Patent application number | Description | Published |
20110274158 | Method and Apparatus of Adaptive Loop Filtering - In a block-based motion compensated system, coding noises may arise due to lossy operations such as quantization. Deblocking is often used to alleviate visibility of coding artifacts by applying filtering across block boundaries adaptively. In the recent HEVC development, adaptive loop filtering (ALF) is being adopted to process deblocked reconstruction frames. Adaptive loop filtering is applied to reconstructed video data across multiple frames to reduce visibility of coding artifacts in the temporal domain. In a HEVC system, conventional ALF can be selectively turned ON or OFF for each block in a frame or a slice. The advanced ALF disclosed here allows a choice of multiple filter sets that can be applied to the reconstructed video data adaptively. Furthermore, the advanced ALF adopts a new unit for the filtering process to apply so that more flexible and/or localized processing can be provided. Furthermore, the advanced ALF allows a decoder to derive respective information for applying the filtering process without side information. | 11-10-2011 |
20110305274 | APPARATUS AND METHOD OF ADAPTIVE OFFSET FOR VIDEO CODING - An apparatus and method for content adaptive offset restoration are described. In video processing system, due to various mathematic operations applied to the data, the mean intensity of the processed video data may be shifted from mean intensity of original data. The intensity offset will result in noticeable artifacts. Accordingly adaptive offset restoration is disclosed which derives intensity offset for a region of a picture based on the dynamic characteristics of underlying pixels. According to the characteristics measurement of underlying pixels, the pixels in each region are classified into classes and an intensity offset is determined for each class. The characteristics measurement may be based on pixel patterns at an underlying pixel and the characteristics may be related to edge, peak and valley at the underlying pixel. Alternatively, the characteristics measurement may be based on pixel intensity of an underlying pixel and the pixel intensity is partitioned into multiple bands for classification. | 12-15-2011 |
20110305277 | SYSTEM AND METHOD FOR CONTENT ADAPTIVE CLIPPING - A system and method of content adaptive pixel intensity processing are described. In video processing system, due to various mathematic operations applied to the data, the processed video data may be become exceeding a range of original data and result in artifacts. Content adaptive clipping method is disclosed which takes into account the dynamic characteristics of the video data. Accordingly the method configures the video data into a predefined set which can be a partial picture, a frame or a group of frames. The data range of the original associated with the predefined set is determined The processed video data is clipped according to the range computed for the predefined set. | 12-15-2011 |
20120008688 | Method and Apparatus of Temporal Motion Vector Prediction - An apparatus and method for motion vector prediction for a current block in a picture are disclosed. In video coding systems, the spatial and temporal redundancy is exploited using spatial and temporal prediction to reduce the information to be transmitted. Motion Vector Prediction (MVP) has been used to further conserve the bitrate associated with motion vector. In conventional temporal MVP, the predictor is often based on a single candidate such as the co-located motion vector in the previous frame/picture. If the co-located motion vector in the previous frame/picture does not exist, the predictor for the current block is not available. A technique for improved MVP is disclosed where the MVP utilized multiple candidates based on co-located motion vectors from future and/or past reference pictures. The candidates are arranged according to priority order to provide better availability of MVP and also to provide more accurate prediction. Furthermore, the MVP technique disclosed can be operated in a closed-loop fashion so that no additional side information or minimum additional side information is required. | 01-12-2012 |
20120039383 | CODING UNIT SYNCHRONOUS ADAPTIVE LOOP FILTER FLAGS - An apparatus and method for coding unit-synchronous adaptive loop filtering (ALF) for an image area that is partitioned into a plurality of coding units are disclosed. In a conventional approach, the slice-level bitstream cannot be generated until all coding units in a slice are processed since the ALF filter coefficients are determined based on reconstructed pixels and original pixels of a slice. According to one embodiment, the method processes the coding units in the image area one after the other to generate a CU-level bitstream. The method also reconstructs the coding units to from reconstructed coding units which are subject to adaptive loop filtering. Upon the availability of reconstructed coding units for the image area, the method derives filter coefficients for the ALF filter based on the reconstructed pixels and original pixels in the image area. The designed ALF filter is then tested for each coding unit to determine whether the ALF filter should be applied to the coding unit and the decision is indicated by an ALF flag. After all ALF flags are determined, an image area header is created by incorporating the filter coefficients and ALF flags in the header. The header and the CU-level data previously created are combined into an image area level bitstream. An apparatus to perform the steps recited in the method is also disclosed. | 02-16-2012 |
20120082241 | Method and Apparatus of Adaptive Loop Filtering - A method and apparatus for processing in-loop reconstructed video using an in-loop filter is disclosed. In the recent HEVC development, adaptive loop filtering (ALF) is being adopted to process in-loop reconstruction video data, where ALF can be selectively turned ON or OFF for each block in a frame or a slice. An advanced ALF is disclosed later that allows a choice of multiple filter sets that can be applied to the reconstructed video data adaptively. In the present disclosure, pixels of the in-loop reconstructed video data are divided into a plurality of to-be-filtered regions, and an in-loop filter from a filter set is determined for each to-be-filtered region based on a rate-distortion optimization procedure. According to one embodiment of the present invention, computation of cost function associated with the rate-distortion optimization procedure is related to correlation values associated with original video data and the in-loop reconstructed video data. Furthermore, the correlation values can be shared by the multiple candidate filters during the rate-distortion optimization procedure for said each to-be-filtered region. In another embodiment, the correlation values can be shared by multiple candidate to-be-filtered regions of an area of the in-loop reconstructed video data during the rate-distortion optimization procedure for the area of the in-loop reconstructed video data. | 04-05-2012 |
20120082244 | Method and Apparatus of Region-Based Adaptive Loop Filtering - In a block-based motion compensated system, coding noises may arise due to lossy operations. Adaptive loop filter (ALF) is a technique used to improve the quality. A pixel adaptive (PA) ALF method was developed that uses the Sum-modified Laplacian Measure (SLM) to classify pixels and applies a respective ALF filter to each pixel according to the SLM. While the PA ALF achieves better performance over a conventional single filter (SF) based ALF, the PA ALF causes higher complexity and consumes more power due to the high complexity and per-pixel filter switching. Accordingly region based ALF scheme is disclosed which allows adaptive filter selection on a region by region basis and does not require per-pixel filter switching. In one embodiment according to the present invention, a picture is divided into M×N regions. The region based ALF also allows region merging for the M×N regions to improve performance. In another aspect of the present invention, the optimal ALF design also takes into consideration of the system complexity by using rate-distortion-complexity optimization (RDCO). The RDCO technique is also applied to sample adaptive offset (SAO) design. | 04-05-2012 |
20120106622 | Method and Apparatus of Slice Grouping for High Efficiency Video Coding - In the H.264/AVC standard, one of the new characteristics is the possibility of dividing an image in regions called slice groups. The use of slice groups provides various possible advantages such as prioritized transmission, error resilient transmission, and etc. The slice groups can be formed by flexible macroblock ordering (FMO), where each picture can be divided into slice groups in different scan patterns of the macroblocks. In the high efficiency video coding (HEVC) under development, a more flexible block structure, called coding unit (CU), is used as the unit to process video data. The picture is first divided into largest CUs (LCUs) and each LCU is adaptively split into smaller CUs using a quadtree until leaf CUs are reached. In the current HEVC development, there is neither slice nor slice group structure being considered. The LCU size used for HEVC is 16 times as large as the macroblock size used in the H.264/AVC standard. Therefore, it is very desirable to develop slice and slice group structure suited for HEVC to offer various benefits of error resilience, parallel processing, reduced line (row) buffer requirement, and etc. Accordingly, slice group types including raster scan type, vertical stripe type, regions of interest type and full flexibility type are developed for HEVC. Furthermore, various syntax elements are incorporated in the sequence header or the picture header to convey information associated with the slice group structure. | 05-03-2012 |
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 |
20120106652 | Apparatus and Method for High Efficiency Video Coding Using Flexible Slice Structure - An apparatus and method for video coding based on flexible slice structure are disclosed. In the recent high efficiency video coding (HEVC) development, the slice may contain multiple LCUs instead of macroblocks. The LCU size being considered is 64×64 pixels which is much larger than the macroblock size of 16×16 pixels. Compared with the macroblock aligned slice for H.264, the LCU-aligned slice for HEVC does not provide enough granularities for dividing video frames. Consequently, a flexible slice structure is developed where slice partition is based on smaller coding units. In the flexible slice structure, the first LCU and the last LCU of the slice are allowed to be a fractional LCU, which is derived from a whole LCU using quadtree partition. Syntax elements are also developed to enable conveyance of flexible slice structure between an encoder and a decoder efficiently. | 05-03-2012 |
20120114034 | Method and Apparatus of Delta Quantization Parameter Processing for High Efficiency Video Coding - In the current high efficiency video coding development, each LCU has its own quantization parameter (QP) and the difference between a current QP and a reference QP is transmitted instead of the QP value itself. Since the LCU is much larger than the macroblock of AVC/H.264, using one delta QP per LCU may cause rate control unable to adapt to the bitrate quickly enough. Consequently there is a need to adopt delta QP in units smaller than LCU to provide more granular rate control. Furthermore, it is desirable to develop a system that is capable of facilitating more flexible delta QP. Accordingly, adaptive quantization parameter processing is disclosed where a QP minimum CU size for incorporating or deriving a delta QP is indicated selectively in the slice level or in the sequence/picture level. In one variation, the delta QP is incorporated or derived only if nonzero quantized transform coefficients exist in a leaf CU that is larger than the QP minimum CU size. In another variation, quantization parameter information is only incorporated or derived when a leaf CU has any nonzero quantized transform coefficient. In yet another variation, a flag is used to indicate whether one delta QP per LCU is transmitted if the LCU has any nonzero quantized transform coefficient or one delta QP per leaf CU is transmitted if the leaf CU has any nonzero quantized transform coefficient. | 05-10-2012 |
20120128060 | Method and Apparatus of Spatial Motion Vector Prediction - An apparatus and method for deriving a motion vector predictor or a motion vector predictor candidate or a motion vector or a motion vector candidate for a current block are disclosed. In video coding systems, the spatial and temporal redundancy is exploited using spatial and temporal prediction to reduce the information to be transmitted or stored. Motion Vector Prediction (MVP) has been used to further conserve the bitrate associated with motion vector coding. The MVP technique being developed for the current HEVC only considers the motion vector having the same reference list and the same reference picture index as the current block to be an available spatial motion vector predictor candidate. It is desirable to develop a MVP scheme that can improve the availability of the motion vector predictor candidate based on motion vectors from the spatially neighboring block. Accordingly, an apparatus and method for determining a motion vector predictor or motion vector predictor candidate or motion vector or motion vector candidate for a current block based on motion vectors associated with reference pictures in list | 05-24-2012 |
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 |
20120134415 | Method and Apparatus of Extended Motion Vector Predictor - A method and apparatus for determining a motion vector predictor (MVP) or a MVP candidate based on a MVP set are disclosed. In video coding systems, the spatial and temporal redundancy is exploited using spatial and temporal prediction to reduce the video data to be transmitted or stored. Motion vector prediction has been used to further conserve the bitrate associated with motion vector coding. Motion vector prediction technique being developed for the current high efficiency video coding (HEVC) only uses a MVP candidate set including spatial MVP candidates and a temporal candidate corresponding to the co-located block. In the current disclosure, the spatial and temporal motion vector predictor set is extended to include at least one spatially neighboring block associated with list 0 reference pictures and list 1 reference pictures, and co-located block and its neighboring block associated with list 0 reference pictures and list 1 reference pictures. | 05-31-2012 |
20120134416 | Method and Apparatus for Derivation of MV/MVP Candidate for Inter/Skip/Merge Modes - A method and apparatus for deriving a temporal motion vector predictor (MVP) are disclosed. The MVP is derived for a current block of a current picture in Inter, or Merge, or Skip mode based on co-located reference blocks of a co-located block. The co-located reference blocks comprise an above-left reference block of the bottom-right neighboring block of the co-located block. The reference motion vectors associated with the co-located reference blocks are received and used to derive the temporal MVP. Various configurations of co-located reference blocks can be used to practice the present invention. If the MVP cannot be found based on the above-left reference block, search for the MVP can be continued based on other co-located reference blocks. When an MVP is found, the MVP is checked against the previously found MVP. If the MVP is the same as the previously found MVP, the search for MVP continues. | 05-31-2012 |
20120140825 | Method and Apparatus of Video Coding Using Picture Structure with Low-Delay Hierarchical B Group - A method and apparatus for encoding a video sequence comprising a plurality of pictures are disclosed. In video coding systems, the temporal redundancy is exploited using motion compensated prediction. The video sequence is often organized into multiple GOP (group of pictures) where different types of GOP may be used. In conventional coding systems, IPPP and IBBP GOP structure is often used. In H.264/AVC and the emerging High Efficiency Video Coding (HEVC), hierarchical GOP structure, including hierarchical P GOP structure and hierarchical B GOP structure, has been introduced to allow temporal scalability. Furthermore, low-delay IBBB GOP structure has been also introduced, for low-delay application. In the present invention, a low-delay hierarchical B GOP structure is disclosed. The new structure uses low-delay B-pictures only so as to minimize the processing delay while the hierarchical structure provides the temporal scalability. The low-delay hierarchical B GOP structure has been shown to result in substantial improvement in coding efficiency | 06-07-2012 |
20120177103 | APPARATUS AND METHOD OF EFFICIENT SAMPLE ADAPTIVE OFFSET - For sample adaptive offset, classification may be used to classify the pixels into multiple categories and pixels in each category are offset compensated using an offset value for the category. The classification may be based on values of the current pixel and its neighboring pixels before SAO compensation. Therefore, the SAO compensated pixel cannot be written back to the current pixel location until the category for all pixels are determined. An embodiment of the present invention stores the relation between the current pixel and said one or more neighboring pixels so that the SAO compensated current pixel can replace the current pixel without buffering the to-be-processed pixels for classification. The SAO process may be performed on a region by region basis to adapt to the local characteristics of the picture. Rate-distortion optimization (RDO) is often used to guide the mode decision, such as region splitting/region merging decision. Computations associated with the RDO process usually are very computational intensive. Accordingly, distortion reduction estimation is developed which can substantially reduce the required computation associated with RDO. | 07-12-2012 |
20120177107 | Apparatus and Method of Sample Adaptive Offset for Video Coding - An apparatus and method for sample adaptive offset to restore intensity shift of processed video data are described. In a video coding system, the video data are subject to various processing such as prediction, transformation, quantization, deblocking, and adaptive loop filtering. Along the processing path in the video coding system, certain characteristics of the processed video data may be altered from the original video data due to the operations applied to video data. For example, the mean value of the processed video may be shifted. Therefore, the pixel intensity shift has to be carefully compensated or restored to alleviate the artifacts. Accordingly a sample adaptive offset scheme is disclosed that can take into consideration of the dynamic characteristics within a frame using a region partition scheme. Furthermore, the sample adaptive offset scheme also supports multiple SAO types that can be tailored to the characteristics of processed video data and achieve better quality. | 07-12-2012 |
20120207227 | Method and Apparatus for Slice Common Information Sharing - A method and apparatus for sharing information in a video coding system are disclosed. Embodiments according to the present invention use an information sharing flag to determine whether to share in-loop filter information in the picture level. The information sharing flag may be incorporated in the sequence level, the picture level or the slice level to indicate whether information sharing is enabled. Multiple information sharing flags may also be used to adaptively control information sharing. Furthermore, method and apparatus of using multiple Adaptation Parameter Sets (APSs) for information sharing of in-loop filters are disclosed. APS identifiers of in-loop filters may be incorporated in the slice header to allow each of the in-loop filters select respective filter information from the multiple APSs. A flag is incorporated in SPS to indicate whether multiple APS or single APS is used. Various exemplary syntax designs are disclosed to illustrate information sharing. | 08-16-2012 |
20120236941 | Method and Apparatus for Derivation of Spatial Motion Vector Candidate and Motion Vector Prediction Candidate - An apparatus and method for deriving a motion vector predictor are disclosed. In video coding systems, the spatial and temporal redundancy is exploited using spatial and temporal prediction to reduce the information to be transmitted or stored. Motion vector prediction has been used to further conserve the bitrate associated with motion vector coding. In a conventional coding system, a motion vector predictor (MVP) is selected from the spatial MVPs and temporal MVP. The spatial MVP according to a conventional approach is based on motion vectors (MVs) of neighboring blocking pointing to a target reference picture in a given reference list. Embodiments according to the present invention perform the MVP search among an extended search set including MVs pointing to other reference pictures in the given reference list or the other reference list and MVs pointing to the target reference picture in the given reference list or the other reference list. Other aspects of the present invention address the search order of the search set and configuration of neighboring blocks. | 09-20-2012 |
20120236942 | Method and Apparatus for Deriving Temporal Motion Vector Prediction - A method and apparatus for deriving a temporal motion vector predictor (MVP) are disclosed. The MVP is derived for a current block of a current picture in Inter, or Merge, or Skip mode based on co-located reference blocks of a co-located block and a flag is used to indicate the co-located picture. More than one co-located reference blocks can be used to derive the temporal MVP and the co-located reference blocks can be selected from the co-located block as well as neighboring blocks of the co-located block. A search set comprises search motion vectors associated with the co-located reference block(s) is formed. The search motion vector (MV) corresponding to the co-located reference block in the same reference list is searched before the search MV in a different reference list. Various schemes to accommodate implicit method of deriving co-located picture are also disclosed. | 09-20-2012 |
20120294353 | Apparatus and Method of Sample Adaptive Offset for Luma and Chroma Components - A method and apparatus for processing reconstructed video using in-loop filter in a video coding system are disclosed. The method uses chroma in-loop filter indication to indicate whether chroma components are processed by in-loop filter when the luma in-loop filter indication indicates that in-loop filter processing is applied to the luma component. An additional flag may be used to indicate whether the in-loop filter processing is applied to an entire picture using same in-loop filter information or each block of the picture using individual in-loop filter information. Various embodiments according to the present invention to increase efficiency are disclosed, wherein various aspects of in-loop filter information are taken into consideration for efficient coding such as the property of quadtree-based partition, boundary conditions of a block, in-loop filter information sharing between luma and chroma components, indexing to a set of in-loop filter information, and prediction of in-loop filter information. | 11-22-2012 |
20130003843 | Motion Prediction Method - The invention provides a motion prediction method First, a coding unit (CU) of a current picture is processed, wherein the CU comprises at least a first prediction unit (PU) and a second PU. A second candidate set comprising a plurality of motion parameter candidates for the second PU is then determined, wherein at least a motion parameter candidate in the second candidate set is derive from a motion parameter predictor for a previously coded PU of the current picture, and the second candidate set is different from a first candidate set comprising a plurality of motion parameter candidates for the first PU. A motion parameter candidate is then selected from the second candidate set as a motion parameter predictor for the second PU. Finally, predicted samples are then generated from the motion parameter predictor of the second PU partition. | 01-03-2013 |
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 |
20130094568 | Method and Apparatus for In-Loop Filtering - A method and apparatus for in-loop processing of reconstructed video are disclosed. The reconstructed video data is partitioned into image units. The image unit corresponds to a Largest Coding Unit (LCU), a slice, or a tile. Horizontal deblocking is applied to the reconstructed video data across vertical image-unit boundaries and then vertical deblocking operates on n pixels of horizontal-deblocked video data on each side of horizontal image-unit boundaries. According to various embodiments of the present invention, the horizontal deblocking is applied to at least one of said n reconstructed lines to generate at least a horizontal-deblocked line for line p | 04-18-2013 |
20130128986 | Method and Apparatus of Slice Boundary Padding for Loop Filtering - A method and apparatus for video processing of reconstructed video in a reconstruction loop are disclosed. An embodiment according to the present invention performs padding for the blocks in the slice boundaries according to a processing order. Each of the one or more reconstructed blocks at slice boundaries is padded according to a padding order. In-loop filtering is applied to the reconstructed slice according to the processing order, wherein the reconstructed slice is filtered by referencing the one or more padded blocks. The padding order can be vertical-edge first and then horizontal-edge, or horizontal-edge first and then vertical-edge. Various embodiments are disclosed regarding whether padding for a later padded block in the processing order is skipped or not in the overlapped area. The present invention is also applied to adaptation blocks for block-based in-loop filtering in slice boundaries. | 05-23-2013 |
20130215959 | Method of Filter-Unit Based In-Loop Filtering - Methods for filter-unit based in-loop filtering in a video decoder and encoder are disclosed. In one embodiment, filter parameters are selected from a filter parameter set for each filter based on a filter index. In another embodiment, the picture is partitioned into filter units according to filter unit size, which can be selected between a default size and other size. When other size is selected, the filter unit size may be conveyed using direct size information or ratio information. In another embodiment, a merge flag and a merge index are used to convey filter unit merge information. A method for filter-unit based in-loop filtering in a video encoder for color video is disclosed. In one embodiment, the method incorporates filter syntax in the video bitstream by interleaving the color-component filter syntax for the FUs. | 08-22-2013 |
20130243098 | METHOD AND APPARATUS FOR DERIVATION OF MOTION VECTOR CANDIDATE AND MOTION VECTOR PREDICTION CANDIDATE - An apparatus and method for deriving a motion vector predictor are disclosed. A search set comprising of multiple (spatial, or temporal) search MVs with priority is determined, wherein the search MVs for multiple neighboring reference block or one or more co-located reference blocks arc configured into multiple search MV groups. In order to improve coding efficiency, embodiments according to the present invention, perform redundancy check every time after a search MV group is searched to determine whether an available search MV found. If an available search MV is found and the available search MV is not the same as a previously derived motion vector predictor (MVP), the available search MV is used as the MVP and the MVP derivation process terminates. Otherwise, the MVP derivation process moves to the next reference block. The search MV group can be configured to include different search MV(s) associated with reference blocks. | 09-19-2013 |
20130259117 | Method and Apparatus of Adaptive Loop Filtering - A method and apparatus for processing of coded video using adaptive offset (AO) are disclosed. Embodiments of the present invention divide reconstructed video data into multiple filter units and apply adaptive offset to the filter units to generate filtered video data, where boundaries of filter units correspond to boundaries of coding units and each of said filter units contains at least one coding unit. Furthermore, two or more of the multiple filter units can be merged as indicated by a merge index to share the applied adaptive offset. A filter control flag can be used to indicate filter ON/OFF control. The luma and chroma components may also share the same filter information. In another embodiment, the filter information sharing among filter units can be applied regardless whether the boundaries of the filter units are aligned with the boundaries of the coding units. | 10-03-2013 |
20130322523 | METHOD AND APPARATUS FOR REDUCTION OF IN-LOOP FILTER BUFFER - A method and apparatus for in-loop processing of reconstructed video are disclosed. The method and apparatus configure the in-loop processing so that the processing requires no pixel or reduced pixels from other side of a virtual boundary. When the in-loop processing of the to-be-processed pixel requires a pixel from the other side of the virtual boundary, the pixel from the other side of the virtual boundary is replaced by a replacement pixel. The in-loop processing can also be configured to skip the pixel when the processing requires a pixel from other side of the virtual boundary. The in-loop processing can also be configured to change ALF filter shape or filter size when the in-loop processing requires a pixel from other side of the virtual boundary. A filtered output can be combined linearly or nonlinearly with the to-be-processed pixel to generate a final filter output. | 12-05-2013 |
20130329784 | Method and Apparatus for Line Buffer Reduction for Video Processing - A method and apparatus of line buffer reduction for context adaptive entropy processing are disclosed. The context formation for context adaptive entropy processing depends on block information associated with one or more neighboring Determining context formation for processing a blocks. When the neighboring block is on a different current syntax element of a current block in a region, side of a region boundary from the current block, the wherein the context formation depends on block block information is replaced by replacement block information associated with a neighboring block information to reduce or remove line buffer requirement for storing the block information of neighboring blocks on the other side of the region boundaries from the current block. The context adaptive entropy Replacing the block information associated with a processing is CABAC encoding, CABAC decoding, neighboring block by replacement block information if CAVLC encoding, or CAVLC decoding. | 12-12-2013 |
20140003495 | Method and Apparatus of Scalable Video Coding | 01-02-2014 |
20140072033 | Method and Apparatus of Scalable Video Coding - A method and apparatus for scalable video coding are disclosed, wherein the video data is configured into a Base Layer (BL) and an Enhancement Layer (EL) and wherein the EL has higher spatial resolution or better video quality than the BL. According to embodiments of the present invention, information from the base layer is exploited for coding the enhancement layer. The information coding for the enhancement layer includes CU structure, motion information, motion information, MVP/merge candidates, intra prediction mode, residual quadtree information, texture information, residual information, context adaptive entropy coding, Adaptive Lop Filter (ALF), Sample Adaptive Offset (SAO), and deblocking filter. | 03-13-2014 |
20140078254 | Method and Apparatus of Motion and Disparity Vector Prediction and Compensation for 3D Video Coding - A method and apparatus for deriving MV/MVP (motion vector or motion vector predictor) or DV/DVP (disparity vector or disparity vector predictor) associated Skip mode, Merge mode or Inter mode for a block of a current picture in three-dimensional (3D) video coding are disclosed. The 3D video coding may use temporal prediction and inter-view prediction to exploit temporal and inter-view correlation. MV/DV prediction is applied to reduce bitrate associated with MV/DV coding. The MV/MVP or DV/DVP for a block is derived from spatial candidates, temporal candidates and inter-view candidates. For the inter-view candidate, the position of the inter-view co-located block can be located using a global disparity vector (GDV) or warping the current block onto the co-located picture according to the depth information. The candidate can also be derived as the vector corresponding to warping the current block onto the co-located picture according to the depth information. | 03-20-2014 |
20140085416 | METHOD AND APPARATUS OF TEXTURE IMAGE COMPRESS IN 3D VIDEO CODING - A method and apparatus for texture image compression in a 3D video coding system are disclosed. Embodiments according to the present invention derive depth information related to a depth map associated with a texture image and then process the texture image based on the depth information derived. The invention can be applied to the encoder side as well as the decoder side. The encoding order or decoding order for the depth maps and the texture images can be based on block-wise interleaving or picture-wise interleaving. One aspect of the present invent is related to partitioning of the texture image based on depth information of the depth map. Another aspect of the present invention is related to motion vector or motion vector predictor processing based on the depth information. | 03-27-2014 |
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 |
20140086502 | METHOD AND APPARATUS OF CHROMA INTRA PREDICTION WITH REDUCED LINE MEMORY - A method and apparatus for chroma intra prediction for a current chroma block with reduced line memory requirement are disclosed. The chroma intra predictor is derived from reconstructed luma pixels of a current luma block using a model with parameters. In various embodiments according to the present invention, the derivation of the parameters relies on a reconstructed luma pixel set corresponding to neighboring reconstructed luma pixels from causal luma neighboring areas of the current luma block, wherein said causal luma neighboring areas include a first area corresponding to reconstructed luma pixels above a horizontal luma block boundary on a top side of the current luma block, and wherein the reconstructed luma pixels from the first area that are included in the reconstructed luma pixel set are from a luma pixel line immediately above the horizontal luma block boundary. | 03-27-2014 |
20140092981 | METHOD AND APPARATUS FOR REMOVING REDUNDANCY IN MOTION VECTOR PREDICTORS - A method and apparatus of deriving a motion vector predictor (MVP) for a current block in an Inter, Merge, or Skip mode are disclosed. Embodiments according to the present invention determine redundant MVP candidates according to a non-MV-value based criterion. The redundant MVP candidates are then removed from the MVP candidate set. In other embodiments according to the present invention, motion IDs are assigned to MVP candidates to follow the trail of motion vectors associated with the MVP candidate. An MVP candidate having a same motion ID as a previous MVP is redundant and can be removed from the MVP candidate set. In yet another embodiment, redundant MVP candidates correspond to one or more of the MVP candidates that cause the second 2N×N or N×2N PU to be merged into a 2N×2N PU are removed from the MVP candidate set. | 04-03-2014 |
20140146891 | Method and Apparatus of Scalable Video Coding - A method and apparatus for scalable video coding are disclosed, wherein the video data is configured into a Base Layer (BL) and an Enhancement Layer (EL) and wherein the EL has higher spatial resolution or better video quality than the BL. According to embodiments of the present invention, information from the base layer is exploited for coding the enhancement layer. The information coding for the enhancement layer includes CU structure, motion information, motion information, MVP/merge candidates, intra prediction mode, residual quadtree information, texture information, residual information, context adaptive entropy coding, Adaptive Lop Filter (ALF), Sample Adaptive Offset (SAO), and deblocking filter. | 05-29-2014 |
20140169478 | METHOD AND APPARATUS OF DEBLOCKING FILTER WITH SIMPLIFIED BOUNDARY STRENGTH DECISION - A method and apparatus for deblocking of reconstructed video in a video coding system are disclosed. Embodiments according to the present invention determine boundary strength between two blocks without checking whether the block boundary is a coding unit (CU) boundary. In one embodiment according to the present invention, the method comprises determining whether any of the two blocks is Intra coded. If any of the two blocks is Intra coded, the boundary strength is assigned a first value. Otherwise, additional decision processing is performed to determine the boundary strength. In another embodiment, said determining the boundary strength for the block boundary comprises determining whether the block boundary is a TU boundary and whether any of the two blocks contains coefficients. In yet another embodiment, said determining the boundary strength for the block boundary comprises determining whether the two blocks have different reference pictures or different motion vectors. | 06-19-2014 |
20140192861 | METHOD AND APPARATUS FOR REORDERED BINARIZATION OF SYNTAX ELEMENTS IN CABAC - A method and apparatus of context-based adaptive binary arithmetic encoding/decoding for syntax elements of one or more blocks are disclosed. According to one embodiment of the present invention, the binarization results of the x and y positions of the last significant coefficient of a transform unit are reordered by collecting the bypass bins together. According to another embodiment of the present invention, binarization results of syntax elements from two or more of four Intra N×N prediction units, including prev_intra_luma_pred_flag, rem_intra_luma_pred_mode, and mpm_idx are reordered by collecting the bypass bins together. In yet another embodiment according to the present invention, the binarization results of other syntax elements are also reordered by collecting bypass bins together. Furthermore, the above reordering of binarization results may be used for binarization results corresponding to a block and its neighboring blocks. | 07-10-2014 |
20140198840 | METHOD AND APPARATUS FOR ADAPTIVE LOOP FILTER WITH CONSTRAINED FILTER COEFFICIENTS - Methods and apparatuses for processing of coded video using ALF are disclosed. Embodiments according to the present invention apply ALF with constrained data range to reconstructed video data. The ALF parameters comprise a center coefficient, one or more non-center coefficients, and an offset term. As an example, the constrained data range for the center coefficient is selected from [0.0, 2.0) and [0.5, 1.5). In another example, the constrained data range for said one or more non-center coefficient is selected from [−1.0, 1.0) and [−0.5, 0.5). The constrained data range can also be applied to the offset term. For example the range of [−2 | 07-17-2014 |
20140198844 | METHOD AND APPARATUS FOR NON-CROSS-TILE LOOP FILTERING - A method and apparatus for loop filter processing of video data are disclosed. Embodiments according to the present invention eliminate data dependency associated with loop processing across tile boundaries. According to one embodiment, loop processing is reconfigured to eliminate data dependency across tile boundaries if cross-tile loop processing is disabled. The loop filter processing corresponds to DF (deblocking filter), SAO (Sample Adaptive Offset) processing or ALF (Adaptive Loop Filter) processing. The processing can be skipped for at least one tile boundary. In another embodiment, data padding based on the pixels of the current tile or modifying pixel classification footprint are used to eliminate data dependency across the tile boundary. Whether cross-tile loop processing is disabled can be indicated by a flag coded at sequence, picture, or slice level to indicate whether the data dependency across said at least one tile boundary is allowed. | 07-17-2014 |
20140211848 | METHOD AND APPARATUS FOR REDUCTION OF DEBLOCKING FILTER - A method and apparatus for deblocking of reconstructed video are disclosed. In one embodiment, the method divides a block boundary into two sub-boundaries and separates lines or column across the sub-boundaries into two groups. The deblocking filter decision for each group is determined based on the lines or columns in the respective group. In another embodiment, the method divides block edges of blocks in the LCUs into two edge groups, where the first edge group corresponds to horizontal block edges between two LCUs and the second edge group corresponds to remaining block edges not included in the first edge group. The number of lines processed by a vertical filter in the first edge group is less than the number of lines processed by a vertical filter in the second edge group. Accordingly, a system embodying the present invention has reduced storage requirement. | 07-31-2014 |
20140219357 | METHOD AND APPARATUS FOR DERIVATION OF MOTION VECTOR PREDICTOR CANDIDATE SET - A method and apparatus for deriving a motion vector predictor (MVP) candidate set for a block are disclosed. Embodiments according to the present invention generate a complete full MVP candidate set based on the redundancy-removed MVP candidate set if one or more redundant MVP candidates exist. In one embodiment, the method generates the complete full MVP candidate set by adding replacement MVP candidates to the redundancy-removed MVP candidate set and a value corresponding to a non-redundant MVP is assigned to each replacement MVP candidate. In another embodiment, the method generates the complete full MVP candidate set by adding replacement MVP candidates to the redundancy-removed MVP candidate set and a value is as signed to each replacement MVP candidate according to a rule. The procedure of assigning value, checking redundancy, removing redundant MVP candidate are repeated until the MVP candidate set is complete and full. | 08-07-2014 |
20140241434 | METHOD AND APPARATUS OF MOTION AND DISPARITY VECTOR DERIVATION FOR 3D VIDEO CODING AND HEVC - A method and apparatus for deriving MVP (motion vector predictor) for a block for three-dimensional video coding or multi-view video coding are disclosed. Embodiments according to the present invention replace an unavailable inter-view MV of one neighboring block with a disparity vector derived from depth data of a subset of a depth block corresponding to one neighboring block. A method and apparatus for generating additional candidates for motion vector prediction associated with Merge mode or AMVP (Inter) mode for a block are disclosed. Embodiments according to the present invention generate one or more additional MVP candidates to add to the MVP list if the MVP list size is less than a given list size. The additional MVP candidates are generated either by reducing precision of an available MVP in the MVP list or by adding an offset to the available MVP in the MVP list. | 08-28-2014 |
20140247884 | METHOD AND APPARATUS FOR MV SCALING WITH INCREASED EFFECTIVE SCALING RATIO - A method and apparatus for deriving a scaled MV (motion vector) for a current block based on a candidate MV associated with a candidate block are disclosed. Embodiments according to the present invention increase effective scaling factor of motion vector scaling. In one embodiment, a distance ratio of a first picture distance between a current picture and a target reference picture pointed to by a current motion vector of the current block to a second picture distance between a candidate picture corresponding to the candidate block and a candidate reference picture pointed to by the candidate MV is computed. The scaled MV is then generated based on the candidate MV according to the distance ratio, where the scaled MV has an effective scaling ratio between −m and n, and wherein m and n are positive integers greater than 4. The values of m and n can be 8, 16 or 32. | 09-04-2014 |
20150016506 | METHOD AND APPARATUS FOR LOOP FILTERING ACROSS SLICE OR TILE BOUNDARIES - A method and apparatus for loop filter processing of video data in a video encoder or decoder are disclosed. Embodiments according to the present invention conditionally allow sharing of loop filter parameters. In one embodiment, sharing of loop filter information between the current block and a neighboring block is determined according to a condition. If the condition indicates that sharing of loop filter information is allowed, a merge flag is coded and incorporated in the video bitstream in an encoder, and a merge flag is parsed from the video bitstream and decoded in a decoder. In one embodiment, the condition depends on region partitioning of the picture, where region partitioning partitions the picture into regions and the region may correspond to a slice or a tile. The condition is set to indicate that sharing of loop filter information is allowed if the block and the neighboring block are in a same slice/tile. | 01-15-2015 |
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 |
20150085932 | METHOD AND APPARATUS OF MOTION VECTOR DERIVATION FOR 3D VIDEO CODING - A method and apparatus for deriving MVP (motion vector predictor) for Skip or Merge mode in 3D video coding are disclosed. In one embodiment, the method comprises determining an MVP candidate set for a selected block and selecting one MVP from an MVP list for motion vector coding of the block. The MVP candidate set may comprise multiple spatial MVP candidates associated with neighboring blocks and one inter-view candidate, and the MVP list is selected from the MVP candidate set. The MVP list may consist of only one MVP candidate or multiple MVP candidates. If only one MVP candidate is used, there is no need to incorporate an MVP index associated with the MVP candidate in the video bitstream corresponding to the three-dimensional video coding. Also, the MVP candidate can be the first available MVP candidate from the MVP candidate set according to a pre-defined order. | 03-26-2015 |