KR20140059270A - Method and apparatus for multiple pass video coding and decoding - Google Patents

Abstract

A video encoder, a video decoder and a corresponding method for encoding and decoding video signal data using a multipath video encoding technique are provided. The video encoder includes a motion estimator 116 and a decomposition module 174. The motion estimator performs motion estimation on the video signal data to obtain motion residual corresponding to the video signal data in the first encoding path. The decomposition module in signal communication with the motion estimator decomposes motion residue in the subsequent encoding path.

Description

[0001] METHOD AND APPARATUS FOR MULTIPLE PASS VIDEO CODING AND DECODING [0002]

This application claims priority from PCT International Application No. PCT / US2006 / 037139 entitled "Method and Apparatus for Multipath Video Coding and Decoding," filed September 22, 2006, which is hereby incorporated by reference in its entirety Claim priority.

The present invention relates generally to video encoding and decoding, and more particularly to a method and apparatus for multi-path video encoding and decoding.

Part 10: Advanced Video Coding (AVC) standards / International Telecommunication Standardization / International Electrotechnical Commission (ISO / IEC) MPEG-4 (Moving Picture Experts Group-4) The H.264 standard (hereinafter "MPEG4 / H.264 standard" or simply "H.264 standard") is currently the most powerful and state-of-the-art video coding standard . Like all other video coding standards, the H.264 standard uses block-based motion compensation and discrete cosine transform (DCT) -type conversion coding. It is well known that DCT is efficient for video coding and is suitable for high performance applications such as high definition television (HDTV). However, the DCT algorithm is not suitable for applications requiring very low bit rates, such as dedicated video cell phones. At a very low bit rate, the DCT transform will result in blocking artifacts, even if a deblocking filter is used, which means that there are few coefficients that can be coded at a very low bit rate, This is because there is a tendency to have a wide quantization step.

Matching Pursuit (MP) is a greedy algorithm that decomposes an arbitrary signal into a linear extension of selected waveforms from a redundant dictionary of functions. These waveforms are selected to optimally match the signal structure.

Suppose we have a 1-D signal f (t) and want to decompose this signal using a basis vector from an over-complete dictionary set G.

Here,? Is an indexing parameter associated with a particular dictionary element. Decomposition begins by selecting γ to maximize the absolute value of the inner product as follows:

The residual signal is then calculated as:

This residual signal is then expanded in the same manner as the original signal. The procedure is repeated until a set number of expansion coefficients is generated or until a predetermined energy threshold for the remainder is reached. Each step n produces a pre-function γ _n . After the entire M step, the signal can be approximated by a linear function of dictionary elements as follows:

The complexity of MP decomposition of the signal of n samples is proved to be in the order k N n d n nlog ₂ n. Where d depends on the size of the dictionary without considering the translation, N is the number of selected expansion coefficients, and the constant k follows the strategy for selecting the dictionary function. Given a high overcomplete dictionary, the MP requires more computation than the 8x8 and 4x4 DCT integer transformations used in the H.264 standard, whose complexity is defined as o (nlog ₂ n).

In general, the MP algorithm is suitable for any set of residual base forms. It has been proposed to extend the signal using the overcomplete basis of the Gabor function. The 2-D gauge dictionary is very redundant, and each shape can be at any integer-pixel location in the coded residual picture. The frame-based Gabor dictionary does not have an artificial block structure because MP has a much larger dictionary set and each coded basis function is well matched to the structure of the residual signal.

The redundant dictionary set is used for the proposed video coding system using the MP algorithm (hereinafter referred to as "prior art Gabor based MP video coding approach") for very low bit rate video coding based on MP Has been adapted. The proposed system is based on a simulation model for very low bit rate picture coding, or a framework of a hybrid bit rate hybrid DCT system, simply referred to as "SIM3 ", where the DCT residual coders are replaced by MP coders do. The coder uses MP to decompose the motion residual image with pre-separable 2-D Garber functions. This proposed system appears to operate well at low bit rate low motion sequences.

A smooth 16x16 sine-square window was applied to a predictive picture for 8x8 partitions of the Gabor-based MP video coding approach of the prior art. The MP video codec of the prior art Gabor-based MP video coding approach is based on the ITU-T H.263 codec. However, the H.264 standard enables variable block-size motion compensation of small block sizes that can be as small as 4x4 for luma motion compensation. In addition, the H.264 standard is based primarily on the 4x4 DCT type conversion, not the 8x8 as in most other significant conventional video coding standards, for the baseline and main profile. Directional spatial prediction for intra coding improves the quality of the prediction signal. All these important design features make the H.264 standard more effective, but it requires that more complex situations be handled when applying MP to the H.264 standard. The smooth 16x16 sine window is expressed as:

A hybrid coding scheme (hereinafter "prior art hybrid coding scheme") has been proposed that benefits from some of the features introduced by the H.264 standard for motion compensation and replaces the transformation in the spatial domain. The prediction error is coded using the MP algorithm, which decomposes the signal into a suitably designed two-dimensional anisotropic redundant dictionary. In addition, fast atomic search technology was introduced. However, the proposed prior art hybrid coding technique does not describe whether a 1-pass or 2-pass technique is used. Further, although the proposed prior art hybrid coding technique has disclosed that the motion compensation section conforms to the H.264 standard, it is possible to determine whether any deblocking filter is used in the coding technique, It does not describe whether any other methods are used to smooth the blocking artifacts.

These and other drawbacks and drawbacks of the prior art are addressed by the present invention relating to a method and apparatus for multi-path video encoding and decoding.

According to one aspect of the present invention, a video encoder is provided for encoding video signal data using a multipath video encoding technique. The video encoder includes a motion estimator and a decomposition module. The motion estimator performs motion estimation on the video signal data to obtain a motion residual corresponding to the video signal data in the first encoding path. The decomposition module in signal communication with the motion estimator decomposes motion residue in the subsequent encoding path.

According to another aspect of the present invention, a method of encoding video signal data using a multipath video encoding technique is provided. The method includes performing motion estimation on the video signal data to obtain motion residue corresponding to video signal data in a first encoding path and decomposing motion residuals in a subsequent encoding path.

According to still another aspect of the present invention, there is provided a video decoder for decoding a video bitstream. The video decoder includes an entropy decoder, an atom decoder, an inverse transformer, a motion compensator, a deblocking filter, and a synthesizer. The entropy decoder decodes the video bit stream to obtain a decomposed video bit stream. An atomic decoder in signal communication with an entropy decoder decodes decomposed atoms corresponding to the decomposed bitstream to obtain decoded atoms. An inverse converter in signal communication with the atom decoder applies an inverse transform to the decoded atoms to form the reproduced residual image. The motion compensator for signal communication with the entropy decoder performs motion compensation using a motion vector corresponding to the decomposed bitstream to form a reproduced predictive image. A deblocking filter in signal communication with the motion compensator performs deblocking filtering on the reproduced predictive image to smooth the reproduced predictive image. The synthesizer that is in signal communication with the inverse transformer and the superposed block motion compensator synthesizes the reproduced predicted image and the residual image to obtain the reproduced image.

According to still another aspect of the present invention, a method of decoding a video bitstream is provided. The method includes decoding a video bit stream to obtain a decomposed video bit stream, decoding the decomposed atom corresponding to the decomposed bit stream to obtain a decoded atom, applying the inverse transform to the decoded atom, Forming a reconstructed predictive image by performing motion compensation using a motion vector corresponding to the decomposed bitstream, performing deblocking filtering on the reproduced predictive image to smooth the reproduced predictive image And synthesizing the reproduced predictive image and the residual image to obtain a reproduced image.

These and other aspects, features, and advantages of the present invention will become apparent from the following detailed description of illustrative embodiments which will be described in connection with the accompanying drawings.

The present invention will be better understood with reference to the following exemplary drawings.
1A and 1B illustrate an exemplary first and second path section of an encoder of an MP encoder / decoder (CODEC) based on a dual path H.264 standard, in which the principles of the present invention may be applied according to an embodiment of the present invention. Fig.
2 is a drawing of an exemplary decoder of an MP encoder / decoder (CODEC) based on a dual-path H.264 standard, to which the principles of the present invention may be applied in accordance with an embodiment of the present invention.
3 is a diagram of an exemplary method for encoding an input video sequence in accordance with an embodiment of the invention.
4 is a diagram of an exemplary method for decoding an input video sequence in accordance with an embodiment of the present invention.

The present invention relates to a method and apparatus for multi-path video encoding and decoding. Advantageously, the present invention corrects blocking artifacts introduced by, for example, the DCT transform employed in the H.264 standard, in very low bit rate applications. It will also be appreciated that the present invention is not limited to low bit rate applications and may be used for other (higher) bit rates while maintaining the scope of the present invention.

The description sets forth the principles of the invention. Accordingly, those skilled in the art will be able to devise various arrangements which, although not explicitly described or shown herein, embody the principles of the invention and are included in its spirit and scope.

All examples and conditional language referred to herein are intended for pedagogical purposes to assist the reader in understanding the principles and concepts of the present invention provided by the inventor and to enhance the skill, And the like.

Furthermore, all statements herein reciting principles, aspects and embodiments of the invention, as well as specific examples of the invention, are intended to encompass both structural and functional equivalents thereof. It is also intended that such equivalents include all currently known equivalents as well as any equivalents developed in the future, i. E., Any elements developed to perform the same function regardless of structure.

Thus, for example, those skilled in the art will appreciate that the block diagrams presented herein represent conceptual views of illustrative circuitry embodying the invention. Likewise, any flowchart, flowchart, state transition, pseudo code, etc., may be represented as substantially computer-readable media, whether or not a computer or processor is clearly shown, And the like.

The functionality of the various components shown in the figures may be provided through use of dedicated hardware as well as hardware capable of executing the software in combination with appropriate software. When provided by a processor, the functions may be provided by a single dedicated processor, a single shared processor, or a plurality of individual processors, some of which may be shared. Also, the explicit use of the term "processor" or "controller" should not be construed to refer exclusively to hardware capable of executing software, only memory, random access memory (RAM), and non-volatile storage devices.

Other hardware, tolerances and / or orders may also be included. Likewise, any of the switches shown in the figures are merely conceptual. These functions may be performed through the operation of program logic, through dedicated logic, through program control and the interaction of dedicated logic, or manually, and the specific techniques may be implemented in a manner that is more clearly understood from the context It is selectable by the person.

In the claims hereof, any component that is indicated as a means for performing a particular function may be, for example, a) a combination of circuit elements that perform the function, or b) an appropriate circuit Is intended to encompass any means of performing the function, including any form of software, including, but not limited to, firmware, microcode, and the like. The invention as defined by these claims is based on the fact that the functionality provided by the various cited means is obtained by combining together in the manner claimed. Thus, any means capable of providing such functionality are considered to be the same as those shown herein.

In accordance with the principles of the present invention, a multipath video encoding and decoding technique is provided. For multipath video encoding and decoding techniques, matching tracking (MP) may be used. In an exemplary embodiment, a dual path H.264 based coding scheme is disclosed for MP video coding.

The H.264 standard applies block-based motion compensation and DCT transforms similar to other video compression standards. At a very low bit rate, the DCT transform will result in blocking artifacts even if a deblocking filter is used, which means that there are few coefficients that can be coded at a very low bit rate and that each coefficient has a very wide quantization step This is because. In accordance with the principles of the present invention, an MP using an overcomplete basis is adapted to code the residual image. The motion compensation and mode decision section conforms to the H.264 standard. Overlapped block motion compensation (OBMC) is applied to smooth the predicted image. In addition, a new approach is provided to select a base other than MP.

In accordance with the principles of the present invention, the video encoder and / or decoder applies OBMC to the predicted image to reduce blocking artifacts caused by the predictive model. The MP algorithm is used to code the residual image. The advantage of MP is that it is frame-based rather than block-based, so there is no blocking artifact caused by the coding residual difference.

1A and 1B, exemplary first and second path portions of an encoder of an MP encoder / decoder (CODEC) based on a dual path H.264 standard are generally indicated by reference numerals 110 and 160. The encoder is generally denoted by reference numeral 190, and the decoder section is generally denoted by reference numeral 191.

1A, an input of a first path portion 110 is connected in signal communication with a non-inverting input of a combiner 112, an input of an encoder control module 114, and a first input of a motion estimator 116 . The first output of the combiner 112 is connected in signal communication with the first input of the buffer 118. The second output of the combiner 112 is connected in signal communication with the input of the integer conversion / scaling / quantization module 120. The output of the integer transform / resize / quantize module 120 is connected in signal communication with the first input of the resize / inverse transform module 122.

The first output of the encoder control module 114 is connected in signal communication with the first input of the intra frame predictor 126. The second output of the encoder control module 114 is connected in signal communication with the first input of the motion compensator 124. A third output of the encoder control module 114 is connected in signal communication with a second input of the motion estimator 116. The fourth output of encoder control module 114 is connected in signal communication with a second input of scaling / inverse transform module 122. The fifth output of the encoder control module 114 is connected in signal communication with the first input of the buffer 118.

The output of motion estimator 116 is connected in signal communication with a second input of motion compensator 124 and a second input of buffer 128. The inverting input of the combiner 112 is selectively connected to the output of the motion compensator 124 or the output of the intra frame predictor 126 in signal communication. The output of the selected one of the motion compensator 124 or the intra frame predictor 126 is connected in signal communication with the first input of the synthesizer 128. The output of the resizing / inverse transforming module 122 is connected in signal communication with the second input of the combiner 128. The output of the combiner 128 is connected in signal communication with the second input of the intra frame predictor 126, the third input of the motion estimator 116, and the inputs / outputs of the motion compensator 124. The output of the buffer 118 is available as an output of the first path section 110.

In the first path portion 110, the encoder control module 114, the integer transform / resize / quantization module 120, the buffer 118, and the motion estimator 116 are included in the encoder 190. In addition, in the first path portion, the resizing / inverse transforming module 122, the intra-frame predictor 126, and the motion compensator 124 are included in the decoder unit 191.

The input of the first path unit 110 receives the input video 111 and outputs control data (e.g., a motion vector, a mode selection, a predictive image, etc.) for use in the second path unit 160, (118).

Referring to FIG. 1B, the first input of the second path unit 160 is connected in signal communication with the input of the entropy coder 166. This first input receives control data 162 (e.g., mode selection, etc.) and motion vector 164 from first path section 110. The second input of the second path portion 160 is connected in signal communication with the non-inverting input of the combiner 168. A third input of the second path unit 160 is connected in signal communication with the input of the overlap block motion compensation (OBMC) / deblocking module 170. A second input of the second path section 160 receives the input video 111 and a third input of the second path section receives the predicted image 187 from the first path section 110.

The output of the combiner 168, which provides the residue 172, is connected in signal communication with the input of an atom finder 174. The output of the atomic finder 174 providing the coded residue 178 is connected in signal communication with the input of the atomic coder 176 and the first non-inverting input of the combiner 180. The output of the OBMC / deblocking module 170 is connected in signal communication with the inverting input of the combiner 168 and the second noninverting input of the combiner 180. The output of the combiner 180, which provides the output video, is connected in signal communication with the input of the reference buffer 182. The output of the atomic coder 176 is connected in signal communication with the input of the entropy coder 166. The output of the entropy coder 166 is available as an output of the second path unit 160 and provides an output bit stream.

In the second path section 160, the entropy coder is included in the encoder 190 and includes a combiner 168, an OBMC module 170, an atom finder 174, an atom coder 176, and a reference buffer 182, Is included in the decoder unit 191.

Referring to FIG. 2, an exemplary decoder of a MP encoder / decoder (CODEC) based on a dual path H.264 standard is generally designated 200.

The input of the decoder 200 is connected in signal communication with the input of the entropy decoder 210. The output of the entropy decoder is connected in signal communication with the input of the atomic decoder 220 and the input of the motion compensator 250. The output of the inverse transform module 230 providing the residue is connected in signal communication with the first non-inverting input of the combiner 270. The output of motion compensator 250 is connected in signal communication with the input of OBMC / deblocking module 260. The output of the OBMC / deblocking module 260 is connected in signal communication with the second non-inverting input of the combiner 270. The output of the synthesizer is available as an output of the decoder 200.

Unlike the MP video codec of the prior art Gabor-based MP video coding approach based on the H.263 codec, the present invention is applicable to the ITU-T H.264 / AVC coding system. Due to frame-based residual coding, OBMC is applied to the predicted picture, which is not implemented in the H.264 / AVC codec.

In one embodiment according to the present invention, the first path of the video encoding technique conforms to the H.264 standard. There is no actual coding in the first path. For example, all control data such as mode selection, predictive picture, and motion vector are stored in the buffer for the second path. The DCT transform is still applied in the first path for mode selection and motion compensation using Rate Distortion Optimization (RDO). Instead of coding the residual image using the DCT coefficients, all the remaining images are stored for the second path. In one embodiment of the present invention, it has been proposed to apply 16 × 16 limited intra-coding or H.264 standard-compliant limited intra-coding, and in particular to handle the boundary between intra-coded and inter-coded macroblocks.

In the second path, the motion vector and control data may be coded by entropy coding. The residual picture can be coded by MP. The atomic search and parameter coding may be performed, for example, in accordance with the prior art Gabor based MP video coding approach. The reproduced image is stored for the reference frame.

One of the advantages of MP video coding is that there is no blocking artifact because MP is not block-based. However, when motion prediction is performed on a block basis and is inaccurate, MP video coding still generates certain blocking artifacts at a very low bit rate. The simulation shows that the atoms appear in the moving contours, and in regions where the motion vector (MV) is not very accurate. Improved motion estimation allows atoms to better represent residuals.

To remove artifacts from motion prediction, one method involves smoothing the blurred boundary of the predicted image using an H.264-type or an improved deblocking filter. In another approach, a smoother motion model employing a superposition block (OBMC) is employed. In the prior art Gabor based MP video coding approach, a 16x16 sine window has been adapted. The NxN sine square window can be defined, for example, according to a hybrid coding technique of the prior art. A 16x16 sine window is designed for an 8x8 block, and a 16x16 block is treated as four 8x8 blocks.

However, in the H.264 standard, partitions with luma block sizes of 16 x 16, 16 x 8, 8 x 16, and 8 x 8 samples are supported. When partitions with 8x8 samples are selected, the 8x8 partition is further divided into 8x4, 4x8 or 4x4 luma samples and corresponding chroma samples. Here, four approaches for dealing with additional partition types are proposed. The first approach is to use an 8x8 sine window for a 4x4 partition. For all other partitions above 4 × 4, divide these partitions into multiple 4 × 4 partitions. The second approach is to use a 16x16 sine window for 8x8 and above partitions, but not for partitions smaller than 8x8. The third approach is to use adaptive OBMC for all partitions. All three approaches implement only OBMC and do not implement a deblocking filter, and the fourth approach is to combine OBMC with deblocking filter (s).

In addition to the redundant Garber presets of the prior art Gabor based MP video coding approach implemented for residual coding, we also suggest the use of an overcompleted base. At low bit rates, the transformed motion model does not accurately represent the natural motion of related visual characteristics, such as the moving edge. Thus, most of the residual error energy is located in these regions. Therefore, it is important to display an erroneous image using the edge detection redundant dictionary. A discrete wavelet transform (e.g., 2-D DDWT (Dual-Tree Discrete Wavelet Transform)) with low redundancy, or some other edge detection dictionary, that can be utilized for a 2-D garbage dictionary can be used . 2-D DDWT has more subbands / directions than 2-D DWT. Each subband represents one direction, which is edge-detectable. After noise shaping, the 2-D DDWT achieves a higher PSNR than the standard 2-D DWT with the same remaining coefficients. Thus, 2-D DDWT is more suitable for coding edge information. After applying OBMC to the predicted image, the erroneous image will have a smoother edge. A parametric overcomplete 2-D dictionary can be used to provide smoother edges.

Referring to FIG. 3, an exemplary method for encoding an input video sequence is generally indicated by reference numeral 300. The method 300 includes a start block 305 that sends control to a decision block 310. Decision block 310 determines whether the current frame is an I frame. If the current frame is an I frame, control is sent to a function block 355. Otherwise, control is sent to a function block 315.

The function block 355 performs H.264 standard compliant frame coding to provide an output bit stream and sends control to an end block 370.

The function block 315 performs H.264 standard compliant motion compensation and sends control to a function block 320. The function block 320 stores the motion vector (MV), the control data, and the prediction block, and sends control to decision block 325. The decision block 325 determines whether the end of the frame has been reached. Once the end of the frame has been reached, control is sent to a function block 330. Otherwise, control returns to a function block 315.

The function block 330 performs OBMC and / or deblocking filtering on the predicted image and sends control to a function block 335. [ The function block 335 obtains the residual image from the original and predicted images and sends control to a function block 340. The function block 340 codes the residual using the MP and sends control to a function block 345. The function block 345 performs entropy coding to provide an output bitstream and sends control to an end block 370.

Referring to FIG. 4, an exemplary method for decoding an input video sequence is generally indicated by reference numeral 400. The method 400 includes a start block 405 that sends control to decision block 410. The decision block 410 determines whether the current frame is an I frame. If the current frame is an I frame, control is passed to a function block 435. Otherwise, control is passed to a function block 415.

The function block 435 performs H.264 standard compliant decoding to provide the reproduced picture and sends control to an end block 470.

The function block 415 decodes motion vectors, control data, and MP atoms, and passes control to a function block 420 and a function block 425. The function block 420 reproduces the residual image using the decoded atoms and sends control to the function block 430. [ The function block 425 decodes the motion vector and other control data, and plays back the predicted picture by applying OBMC and / or deblocking filtering, and sends control to the function block 430. [ The function block 430 combines the reproduced residual image and the reproduced predicted image to provide a reproduced image and sends control to an end block 470. [

Some of the attendant advantages / features of the present invention will now be described, some of which have been described above. For example, one advantage / feature is a video encoder that encodes video signal data using a multipath video encoding technique, wherein the video encoder includes a motion estimator and a decomposition module. The motion estimator performs motion estimation on the video signal data to obtain motion residual corresponding to the video signal data in the first encoding path. The decomposition module in signal communication with the motion estimator decomposes motion residue in the subsequent encoding path.

Another advantage / feature is the video encoder as described above, wherein the multipath video coding scheme is a dual path video encoding scheme. The video encoder further includes a buffer for storing motion residues obtained in the first encoding path for subsequent use in the second encoding path, in signal communication with the motion estimator and the decomposition module. The decomposition module decomposes the motion residue using the redundant gauge dictionary set in the second encoding path.

Another advantage / feature is a video encoder using a dual path video encoding scheme as described above, wherein the motion estimator is adapted to perform the motion estimation on the first encoding path in accordance with the International Telecommunications Union, Telecommunications Division (ITU-T) H.264 standard And performs motion estimation and coding mode selection.

Another advantage / feature is a video encoder using the dual path video encoding technique as described above, wherein the video encoder further comprises a prediction module and a superposition block motion compensator. The prediction module in signal communication with the buffer forms a prediction picture corresponding to the video signal data in the first encoding path. The overlapping block motion compensator in signal communication with the buffer performs superimposed block motion compensation (OBMC) on the predictive picture using a 16x16 sine window, thereby smoothing the predictive picture in the second encoding path. The buffer stores therein the predicted picture in the first encoding path for subsequent use in the second encoding path.

Yet another advantage / feature is a video encoder using the dual path video encoding technique as described above, wherein the video encoder further comprises a prediction module and a superposition block motion compensator. The prediction module in signal communication with the buffer forms a prediction picture corresponding to the video signal data in the first encoding path. The nested block motion compensator in signal communication with the buffer performs nested block motion compensation (OBMC) only for 8 × 8 and larger partitions of the predicted picture in the second encoding path. The buffer stores therein the predicted picture in the first encoding path for subsequent use in the second encoding path.

Yet another advantage / feature is a video encoder using the dual path video encoding technique as described above, wherein the video encoder further comprises a prediction module and a superposition block motion compensator. The prediction module in signal communication with the buffer forms a prediction picture corresponding to the video signal data in the first encoding path. The nested block motion compensator in signal communication with the buffer performs the nested block motion compensation (OBMC) using an 8x8 sine window for the 4x4 partition of the predicted picture in the second encoding path. All partitions of the predicted picture are divided into 4x4 partitions when OBMC is performed in the second encoding path. The buffer stores therein the predicted picture in the first encoding path for subsequent use in the second encoding path.

Yet another advantage / feature is a video encoder using the dual path video encoding technique as described above, wherein the video encoder further comprises a prediction module and a superposition block motion compensator. The prediction module in signal communication with the buffer forms a prediction picture corresponding to the video signal data in the first encoding path. A nested block motion compensator in signal communication with the buffer performs adaptive superposition block motion compensation (OBMC) on all partitions of the predicted picture in the second encoding path. The buffer stores therein the predicted picture in the first encoding path for subsequent use in the second encoding path.

Yet another advantage / feature is a video encoder using a dual path video encoding scheme as described above, wherein the video encoder further comprises a prediction module and a deblocking filter. The prediction module in signal communication with the buffer forms a prediction picture corresponding to the video signal data in the first encoding path. A deblocking filter in signal communication with the buffer performs a deblocking operation on the predicted picture in the second encoding path. The buffer stores therein the predicted picture in the first encoding path for subsequent use in the second encoding path.

Yet another advantage / feature is a video encoder using a dual-path video encoding scheme as described above, wherein the decomposition module performs a dual-tree wavelet transform to decompose motion residuals.

Another advantage / feature is a video encoder using a dual-path video encoding technique and a dual-tree wavelet transform as described above, wherein the decomposition module selects the coefficients of the dual-tree wavelet transform using noise shaping.

Also, another advantage / feature is a video encoder using a dual path video encoding scheme as described above, wherein the decomposition module applies a parametric overcomplete 2-D dictionary to decompose motion residuals in the second encoding path.

Yet another advantage / feature is a video decoder for decoding a video bitstream, wherein the video decoder includes an entropy decoder, an atom decoder, an inverse transformer, a motion compensator, a deblocking filter, and a synthesizer. The entropy decoder decodes the video bit stream to obtain a decomposed video bit stream. An atomic decoder in signal communication with an entropy decoder decodes decomposed atoms corresponding to the decomposed bitstream to obtain decoded atoms. An inverse converter in signal communication with the atom decoder applies an inverse transform to the decoded atoms to form the reproduced residual image. The motion compensator for signal communication with the entropy decoder performs motion compensation using a motion vector corresponding to the decomposed bitstream to form a reproduced predictive image. A deblocking filter in signal communication with the motion compensator performs deblocking filtering on the reproduced predictive image to smooth the reproduced predictive image. The synthesizer that is in signal communication with the inverse transformer and the superposed block motion compensator synthesizes the reproduced predicted image and the residual image to obtain the reproduced image.

These and other features and advantages of the present invention will be readily ascertainable by those skilled in the art based on the teachings herein. It will be appreciated that the teachings of the present invention may be implemented in various forms of hardware, software, firmware, special purpose processors, or combinations thereof.

Most preferably, the teachings of the present invention are implemented as a combination of hardware and software. Further, the software can be implemented as an application program that is actually implemented in the program storage unit. The application program may be uploaded to and executed by a machine having any suitable structure. Preferably, the machine is implemented in a computer platform having hardware such as one or more central processing unit (CPU), RAM, and input / output (I / O) The computer platform may also include an operating system and microinstruction code. The various processes and functions described herein may be part of the micro-instruction code or part of the application program, or any combination thereof, that may be executed by the CPU. In addition, various other peripherals such as additional data storage and printing can be connected to the computer platform.

In addition, since some of the constituent system elements and methods shown in the accompanying drawings are preferably implemented in software, the actual connection between system components or process functional blocks may vary depending on the manner in which the present invention is programmed. Throughout the teachings of this specification, those skilled in the art will be able to devise the same and similar implementations or configurations of the present invention.

Although illustrative embodiments have been described herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to these precise embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention . All such changes and modifications are intended to be included within the scope of the present invention as defined in the appended claims.

Claims (24)

1. A video encoder for encoding video signal data using a multipath video encoding technique,
A motion estimator (116) for performing motion estimation on the video signal data to obtain a motion residual corresponding to the video signal data in a first encoding path,
A decomposition module 174 in signal communication with the motion estimator and decomposing the motion residue in a subsequent encoding path,
/ RTI > The method according to claim 1,
The multi-path video coding scheme is a two-path video coding scheme,
Wherein the video encoder further comprises a buffer (118) in signal communication with the motion estimator and the decomposition module and storing the motion residue obtained in the first encoding path for subsequent use in a second encoding path,
The decomposition module (174) decomposes the motion residue using a redundant Gabor dictionary set in the second encoding path. 3. The method of claim 2,
The motion estimator 116 performs the motion estimation and coding mode selection in accordance with the H.264 standard of the International Telecommunication Union (ITU-T) in the first encoding path Video encoder. 3. The method of claim 2,
A prediction module (124, 126) in signal communication with the buffer and forming a predictive picture corresponding to the video signal data in the first encoding path,
Communicating with the buffer and performing overlapping block motion compensation (OBMC) on the predicted picture using a 16x16 sine-square window to estimate the prediction in the second encoding path The superimposed block motion compensator 170, which smooths the image,
Further comprising:
Wherein the buffer stores therein the predictive picture in the first encoding path for subsequent use in the second encoding path. 3. The method of claim 2,
A prediction module (124, 126) in signal communication with the buffer and forming a predictive picture corresponding to the video signal data in the first encoding path,
A superposed block motion compensator (170) in signal communication with the buffer and performing superposed block motion compensation (OBMC) only on 8x8 and larger partitions of the predicted picture in the second encoding path,
Further comprising:
Wherein the buffer stores therein the predictive picture in the first encoding path for subsequent use in the second encoding path. 3. The method of claim 2,
A prediction module (124, 126) in signal communication with the buffer and forming a predictive picture corresponding to the video signal data in the first encoding path,
A superposed block motion compensator (170) in signal communication with the buffer and performing a superposition block motion compensation (OBMC) using an 8x8 sine window for 4x4 partitions of the predicted picture in the second encoding path,
Further comprising:
All partitions of the predictive picture are partitioned into 4x4 partitions when OBMC is performed in the second encoding path,
Wherein the buffer stores therein the predictive picture in the first encoding path for subsequent use in the second encoding path. 3. The method of claim 2,
A prediction module (124, 126) in signal communication with the buffer and forming a predictive picture corresponding to the video signal data in the first encoding path,
A superposed block motion compensator (170) in signal communication with the buffer and performing adaptive superposition block motion compensation (OBMC) on all partitions of the predictive picture in the second encoding path,
Further comprising:
Wherein the buffer stores therein the predictive picture in the first encoding path for subsequent use in the second encoding path. 3. The method of claim 2,
A prediction module (124, 126) in signal communication with the buffer and forming a predictive picture corresponding to the video signal data in the first encoding path,
A deblocking filter (170) in signal communication with the buffer and performing a deblocking operation on the predicted picture in the second encoding path,
Further comprising:
Wherein the buffer stores therein the predictive picture in the first encoding path for subsequent use in the second encoding path. 3. The method of claim 2,
The decomposition module 174 performs a dual-tree wavelet transform to decompose the motion residue. 10. The method of claim 9,
The decomposition module 174 selects the coefficients of the dual-tree wavelet transform using noise shaping. 3. The method of claim 2,
The decomposition module 174 applies parametric over-complete 2-D dictionaries to decompose the motion residue in the second encoding path. CLAIMS 1. A method for encoding video signal data using a multipath video encoding technique,
Performing motion estimation on the video signal data to obtain a motion residual corresponding to the video signal data in a first encoding path (315)
Decomposing the motion residue in a subsequent encoding path (340)
/ RTI > 13. The method of claim 12,
The multi-path video coding scheme is a two-path video coding scheme,
The method further includes storing (320) the motion residue obtained in the first encoding path for subsequent use in a second encoding path,
The decomposition step (340) decomposes the motion residue using a redundant gauge dictionary set in the second encoding path. 14. The method of claim 13,
Wherein the motion estimation and coding mode selection is performed in accordance with the International Telecommunication Union Telecommunication Sector (ITU-T) H.264 standard in the first encoding path. 14. The method of claim 13,
Forming (315) a predictive image corresponding to the video signal data in the first encoding path,
Storing (320) the predictive image in the first encoding path,
(330) performing a superimposed block motion compensation (OBMC) on the predictive image using a 16x16 sine window and smoothing the predictive image in the second encoded path,
≪ / RTI > 14. The method of claim 13,
Forming (315) a predictive image corresponding to the video signal data in the first encoding path,
Storing (320) the predictive image in the first encoding path,
Performing (330) overlap block motion compensation (OBMC) on only 8x8 and larger partitions of the predicted picture in the second encoding path,
≪ / RTI > 14. The method of claim 13,
Forming (315) a predictive image corresponding to the video signal data in the first encoding path,
Storing (320) the predictive image in the first encoding path,
Performing (330) overlap block motion compensation (OBMC) using an 8x8 sine window for 4x4 partitions of the predicted picture in the second encoding path,
Further comprising:
Wherein all partitions of the predictive image are partitioned into 4x4 partitions when OBMC is performed in the second encoding path. 14. The method of claim 13,
Forming (315) a predictive image corresponding to the video signal data in the first encoding path,
Storing (320) the predictive image in the first encoding path,
Performing (330) adaptive superposition block motion compensation (OBMC) on all partitions of the predictive picture in the second encoding path,
≪ / RTI > 14. The method of claim 13,
Forming (315) a predictive image corresponding to the video signal data in the first encoding path,
Storing (320) the predictive image in the first encoding path,
Performing (330) a deblocking operation on the predictive picture in the second encoding path,
≪ / RTI > 14. The method of claim 13,
The decomposition step (340) performs a dual-tree wavelet transform to decompose the motion residue. 21. The method of claim 20,
The decomposition step (340) selects the coefficients of the dual tree wavelet transform using noise shaping. 14. The method of claim 13,
The decomposition step (340) applies parametric overcomplete 2-D dictionaries to decompose the motion residue in the second encoding path. A video decoder for decoding a video bitstream,
An entropy decoder 210 for decoding the video bitstream to obtain a decomposed video bitstream,
An atom decoder 220 in signal communication with the entropy decoder and decoding the decomposed atoms corresponding to the decomposed bit stream to obtain decoded atoms;
An inverse transformer (230) in signal communication with the atomic decoder, applying an inverse transformation to the decoded atoms to form a reconstructed residual image,
A motion compensator (250) for signal communication with the entropy decoder, performing motion compensation using motion vectors corresponding to the decomposed bitstream to form a reconstructed predictive image,
A deblocking filter (260) for signal communication with the motion compensator and performing de-blocking filtering on the reconstructed predictive picture to smooth the reconstructed predictive picture;
A synthesizer 270 for signal communication with the inverse transformer and the deblocking filter 260 to combine the reconstructed predictive image and the residual image to obtain a reconstructed image,
/ RTI > A method for decoding a video bitstream,
(405) decoding the video bitstream to obtain a decomposed video bitstream,
Decoding (415) decoding the decomposed atoms corresponding to the decomposed bitstream to obtain decoded atoms,
Applying an inverse transformation to the decoded atoms to form a reconstructed residual image 420,
A step 425 of performing motion compensation using motion vectors corresponding to the decomposed bitstream to form a reconstructed predictive image,
(425) performing deblocking filtering on the reconstructed predictive picture to smooth the reconstructed predictive picture;
Combining the reconstructed predictive image and the residual image to obtain a reconstructed image (430)
/ RTI >

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