CN100586184C - Infra-frame prediction method - Google Patents
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Abstract
The invention relates to an intra-frame prediction method, comprising the following steps that: a 4x4 pixel luma block to be predicted is chosen to be as a current block; whether the current block is the center block is judged, if yes, energy functions of the residual error between prediction blocks of the current block and the current block in all predicting modes and a candidate predicting mode is determined according to the energy functions in different predicting modes, otherwise, a usable predicting mode is taken as the candidate predicting mode; a rate-distortion cost parameter in the candidate predicting mode is calculated, the candidate predicting mode with the minimal rate-distortion cost parameter is taken as the optimal predicting mode of the current block. The invention determines the candidate predicting mode according to the residual error energy function and determines the optimal predicting mode by calculating the rate-distortion cost parameter of the candidate predicting mode so as to decrease the number of the predicting modes which need to calculate the rate-distortion cost parameter, thereby reducing the amount of computation.
Description
Technical Field
The invention relates to an intra-frame prediction method, in particular to an intra-frame prediction method capable of effectively improving the operation speed.
Background
The new generation video coding standard H.264/AVC has good network performance, is suitable for interactive and non-interactive application environments, has received great attention since the self-release, and has the remarkable advantage of high compression efficiency. Fig. 1 shows a block diagram of the encoder framework of the h.264/AVC standard, whose working process can be divided into a forward channel and a reconstruction channel depending on the direction of the data stream. Current frame FnThe coding of (2) is to code the macro block of 16 × 16 pixels of the original image, the macro block coding is divided into intra-frame coding and inter-frame coding, and during the intra-frame coding and the inter-frame coding, the predicted macro block P is obtained by reconstructing the frame. In intra coding mode, P is decoded, reconstructed from coded macroblocks in the current frame, reconstructed macroblocks uF'nPrediction is derived, in inter-coded mode, P being derived from one or more reference frames F'n-1Exercising of the warpAnd obtaining a compensation prediction. Prediction macroblock P and current macroblock FnIs residual macroblock Dn，DnAfter transformation and quantization, a string of transformation parameters X is obtained, and the parameters X need to be processed in two aspects: firstly, reordering and entropy coding processing are carried out, and the whole process has no feedback component, so the process is called as a forward channel; second, inverse quantization and inverse transform processing, producing macroblock D'n，D′nAdding the prediction macro block P to obtain a reconstructed macro block uF'nReconstructing macroblock uF'nObtaining a reconstructed reference frame F 'through a series of processing'nFor motion estimation of the next frame and is therefore called reconstruction pass. The improvement of H.264/AVC performance is indistinguishable from some new techniques adopted by the H.264/AVC performance, such as adopting an intra-frame prediction method based on a spatial domain, adopting integer Discrete Cosine Transform (DCT) for transformation, adopting 4 x 4 pixel blocks for motion estimation/motion compensation, adopting loop filtering for a reconstruction channel, adopting a new entropy coding method and the like.
The intra-frame prediction based on a spatial domain is an important factor for improving the performance of H.264/AVC, the intra-frame prediction uses the spatial correlation of an image to predict the information of a current block according to the information of adjacent pixel blocks which are decoded and reconstructed to obtain a prediction block of the current block, then the residual errors of the current block and the prediction block of the current block are transformed, quantized and encoded, and in order to better represent the current block, the H.264/AVC adopts a Rate Distortion Optimization (RDO) technology to optimize the encoding quality and minimize the encoding bits.
In the h.264/AVC standard, each macroblock of 16 × 16 pixels is taken as a unit, and each macroblock includes a luminance block and two corresponding chrominance blocks, where the luminance block is 1 16 × 16 or 16 4 × 4, and the chrominance block is 8 × 8.
For a 4 × 4 luma block, there are 9 prediction modes for intra prediction, which are:
mode 0: vertical prediction (vertical prediction) mode
Mode 1: horizontal prediction (horizontal prediction) mode
Mode 2: DC prediction (DC prediction) mode
Mode 3: 45 degree directional prediction (diagonaldown/left prediction) mode
Mode 4: 135 degree directional prediction (diagonaldown/right prediction) mode
Mode 5: 112.5 degree Direction prediction (vertical-Right prediction) mode
Mode 6: 157.5 degree directional-prediction (horizontal-down prediction) mode
Mode 7: 67.5 degree directional prediction (vertical-left prediction) mode
Mode 8: 22.5 degree directional-up prediction (horizontal-up prediction) mode
In which the remaining 8 prediction modes, except for the DC prediction mode, are referred to as directional prediction modes, and fig. 2 shows a relationship diagram of a reference pixel and a current block pixel to be predicted, in which capital letters denote the reference pixel and lowercase letters denote the current block pixel. The numbers in fig. 3 indicate the orientation of the respective directional prediction modes.
For a 16 × 16 luma block, there are 4 prediction modes for intra prediction:
vertical prediction (vertical prediction) mode
Horizontal prediction (horizontal prediction) mode
DC prediction (DC prediction) mode
Plate prediction (plate prediction) mode
For an 8 × 8 chroma block, there are 4 prediction modes for intra prediction:
DC prediction (DC prediction) mode
Horizontal prediction (horizontal prediction) mode
Vertical prediction (vertical prediction) mode
Plate prediction (plate prediction) mode
From the above analysis it can be seen that: if M8 denotes the number of prediction modes for chroma blocks, M4 denotes the number of prediction modes for 4 × 4 luma blocks, and M16 denotes the number of prediction modes for 16 × 16 luma blocks, the number of combinations of luma and chroma block prediction modes in a macroblock is M8 × (M4 × 16+ M16) ═ 592, i.e., in order to determine the optimal mode for intra prediction for a macroblock, the encoder needs to perform 592 RDO calculations. Therefore, the improvement of the compression ratio of H.264/AVC is difficult to apply in real time at the cost of increased computational complexity.
Disclosure of Invention
The invention aims to provide an intra-frame prediction method aiming at the defects of the prior art, which is used for solving the problem of high calculation complexity of the conventional intra-frame prediction method, improving the speed of intra-frame prediction coding and being beneficial to the real-time application of an encoder.
The invention provides the following technical scheme through the embodiment:
an intra prediction method, comprising:
step 1: selecting a 4 x 4 pixel brightness block to be predicted as a current block;
step 2: judging whether the current block is a central block, if so, executing a step 3, otherwise, executing a step 4;
and step 3: calculating energy functions of residual errors of the prediction blocks of the current block and the current block in all prediction modes, determining candidate prediction modes according to the energy functions in different prediction modes, and executing the step 5;
wherein the step 3 specifically comprises:
step 31: calculating a prediction block of the current block in different prediction modes;
step 32: obtaining a prediction block of the current block and a residual error of the current block in different prediction modes according to the prediction block of the current block and the current block in different prediction modes;
step 33: performing discrete cosine transform on the residual errors in different prediction modes to obtain energy functions of the residual errors in different prediction modes;
wherein the calculation formula of the energy function is as follows:
wherein,
y is a width-direction coordinate of the current block, X is a height-direction coordinate of the current block, X is a residue between a prediction block of the current block and the current block, and DCT (y, X) is a DCT coefficient having coordinates (y, X) of the current block,
step 34: arranging energy functions of residuals under different prediction modes according to the sequence of energy values from small to large to sequentially obtain first energy, second energy, third energy and fourth energy with smaller energy values, and obtaining a first prediction mode corresponding to the first energy, a second prediction mode corresponding to the second energy, a third prediction mode corresponding to the third energy and a fourth prediction mode corresponding to the fourth energy;
step 35: determining candidate prediction modes according to the first energy, the second energy, the third energy and the fourth energy and the first prediction mode, the second prediction mode, the third prediction mode and the fourth prediction mode;
and 4, step 4: taking the available prediction modes as candidate prediction modes, and executing the step 5;
and 5: and calculating rate distortion cost parameters of the candidate prediction modes, and selecting the candidate prediction mode with the minimum rate distortion cost parameter as the optimal prediction mode of the current block.
According to the embodiment of the invention, the candidate prediction mode of the 4 multiplied by 4 pixel brightness block is selected according to the energy function, the optimal prediction mode is obtained by calculating the rate distortion cost parameters of the candidate prediction mode instead of obtaining the optimal prediction mode according to the rate distortion cost parameters of all the prediction modes, and due to the reduction of the number of the prediction modes, the calculation amount of the rate distortion cost parameters can be reduced, the operation speed is improved, and the method is suitable for real-time coding.
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FIG. 1 is a diagram of a prior art encoder framework of the H.264/AVC standard;
FIG. 2 is a diagram illustrating the relationship between a reference pixel and a current block pixel to be predicted in the prior art H.264/AVC standard;
FIG. 3 is a directional diagram of the directional prediction mode in the prior art H.264/AVC standard;
FIG. 4 is a flowchart of an embodiment of the intra prediction method of the present invention;
FIG. 5 is a flowchart illustrating an embodiment of an intra prediction method according to the present invention.
Detailed Description
The technical scheme of the invention is further explained by combining the drawings and the specific embodiment.
FIG. 4 is a flowchart of an embodiment of an intra prediction method according to the present invention, the intra prediction method comprises:
step 41: selecting a 4 x 4 pixel brightness block to be predicted as a current block;
step 42: judging whether the current block is a central block, if so, executing a step 43, otherwise, executing a step 44;
step 43: calculating energy functions of residual errors of the prediction blocks of the current block and the current block in all prediction modes, determining candidate prediction modes according to the energy functions in different prediction modes, and executing step 45;
step 44: step 45 is executed with the available prediction modes as candidate prediction modes;
step 45: and calculating rate distortion cost parameters of the candidate prediction modes, and selecting the candidate prediction mode with the minimum rate distortion cost parameter as the optimal prediction mode of the current block.
FIG. 5 is a flowchart of an embodiment of an intra prediction method according to the present invention, the intra prediction method comprises:
step 501: a 16 × 16 macroblock is divided into 16 4 × 4 luminance blocks, and step 502 is performed. The h.264/AVC standard is in units of macroblocks of 16 × 16 pixels, one macroblock includes one luminance block and two chrominance blocks, the luminance block is 1 16 × 16 or 16 4 × 4, the chrominance blocks are 8 × 8, and pixel values of a current luminance block or chrominance block are predictive-encoded in a plurality of prediction modes using pixel values that have been decoded and reconstructed by an upper block adjacent to the current block and an adjacent left block. Since the transform in the h.264/AVC standard is in units of 4 × 4 blocks, and the 4 × 4 blocks occupy a large proportion in the prediction coding, the present embodiment improves the prediction coding of the 4 × 4 luminance blocks, and the prediction coding method of the 16 × 16 luminance blocks and the 8 × 8 chrominance blocks is not changed.
Step 502: a 4 × 4 luma block to be predictively encoded is selected as the current block, and step 503 is performed. The prediction modes of the intra prediction method of the 4 × 4 luminance block include 8 directional predictions and 1 DC prediction. The selection of the prediction mode of the luminance block by using the RDO technique in the conventional h.264/AVC standard includes the following steps:
(1) for 4 × 4 luminance blocks, rate-distortion cost parameters under 9 prediction modes are respectively calculated, and the minimum value of the rate-distortion cost parameters and the prediction mode corresponding to the minimum value of the rate-distortion cost parameters are obtained. The rate-distortion cost parameter (RDCost) is calculated by the formula: RDCost ═ SSD + λ × bitrate, where RDCost is a rate-distortion cost parameter; SSD is the sum of squares of all elements of the difference block of the current block and the reconstructed block, i.e. the square of the reconstructed residual; λ is a function of Quantization Parameter (QP), λ 0.85 × 2(QP-12)/3(ii) a The bitrate is the code rate after entropy coding, i.e. the number of bits forming a code stream after predictive coding.
(2) The minimum rate-distortion cost parameters of 16 4 × 4 luminance blocks are obtained according to the above method, the 16 minimum rate-distortion cost parameters are added, and the sum after the addition is taken as the rate-distortion cost parameters of the 4 × 4 luminance blocks.
(3) For a 16 × 16 luma block, the sum of all elements after the hash transform of the residuals of the current block and the prediction block in 4 prediction modes, i.e., the residual hash transform Sum (STAD) value, is calculated, and the rate-distortion cost parameter of the prediction mode with the smallest STAD value is calculated as the rate-distortion cost parameter of the 16 × 16 luma block.
(4) And (3) comparing the rate distortion cost parameters obtained in the step (2) and the step (3), and selecting the prediction mode corresponding to the minimum rate distortion cost parameter as the prediction mode of the intra-frame brightness block.
As can be seen from the above formula of the rate-distortion cost parameter (1), each prediction mode of the current 4 × 4 luminance block needs to be pre-coded, the calculation complexity is high, in order to reduce the calculation complexity, the calculation of RDO may be simplified or the prediction modes used for calculating RDO may be reduced, in order to reduce the complexity of intra-frame coding while better maintaining the efficiency of intra-frame coding, the present embodiment adopts a method for reducing the prediction modes used for calculating RDO.
Step 503: and judging whether the current block is a central block, if so, executing the step 504, otherwise, executing the step 507. Since decoding reconstruction is performed in the order from left to right and from top to bottom in video encoding, if a left block adjacent to a current block and an adjacent upper block are both decoded, it is called that the left block and the upper block are available, when the left block is decoded and reconstructed, it is called that the left block is available, when the upper block is decoded and reconstructed, it is called that the upper block is available, and when both are not decoded, it is called that neither block is available. When the left block and the upper block are both available, the current block is the center block, and at the moment, 9 prediction modes are available corresponding to the current block; when the current block is not the center block, the prediction mode corresponding to the current block is referred to as an available prediction mode, and the available prediction modes are less than 9, and when only the left block is available, the available prediction modes are a horizontal prediction mode (mode 1), a DC prediction mode (mode 2), and a 22.5-degree direction prediction mode (mode 8), and when only the upper block is available, the available prediction modes are a vertical prediction mode (mode 0), a DC prediction mode (mode 2), a 45-degree direction prediction mode (mode 3), and a 67.5-degree direction prediction (mode 7).
Step 504: the energy function of the residuals of the current block and the prediction block in all prediction modes is calculated, and step 505 is executed. From the above analysis, if the current block is the center block, there are 9 prediction modes available, and in order to reduce the calculation amount of RDO calculation, a method of reducing the prediction modes is adopted. Since most areas of natural or synthetic images are composed of low frequencies, most high frequency information can be encoded with 0 runs, and high frequencies can roughly reflect the complexity of the texture of an image. In practical application, the information of the current block is predicted according to the texture direction of the current block by using the information of the decoded adjacent blocks, then the energy function is calculated for the corresponding residual error, the energy function defined by the invention is the mapping from a multidimensional frequency domain space to a one-dimensional energy space, the high-frequency component of the DCT of the texture residual error block reflects the detail information of the texture residual error, and in order to highlight the detail information of the texture residual error, the invention allocates higher weight (w (y, x)) for high frequency so as to amplify the influence of a high-frequency coefficient. By the definition of the DCT energy function described in the present invention, the more detailed the texture residual block (the more high frequency information), the larger its DCT energy. The invention uses the characteristic of energy function to select several modes with less complexity of texture residual block (less energy and less high frequency information) to calculate RDO, thereby reducing the number of modes for calculating RDO and finally realizing the purpose of accelerating the intra-frame coding speed. Wherein the calculation formula of the energy function is as follows:
here EDCTIs the energy calculation for the DCT transform of the prediction residual, ω and h are the width and height of the current block, DCT (y, x) is the DCT coefficient located at (y, x), and for a 4 × 4 luma block of h.264/AVC, the weight function w (y, x) (x ═ 1, 2.. h, y ═ 1, 2.. ω) in the above equation is defined as follows:
where ω is 4 and h is 4
The DCT transform in the above formula uses integer DCT transform in the standard, and the formula is as follows:
wherein, x is the residue of the current block and the prediction block.
Step 505: the energy function values of the reconstructed residuals under different prediction modes are arranged in the order from small to large, the minimum four energy values, namely, the first energy (E1), the second energy (E2), the third energy (E3), the fourth energy (E4), and the corresponding first prediction mode (m1), the second prediction mode (m2), the third prediction mode (m3), and the fourth prediction mode (m4) are selected, and step 506 is executed.
Step 506: candidate prediction modes are determined from the above four prediction modes m1, m2, m3 and m4 according to the screening principle described below, and step 508 is performed. The screening principle comprises the following steps:
step 5061: determining whether E2 is greater than α × E1, if so, executing step 5062; otherwise, step 5063 is performed.
Step 5062: the candidate prediction mode is m 1.
Step 5063: it is determined whether E3 is greater than α × E1, if so, go to step 5064, otherwise go to step 5065.
Step 5064: the candidate prediction modes are m1 and m 2.
Step 5065: it is determined whether E4 is greater than α × E1, if so, go to step 5066, otherwise go to step 5067.
Step 5066: the candidate prediction modes are m1, m2, and m 3.
Step 5067: it is determined whether E4 is less than β × E1, if so, go to step 5068, otherwise, go to step 5069.
Step 5068: the candidate prediction modes are m1 and m 2.
Step 5069: the candidate prediction modes are m1, m2, m3, and m 4.
The above α and β are constants, and the best coding effect is obtained by taking α as 1.4 and β as 1.05 through a large number of experiments.
Step 507: step 508 is performed with the available prediction modes as candidate prediction modes. When only the left block adjacent to the current block is available, the available prediction modes are mode 1, mode 2, mode 8; when only the upper block adjacent to the current block is available, the available prediction modes are mode 0, mode 2, mode 3, mode 7; when neither the left block nor the upper block adjacent to the current block is available, the candidate prediction mode is the DC prediction mode.
Step 508: RDO calculation is performed on each candidate prediction mode of the current block, the candidate prediction mode with the smallest rate-distortion cost parameter RDCost is selected as the optimal prediction mode of the current block, and step 509 is performed. When the adjacent left block and the adjacent upper block of the current block are available, RDO calculation is carried out according to the candidate prediction mode determined by the energy function, and the obtained candidate prediction mode with the minimum rate distortion cost parameter is the optimal prediction mode; when one of the adjacent left block or the adjacent upper block of the current block is available, performing RDO calculation on the available prediction mode, and taking the available prediction mode with the minimum rate-distortion cost parameter as the optimal prediction mode; and when the adjacent left block and the adjacent upper block of the current block are not available, the DC prediction mode is the optimal prediction mode.
Step 509: judging whether 16 luminance blocks are used as the current block to perform the above calculation, if so, executing step 510, otherwise, repeatedly executing step 502 until all 4 × 4 luminance blocks are predictive-coded.
Step 510: the minimum rate-distortion cost parameters of the 16 4 × 4 luminance blocks are added, and the added sum is taken as the rate-distortion cost parameter RDCost4 of the 4 × 4 luminance block, and step 512 is performed.
Step 511: rate distortion cost parameters of 4 prediction modes of the 16 × 16 luminance block are calculated to obtain a minimum rate distortion cost parameter and a prediction mode corresponding to the minimum rate distortion cost parameter, where the minimum rate distortion cost parameter is the rate distortion cost parameter RDCost16 of the 16 × 16 luminance block, and the prediction mode corresponding to the minimum rate distortion cost parameter is the optimal prediction mode of the 16 × 16 luminance block, and step 512 is executed.
Step 512: and comparing the rate-distortion cost parameter RDcost4 of the 4 × 4 luminance block with the rate-distortion cost parameter RDcost16 of the 16 × 16 luminance block, if RDcost4 is less than RDcost16, executing the step 513, otherwise, executing the step 514.
Step 513: the optimal prediction mode corresponding to each 4 × 4 luminance block is selected as the optimal prediction mode for the luminance block of the 16 × 16 macroblock.
Step 514: the optimal prediction mode of the 16 × 16 luminance block corresponding to RDcost16 is selected as the optimal prediction mode of the luminance block of the 16 × 16 macroblock.
In this embodiment, the intra prediction method of a 4 × 4 luminance block in the h.264/AVC standard is improved, the candidate prediction mode is determined by using an energy function obtained by DCT transform of a residual, RDO calculation is performed on the candidate prediction mode instead of RDO calculation performed on all prediction modes, and as the number of prediction modes for RDO calculation is reduced, the amount of RDO calculation can be effectively reduced, which is beneficial to application to real-time encoding.
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (5)
1. An intra prediction method, comprising:
step 1: selecting a 4 x 4 pixel brightness block to be predicted as a current block;
step 2: judging whether the current block is a central block, if so, executing a step 3, otherwise, executing a step 4;
and step 3: calculating energy functions of residual errors of the prediction blocks of the current block and the current block in all prediction modes, determining candidate prediction modes according to the energy functions in different prediction modes, and executing the step 5;
wherein the step 3 specifically comprises:
step 31: calculating a prediction block of the current block in different prediction modes;
step 32: obtaining a prediction block of the current block and a residual error of the current block in different prediction modes according to the prediction block of the current block and the current block in different prediction modes;
step 33: performing discrete cosine transform on the residual errors in different prediction modes to obtain energy functions of the residual errors in different prediction modes;
wherein the calculation formula of the energy function is as follows:
wherein,
y is a width-direction coordinate of the current block, x is a height-direction coordinate of the current block,x is a residual between a prediction block of the current block and the current block, DCT (y, X) is a DCT coefficient having coordinates (y, X) of the current block,
step 34: arranging energy functions of residuals under different prediction modes according to the sequence of energy values from small to large to sequentially obtain first energy, second energy, third energy and fourth energy with smaller energy values, and obtaining a first prediction mode corresponding to the first energy, a second prediction mode corresponding to the second energy, a third prediction mode corresponding to the third energy and a fourth prediction mode corresponding to the fourth energy;
step 35: determining candidate prediction modes according to the first energy, the second energy, the third energy and the fourth energy and the first prediction mode, the second prediction mode, the third prediction mode and the fourth prediction mode;
and 4, step 4: taking the available prediction modes as candidate prediction modes, and executing the step 5;
and 5: and calculating rate distortion cost parameters of the candidate prediction modes, and selecting the candidate prediction mode with the minimum rate distortion cost parameter as the optimal prediction mode of the current block.
2. The method according to claim 1, wherein the step 2 is specifically: and decoding the pixel brightness blocks from left to right and from top to bottom, wherein when the left pixel brightness block and the upper pixel brightness block which are adjacent to the current block are both decoded, the current block is a central block.
3. The method according to claim 1, wherein the step 35 specifically comprises:
step 351: judging whether the second energy is greater than 1.4 times of the first energy, if so, the first prediction mode is a candidate prediction mode, otherwise, executing step 352;
step 352: judging whether the third energy is greater than 1.4 times of the first energy, if so, the first prediction mode and the second prediction mode are candidate prediction modes, otherwise, executing a step 353;
step 353: judging whether the fourth energy is greater than 1.4 times of the first energy, if so, the first prediction mode, the second prediction mode and the third prediction mode are candidate prediction modes, otherwise, executing step 354;
step 354: and judging whether the fourth energy is less than 1.05 times of the first energy, if so, the first prediction mode and the second prediction mode are candidate prediction modes, and if not, the first prediction mode, the second prediction mode, the third prediction mode and the fourth prediction mode are candidate prediction modes.
4. The method according to claim 1, wherein the step 4 specifically comprises:
when an upper pixel luminance block adjacent to the current block has been decoded, taking a vertical prediction mode, a DC prediction mode, a 45-degree direction prediction mode, a 67.5-degree direction prediction mode as candidate prediction modes;
when a left pixel luminance block adjacent to the current block has been decoded, taking a horizontal prediction mode, a DC prediction mode, a 22.5 degree direction prediction mode as candidate prediction modes;
and when neither the upper pixel brightness block nor the left pixel brightness block adjacent to the current block is decoded, taking the DC prediction mode as a candidate prediction mode.
5. The method of claim 1, further comprising:
step 6: taking the sum of rate distortion cost parameters of the optimal prediction modes of the 16 4 × 4 pixel luminance blocks as the rate distortion cost parameter of the 4 × 4 pixel luminance blocks;
and 7: calculating residual Hasmard transform sum values of the 16 multiplied by 16 pixel luminance blocks under different prediction modes;
and 8: taking the rate distortion cost parameter of the prediction mode with the minimum residual Hasmaard transform sum value as the rate distortion cost parameter of the 16 multiplied by 16 pixel brightness block;
and step 9: and judging whether the rate distortion cost parameter of the 4 × 4 pixel brightness block is smaller than the rate distortion cost parameter of the 16 × 16 pixel brightness block, if so, taking the optimal prediction mode corresponding to the 4 × 4 pixel brightness block as the optimal prediction mode of the pixel brightness block, and if not, taking the optimal prediction mode corresponding to the 16 × 16 pixel brightness block as the optimal prediction mode of the pixel brightness block.
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| CN101873500B (en) * | 2009-04-24 | 2012-05-23 | 华为技术有限公司 | Interframe prediction encoding method, interframe prediction decoding method and equipment |
| CN101964906B (en) * | 2009-07-22 | 2012-07-04 | 北京工业大学 | Rapid intra-frame prediction method and device based on texture characteristics |
| CN102098507B (en) * | 2010-06-08 | 2013-12-25 | 同济大学 | Integrative compressing method and device of image |
| CN102281435B (en) * | 2010-06-11 | 2013-10-02 | 华为技术有限公司 | Encoding method, decoding method, encoding device, decoding device and encoding/decoding system |
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| CN101888549A (en) * | 2010-06-18 | 2010-11-17 | 浙江大学 | Intra-frame 4*4 forecasting model selection method based on transform domain information |
| CN101888549B (en) * | 2010-06-18 | 2012-05-02 | 浙江大学 | Intra-frame 4*4 forecasting model selection method based on transform domain information |
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