Abstract:
Systems and methods of filtering video data using a plurality of filters are disclosed. In an embodiment, a method includes receiving and decoding a plurality of filters embedded in a video data bitstream at a video decoder. The method includes selecting, based on information included in the video data bitstream, a particular filter of the plurality of filters. The method further includes applying the particular filter to at least a portion of decoded video data of the video data bitstream to produce filtered decoded video data.
Abstract:
Systems and techniques are provided for processing video data. For example, the systems and techniques can include obtaining a current picture of video data and obtaining reference pictures for the current picture from the video data. A merge mode candidate can be determined for the current picture. First and second motion vectors can be identified for the merge mode candidate. A motion vector search strategy can be selected for the merge mode candidate from a plurality of motion vector search strategies. The selected motion vector search strategy can be associated with one or more constraints corresponding to at least one of the first motion vector or the second motion vector. The selected motion vector search strategy can be used to determine refined motion vectors based on the first motion vector, the second motion vector, and the reference pictures. The merge mode candidate can be processed using the refined motion vectors.
Abstract:
An example device includes a memory and processing circuitry in communication with the memory. The processing circuitry of a device is configured to form a most probable mode (MPM) candidate list for a chroma block of the video data stored to the memory, such that the MPM candidate list includes one or more derived modes (DMs) associated with a luma block of the video data associated with the chroma block, and a plurality of luma prediction modes that can be used for coding luminance components of the video data. The processing circuitry is further configured to select a mode from the MPM candidate list, and to code the chroma block according to the mode selected from the MPM candidate list.
Abstract:
A method of decoding video data including receiving a bitstream that includes a sequence of bits that forms a representation of a coded picture of the video data, partitioning the coded picture of the video data into a plurality of blocks using three or more different partition structures, and reconstructing the plurality of blocks of the coded picture of the video data. Partitioning the coded picture of the video data may include partitioning the coded picture of the video data into the plurality of blocks using a plurality partition structures. In some embodiments, partitioning is constrained to, for example, reduce memory bandwidth in implementations of video decoders.
Abstract:
In general, techniques are described for reducing the space required to store rate distortion values when selecting from multiple, different prediction modes. A video coding device comprising a processor may perform the techniques. The processor may determine first and second sets of intra-prediction modes for a current block of video data. The first and second sets of intra-prediction modes may include less intra-prediction modes, collectively, than a total number of intra-prediction modes. The processor may compute an approximate cost for each intra-prediction mode included in the first and second sets of intra-prediction modes. The processor may store the approximate cost for each intra-prediction mode identified in the first and second sets of intra-prediction modes to a memory. The processor may perform intra-prediction to encode the current block using a mode identified in at least one of the first or second set.
Abstract:
This disclosure provides systems, devices, apparatus, and methods, including computer programs encoded on storage media, for truncation error signaling and adaptive dither for lossy bandwidth compression. A processor may perform a truncation process for data, where the data is associated with display processing, image processing, or the data processing, where the truncation process for the data results in truncated data. The processor may compute a set of truncation error values associated with the truncation process for the truncated data. The processor may generate a set of residual samples for the truncated data. The processor may generate a bitstream based on the set of residual samples for the truncated data and the set of truncation error values associated with the truncation process.
Abstract:
Provided are systems, methods, and computer-readable medium for encoding and decoding video data. In various examples, a coding device can include multiple luma QP and chroma QP relationship tables. In performing quantization or inverse quantization one video data being encoded or decoded, respectively, the coding device can select a table. The table can be selected based on, for example, a slice type, a prediction mode, and/or a luminance value, among other factors. The coding device can then use the luma QP value to look up a chroma QP value from the table. The luma QP and chroma QP values can then be used in quantization or inverse quantization.
Abstract:
A device for video decoding a current block of video data, the device including one or more processors configured to compute a horizontal component of a motion vector and to compute a vertical component of a motion vector in an affine model. The affine model may be a four-parameter affine model which includes two control point motion vectors, or a six-parameter affine model which includes three control point motion vectors. The horizontal and vertical components may include differences between control point motion vectors based on first-bit shift operations and second bit-shift operations.
Abstract:
Improved systems and methods related to decoder-side motion vector derivation (DMVD), for example, in applying one or more constraints to motion information, such as a MV derived by DMVD, and/or a MV difference between an initial MV and an MV derived by DMVD. These techniques may be applied to any of the existing video codecs, such as HEVC (High Efficiency Video Coding), and/or may be an efficient coding tool in any future video coding standards. In one example, the block size used for DMVD can be restricted. In another example, FRUC bilateral matching can be simplified by not searching outside reference blocks indicated by the original motion vector.
Abstract:
A method of decoding data indicative of a subset of transform coefficients is described. The coefficients are indicative of a block of video data. The method may include determining that no transform coefficient in the subset of transform coefficients has an absolute value greater than one, and, based on the determining, skipping one or more decoding passes on the subset of transform coefficients, the decoding passes relating to decoding level information associated with the subset of transform coefficients.