also can come the position of block effect on the judgement time axle consistent with reference to 3 of different time points (or more than) images.
On the other hand, if judgement learns that this value differences does not fall in this preset range in step 506, then can skip to step 520, at this moment, block effect detector 103 will judge whether to have handled all edges (step 520) in this image.
If judgement is learnt and do not handled all edges in step 520, then block effect detector 103 will then be got back to step 506 so that this next one edge is handled by choosing still untreated next edge (step 522) in these edges.
On the other hand, if judgement learns that all edges all dispose in step 520, controller 107 will judge whether the sum of present all block effects that add up is lower than pre-set threshold value (threshold) (step 524); If this moment, the sum of block effect was lower than pre-set threshold value really; The previous detected block effect of expression is not real block effect; Then controller 107 is can controlled area block effect filtering devices 104 temporarily invalid, like this, handles can skip over step 518 when next opens image and do not carry out when image processing apparatus 101; And need not carry out the judgment task of step 514 and the inspection work of step 516 this moment yet; Therefore handle can step 514,516 and 518 all be skipped over when next opens image when image processing apparatus 101 and do not carry out (step 526), like this, just can avoid the operation of block effect elimination improperly and cause the image quality deterioration; Note that those skilled in the art as long as after understanding above-mentioned principle, just have the ability to determine suitable pre-set threshold value according to practical situation (for example experiment experience value); On the other hand; If this moment block effect sum and be not less than pre-set threshold value; Then controller 107 can be kept block effect filter 104 effective (enabled), like this, and meeting execution in step 518 when image processing apparatus 101 is handled next image; And step 514 and 516 also need recover to carry out (step 528).
In this embodiment; Controller 107 is after all edges all dispose in each image; Whether the sum of just judging present all block effects that add up is lower than this pre-set threshold value, yet should not be used as restriction of the present invention with this, further; Controller 107 also can come the sum to block effect to carry out judgment task At All Other Times, judges after for example can at least 10 edge treated finish in each image.
At last, image processing apparatus 101 will judge whether that next image needs to handle (step 530); Learn do not have other image to need to handle if judge; Then whole flow process so far finishes; On the other hand; Still have other image to need to handle if judgement is learnt, then counter 105 can reset to 0 (step 532) with the sum of present all block effects, gets back to step 502 then so that next image is handled.
Image processing method of the present invention and device can filter block effect and the definition of increase image; And the information when not needing MPEG or JPEG compression fully and decompressing; Also need not utilize the preceding image of original, uncompressed; Therefore; No matter image has not through overcompression, also no matter image whether through amplifying (for example the 8x8 block is enlarged into the 16x16 block), dwindling (for example the 16x16 block is reduced into the 8x8 block) or translation (shift), can detect block effect via embodiment of the present invention and filter.
Please note; Technology described in the embodiments of the invention and principle can be applicable in the various image processing apparatus; For example still image processing unit (like digital camera) or dynamic video the system (like LCD) (Liquid Crystal Display; LCD), LCD TV (LCD TV) or DTV (digital TV) etc.; Those skilled in the art just have the ability to apply the present invention in the middle of other similar technical field as long as after the mode of operation of understanding disclosed embodiment of this invention and principle.
In addition; Any personnel that are familiar with design of electronic circuits, Digital Signal Processing or Digital Image Processing can realize above-mentioned image processing method and device according to various hardware circuit design or software program editor's principle after the operating principle of understanding the embodiment of the invention.
The above is merely the preferred embodiments of the present invention, and any equivalence that application requires the scope of protection to make according to the present invention changes and revises, and all should belong to covering scope of the present invention.
Claims (16)
1. an image processing method is used to handle image, comprising:
Detect at least one edge in this image;
From this at least one edge, choose an edge;
From this edge, select at least one first pixel and at least one second pixel;
Whether whether the difference value of judging this first pixel and this second pixel falls in the preset range, be block effect to determine this edge;
Filter detected this block effect;
The sum of the present detected block effect of accumulative total; And
When this sum is lower than pre-set threshold value, suspend the execution of the step of filtering detected this block effect.
2. image processing method as claimed in claim 1, the step that wherein detects at least one edge in this image detects a plurality of edges in this image, and this image processing method also comprises:
Write down the position of a plurality of block effects; And
Come the execution of the step of detected this block effect of controlled filter according to the position of these block effects.
3. image processing method as claimed in claim 2, wherein come the step of execution of the step of detected this block effect of controlled filter to comprise according to the position of these block effects:
Judge first difference between the position of position and last block effect of present block effect, whether equal second difference between the position of position and the first two block effect of this last block effect; And
If this first difference and this second difference are unequal, then suspend the execution of the step of filtering detected this block effect.
4. image processing method as claimed in claim 3 is used to handle a plurality of images, and this image processing method also comprises:
If this first difference equates with this second difference, then check in another image on the position corresponding to this block effect of this image whether have another block effect; And
If there is not this another block effect, then suspend the execution of the step of filtering detected this block effect.
5. image processing method as claimed in claim 4, wherein this another image is a last image of this image on the time shaft.
6. image processing method as claimed in claim 1, wherein this preset range is between first critical value and second critical value, and this first critical value is greater than this second critical value.
7. image processing method as claimed in claim 6, wherein, if this difference value between this first critical value and this second critical value, judges then that this edge is a block effect.
8. image processing method as claimed in claim 6 wherein, is the target edges in this image if this difference value, is then judged this edge greater than this first critical value.
9. an image processing apparatus is used to handle at least one image, comprising:
Edge detector is used for detecting at least one edge of this image;
The block effect detector; Be coupled to this edge detector; Be used for choosing an edge, from this edge, select at least one first pixel and at least one second pixel from this at least one edge; Whether and whether the difference value of judging this first pixel and this second pixel fall in the preset range, be block effect to determine this edge;
The block effect filter is coupled to this edge detector and this block effect detector, is used to filter detected this block effect;
Counter is coupled to this block effect detector, is used for the sum of the detected block effect of accumulative total; And
Controller is coupled to this counter and this block effect filter, is used for when this sum is lower than pre-set threshold value, and this block effect filter is temporarily invalid.
10. image processing apparatus as claimed in claim 9, wherein this edge detector detects a plurality of edges in this image, and this block effect detector is judged near the block effect that whether exists at each edge in these edges.
11. image processing apparatus as claimed in claim 9, wherein this edge detector detects a plurality of edges in this image, and this block effect detector judges whether these edges exist block effect, and this image processing apparatus also comprises:
Register is coupled to this block effect detector, the position that is used to write down a plurality of block effects,
Wherein, this controller also is coupled to this register, is used for controlling this block effect filter according to the position of these block effects.
12. image processing apparatus as claimed in claim 11; Wherein this controller is judged first difference between the position of position and last block effect of present block effect; Whether equal second difference between the position of position and the first two block effect of this last block effect; If this first difference and this second difference are unequal, then this controller is temporarily invalid with this block effect filter.
13. image processing apparatus as claimed in claim 12; Be used to handle a plurality of images; If this first difference equates with this second difference; Then this block effect detector also checks in another image on the position corresponding to this block effect of this image whether have another block effect, and wherein this controller is checked out when not having this another block effect in this another image at this block effect detector, and this block effect filter is temporarily invalid.
14. image processing apparatus as claimed in claim 13, wherein this another image is a last image of this image on the time shaft.
15. image processing method as claimed in claim 9, wherein this preset range is between first critical value and second critical value, and this first critical value is greater than this second critical value.
16. image processing method as claimed in claim 15, wherein, if this difference value between this first critical value and this second critical value, judges then that this edge is a block effect.
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US8542751B2 (en) * | 2010-08-20 | 2013-09-24 | Intel Corporation | Techniques for identifying and reducing block artifacts |
US20140254938A1 (en) * | 2011-11-24 | 2014-09-11 | Thomson Licensing | Methods and apparatus for an artifact detection scheme based on image content |
CN104239909B (en) * | 2014-08-11 | 2018-03-16 | 北京捷通华声语音技术有限公司 | A kind of recognition methods of image and device |
CN104361312B (en) * | 2014-10-16 | 2017-11-14 | 北京捷通华声语音技术有限公司 | A kind of method and apparatus that character recognition is carried out to image |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5881180A (en) * | 1996-02-08 | 1999-03-09 | Sony Corporation | Method and apparatus for the reduction of blocking effects in images |
CN1668106A (en) * | 2004-03-09 | 2005-09-14 | 扬智科技股份有限公司 | Method and apparatus for removing blocking effect of image frame using loop filter |
CN1694537A (en) * | 2004-04-29 | 2005-11-09 | 联发科技股份有限公司 | Adaptive de-blocking filtering apparatus and method for MPEG video decoder |
CN1988663A (en) * | 2005-12-21 | 2007-06-27 | 株式会社东芝 | Image processing apparatus, control method, and program |
-
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- 2008-03-07 CN CN 200810083152 patent/CN101527842B/en active Active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5881180A (en) * | 1996-02-08 | 1999-03-09 | Sony Corporation | Method and apparatus for the reduction of blocking effects in images |
CN1668106A (en) * | 2004-03-09 | 2005-09-14 | 扬智科技股份有限公司 | Method and apparatus for removing blocking effect of image frame using loop filter |
CN1694537A (en) * | 2004-04-29 | 2005-11-09 | 联发科技股份有限公司 | Adaptive de-blocking filtering apparatus and method for MPEG video decoder |
CN1988663A (en) * | 2005-12-21 | 2007-06-27 | 株式会社东芝 | Image processing apparatus, control method, and program |
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