Patent application number | Description | Published |
20120106624 | Method and Apparatus of Slice Boundary Filtering for High Efficiency Video Coding - An apparatus and method for video coding having intra-slice deblocking, intra-slice adaptive loop filter, and intra-slice adaptive offset are disclosed. In a video coding system, a picture is often divided into slices and each slice is independently processed so that errors or missing data from one slice cannot propagate to any other slice within the picture. In the recent high efficiency video coding (HEVC) development, deblock filtering (DF), adaptive loop filter (ALF) and adaptive offset (AO) may be applied to reconstructed slices. When the processing is applied across slice boundaries, it may rely on pixels outside the current slice and cause dependency of the current slice on other slice(s). Consequently, the DF/ALF/AO processing on a reconstructed slice may have to wait until the reconstructed slices that it is dependent from complete the DF/ALF/AO processing. To overcome the slice boundary issue, intra-slice DF/ALF/AO is developed that does not rely on any pixel outside the currently slice. An optional slice boundary filter may be applied to slice boundaries after all slices are processed by the intra-slice DF/ALF/AO. | 05-03-2012 |
20120128067 | Apparatus and Method of Constrained Partition Size for High Efficiency Video Coding - An apparatus and method for video coding and decoding with constrained PU partition are disclosed. In the High Efficient Video Coding (HEVC) system, rate-distortion function or other performance criterion usually is evaluated for various CU partition and PU partition during the encoding process in order to select a configuration with best possible performance. The PU design in the current HEVC development results in some redundancy that causes rate-distortion function or other performance criterion repeatedly evaluated for same PU configuration. Accordingly, constrained PU partition is developed to eliminate or reduce the redundancy in processing. Furthermore, necessary syntax to convey the information related to constrained PU partition between an encoder and a decoder is developed. Systems embodying the present invention has been shown to result in sizeable reduction in encoding and decoding time while the performance in terms of RD-rate remains approximately the same or slightly higher than a conventional HEVC system. | 05-24-2012 |
20120195366 | Method and Apparatus of Adaptive Inter Mode Coding Using Variable Length Codes - A method and apparatus for adaptive inter prediction mode coding are disclosed. In the current HEVC, a fixed set of variable length codes is used for the underlying video data, which may not optimally match the statistics of underlying video data. Consequently, the compression efficiency associated with the fixed set of variable length codes will be compromised. Accordingly, an adaptive coding scheme for inter prediction modes is disclosed. The variable length codes used for each inter prediction mode in each coding unit depth is adaptively determined by its respective statistics. The statistics can be measured as the frequency of occurrence of each mode. In one embodiment according to the present invention, counters are used to collect the statistics. According to one embodiment of the present invention, the statistics of inter prediction modes are collected from the previous slice and the set of variable length codes is determined for the subsequent slice (immediately following the previous slice) accordingly. According to another embodiment of the present invention, the statistics of inter prediction modes are updated for each coding unit and the variable length code for each mode is adjusted according to the statistics change during the coding process. According to another embodiment of the present invention, the variable length code for each mode is reset in the beginning of each slice. The reset code word table is either a predefined code word table for whole sequence or a code word table determined by the previous slice. | 08-02-2012 |
20120230411 | Method and Apparatus of Transform Unit Partition with Reduced Complexity - Three block concepts are introduced in HEVC: coding unit (CU), prediction unit (PU), and transform unit (TU). The overall coding structure is characterized by the various sizes of CU, PU and TU in a recursive fashion. For transform processing in current HEVC, a hierarchy RQT (Residual Quad Tree) is used and the TU size is related to the CU size, but independent of the PU size. This results in high encoding complexity and also causes increased processing time to process the syntax of residual quad tree. Accordingly a modified transform unit partition with reduced complexity is disclosed. According to an embodiment, the TU size may be restricted to the minimum of PU width and height, except for a 2N×2N coding unit with the 2N×2N partition type. In another embodiment, the maximum TU size equals to maximum of PU width and height, and the minimum TU size equals to minimum of the PU width and height, except for a 2N×2N coding unit with the 2N×2N partition type. In yet another embodiment, the TU size is selected between 2N×2N and N×N for the 2N×2N, 2N×N, N×2N and N×N partition types. The syntax element, split_transform_flag, is used to indicate the selection of 2N×2N or N×N TU size when needed. Furthermore, a method with reduced complexity of selecting the best merge candidate for the 2N×2N CU merge mode is disclosed. The method relies on R-D cost associated with the motion vector of merge candidate to reduce required computation. | 09-13-2012 |
20130022129 | Method and Apparatus for Compressing Coding Unit in High Efficiency Video Coding - In HEVC (High Efficiency Video Coding), a 2N×2N coding unit can be partitioned into various partition types hierarchically. The coding system uses a criterion to determine the best partition, where RD-rate is often used as the criterion. N×N partition at level k becomes redundant if 2N×2N at level k+1 will be evaluated. In order to eliminate the above redundancy, the allowable partition sizes are constrained according to a method previously disclosed. In the current invention, the complexity is further reduced. According to one embodiment, N×N partition is not allowed for any INTER mode regardless of the coding unit size. Furthermore, flexibility is provided so that either the method and apparatus with further complexity reduction can be selected or an alternative method and apparatus can be selected. Syntaxes to support embodiments according to the present invention are also disclosed. | 01-24-2013 |
20130266064 | Method and Apparatus for Intra Mode Coding in HEVC - A method and apparatus for Intra prediction mode encoding or decoding based on multi-level most probable modes (MPMs) are disclosed. In one embodiment according to the present invention, the method and apparatus for encoding or decoding Intra prediction mode for 4×4 prediction unit (PU) use 19 Intra mode candidates to have full directional coverage or 35 Intra mode candidates as used by 8×8, 16×16 and 32×32 PUs. In another embodiment of the present invention, three MPMs are used to code the Intra modes. Various methods to derive the three MPMs based on the Intra modes of neighboring blocks are disclosed. In yet another embodiment of the present invention, the coding method for the remaining modes comprises fixed length coding. In addition, variable length coding for the remaining modes are also disclosed. | 10-10-2013 |
20130266207 | METHOD FOR IDENTIFYING VIEW ORDER OF IMAGE FRAMES OF STEREO IMAGE PAIR ACCORDING TO IMAGE CHARACTERISTICS AND RELATED MACHINE READABLE MEDIUM THEREOF - A method for identifying an actual view order of image frames of a stereo image pair includes at least the following steps: receiving the image frames; obtaining image characteristics by analyzing the image frames according to an assumed view order; and identifying the actual view order by checking the image characteristics. In addition, a machine readable medium storing a program code is provided. The program causes a processor to perform at least the following steps for identifying an actual view order of image frames of a stereo image pair when executed by the processor: receiving the image frames; obtaining image characteristics by analyzing the image frames according to an assumed view order; and identifying the actual view order by checking the image characteristics. | 10-10-2013 |
20140086323 | METHOD AND APPARATUS FOR CODING OF INTRA PREDICTION MODE - Embodiments according to the present invention configure the intra prediction mode candidates into multi-level MPM sets, which comprise at least a first-level MPM set and a second-level MPM set. Encoding or decoding a current intra prediction mode is based on the multi-level MPM sets, where one syntax element of the syntax information to be generated or decoded respectively is associated with evaluating the current intra prediction mode using the first-level MPM set. A method and apparatus for spectively is associated with evaluating the current intra prediction mode using the first-level MPM set. A method and apparatus for chroma intra prediction mode encoding and decoding are also disclosed. The chroma intra prediction mode set includes a Luma-based chroma prediction Mode (LM), a Direct Mode (DM) and four other modes. The codeword set comprises variable-length codewords and fixed-length codewords, and the fixed-length codewords are longer than the variable-length codewords. The variable-length codewords are used for the DM and LM, and the fixed-length codewords are used for the four other modes. | 03-27-2014 |
20140140404 | METHOD AND APPARATUS FOR INTRA PREDICTION USING NON-SQUARE BLOCKS - A method and apparatus for Intra prediction of a block based on neighboring pixels around the block are disclosed. Embodiments according to the present invention use square blocks as well as non-square blocks for Intra prediction. For a 2N×2N Luma CU (coding unit), the CU can be partitioned into 2N×N, N×2N, 2N×2N or N×N PUs. The 2N×N and N×2N PUs can be further processed by either square transforms only or both non-square and square transforms. In one embodiment, the 2N×N PU or the N×2N PU is processed as two N×N TUs (transform units) and each of the N×N TU is further split into smaller N×N TUs based on quad-tree split. In another embodiment, the 2N×N and N×2N PUs are processed as two 2N×0.5N and 0.5N×2N TUs respectively. | 05-22-2014 |
20140177728 | METHOD AND SYSTEM OF TRANSFORM BLOCK PROCESSING ACCORDING TO QUANTIZATION MATRIX IN VIDEO CODING - A method and system for processing transform blocks according to quantization matrices in a video coding system are disclosed. Embodiments of the present invention derive one or more derived quantization matrices from one or more initial quantization matrices or from one previously derived quantization matrix. In one embodiment, the initial quantization matrices include a 4×4 and 8×8 quantization matrices, which can be either default or user-defined. All quantization matrices larger than 8×8 can be derived from the 4×4 and 8×8 initial quantization matrices. Non-square quantization matrices can be derived from at least one initial square quantization matrix or at least one derived square quantization matrix. Individual initial quantization matrices may be used to derive respective larger quantization matrices. Furthermore, the individual initial quantization matrices may be derived from larger quantization matrices designed for corresponding transform sizes. Syntax design to enable the quantization matrix representation is also disclosed. | 06-26-2014 |
20140211850 | METHOD AND APPARATUS FOR PREDICTION MODE AND PARTITION MODE SYNTAX CODIND FOR CODING UNITS IN HEVC - A method and apparatus for coding of syntax elements are disclosed to allow prediction units in P and B slices to share the same syntax coding table. In one embodiment according to the present invention, the method and apparatus coding of syntax elements selectively apply a syntax coding table to encode or decode the syntax element associated with the partition mode of a coding unit of a picture region according to the slice type of the picture region. A first syntax coding table is used to process the syntax element if the slice type is an I mode and a second syntax coding table is used to process the syntax element if the slice type is not an I mode. | 07-31-2014 |
20140328396 | METHOD AND APPARATUS FOR CONTEXT ADAPTIVE BINARY ARITHMETIC CODING OF SYNTAX ELEMENTS - A method and apparatus for context-adaptive Start arithmetic coding (CABAC) of a syntax element are disclosed. The bin string corresponding to a syntax element is processed by context-adaptive arithmetic coding with a reduced number of contexts using the bin-level bypass mode, bin-level context sharing, or both. The syntax element belongs to a group comprising merge_idx, ref_idx_lc/ref_idx_10/ref_idx_11, pred_type, and cu_qp_delta. In one embodiment, the syntax element corresponds to merge_idx and three bins of the bin string with bin indices corresponding to 1, 2 and 3 are coded in the bin by-pass mode. In another embodiment, the syntax element corresponds to ref_idx_lc/ref_idx_10/ref_idx_11 and one or more bins of the bin string with bin indices larger than 1 for larger than 2 are coded in the bin bypass mode. | 11-06-2014 |
20150049817 | Method and Apparatus for Compressing Coding Unit in High Efficiency Video Coding - In HEVC (High Efficiency Video Coding), a 2N×2N coding unit can be partitioned into various partition types hierarchically. The coding system uses a criterion to determine the best partition, where RD-rate is often used as the criterion. N×N partition at level k becomes redundant if 2N×2N at level k+1 will be evaluated. In order to eliminate the above redundancy, the allowable partition sizes are constrained according to a method previously disclosed. In the current invention, the complexity is further reduced. According to one embodiment, N×N partition is not allowed for any INTER mode regardless of the coding unit size. Furthermore, flexibility is provided so that either the method and apparatus with further complexity reduction can be selected or an alternative method and apparatus can be selected. Syntaxes to support embodiments according to the present invention are also disclosed. | 02-19-2015 |