摘要:
Various techniques and tools for encoding and decoding (e.g., in a video encoder/decoder) binary information (e.g., skipped macroblock information) are described. In some embodiments, the binary information is arranged in a bit plane, and the bit plane is coded at the picture/frame layer. The encoder and decoder process the binary information and, in some embodiments, switch coding modes. For example, the encoder and decoder use normal, row-skip, column-skip, or differential modes, or other and/or additional modes. In some embodiments, the encoder and decoder define a skipped macroblock as a predicted macroblock whose motion is equal to its causally predicted motion and which has zero residual error. In some embodiments, the encoder and decoder use a raw coding mode to allow for low-latency applications.
摘要:
A digital media content (e.g., image, video, audio, etc.) encoder/decoder employs a spatially varying parameter to condition the application of an overlap pre-process and post-process to adjacent transform block edges for the spatial-domain lapped transform. This conditional application of the lapped transform to sub-blocks of the digital media can be signaled on an edge, block, macro-block or other granularity. Further, a restriction on use of the conditional lapped transform based on a frame-level quantization or other bit-rate related parameter minimizes the signaling overhead impact at low bit-rates of coding.
摘要:
Techniques and tools for encoding and decoding video images (e.g., interlaced frames) are described. For example, a video encoder or decoder processes 4:1:1 format macroblocks comprising four 8×8 luminance blocks and four 4×8 chrominance blocks. In another aspect, fields in field-coded macroblocks are coded independently of one another (e.g., by sending encoded blocks in field order). Other aspects include DC/AC prediction techniques and motion vector prediction techniques for interlaced frames.
摘要:
A digital media content (e.g., image, video, audio, etc.) encoder/decoder employs a spatially varying parameter to condition the application of an overlap pre-process and post-process to adjacent transform block edges for the spatial-domain lapped transform. This conditional application of the lapped transform to sub-blocks of the digital media can be signaled on an edge, block, macro-block or other granularity. Further, a restriction on use of the conditional lapped transform based on a frame-level quantization or other bit-rate related parameter minimizes the signaling overhead impact at low bit-rates of coding.
摘要:
A video encoder/decoder implements a lapped transform by applying an overlap filter in the spatial or transform domains to transform blocks. For interlace frames whose alternating scan lines are temporally displaced, the encoder/decoder imposes a limitation on application of the overlap filter to exclude horizontal block edges between adjacent transform blocks. This limitation can be imposed in both implementations where the overlap transform is applied across all blocks of an image, as well as implementations in which the lapped transform is conditionally applied on a spatially varying basis across the image.
摘要:
An improved deblocking filter for a video encoder/decoder reduces the computation expense of evaluating deblocking conditions. The improved deblocking filter bases the decision to filter block edges on sampled statistics of edge presence and strength, and also uses information of the motion vector, coded block pattern and transform type.
摘要:
Various techniques and tools for encoding and decoding (e.g., in a video encoder/decoder) binary information (e.g., skipped macroblock information) are described. In some embodiments, the binary information is arranged in a bit plane, and the bit plane is coded at the picture/frame layer. The encoder and decoder process the binary information and, in some embodiments, switch coding modes. For example, the encoder and decoder use normal, row-skip, column-skip, or differential modes, or other and/or additional modes. In some embodiments, the encoder and decoder define a skipped macroblock as a predicted macroblock whose motion is equal to its causally predicted motion and which has zero residual error. In some embodiments, the encoder and decoder use a raw coding mode to allow for low-latency applications.
摘要:
A video encoder/decoder implements a lapped transform by applying an overlap filter in the spatial or transform domains to transform blocks. For interlace frames whose alternating scan lines are temporally displaced, the encoder/decoder imposes a limitation on application of the overlap filter to exclude horizontal block edges between adjacent transform blocks. This limitation can be imposed in both implementations where the overlap transform is applied across all blocks of an image, as well as implementations in which the lapped transform is conditionally applied on a spatially varying basis across the image.
摘要:
Techniques and tools for extended range variable length coding and decoding of differential motion vector information are described. For example, a video decoder determines whether or not to use an extended range variable length decoding mode. When the extended range variable length decoding mode is used, the decoder decodes a differential motion vector in the extended range variable length decoding mode. Otherwise, the decoder decodes the differential motion vector in a default range variable length decoding mode. A video encoder performs corresponding processing.
摘要:
A video encoder performs multi-resolution video coding. For example, the encoder adaptively changes frame sizes to reduce blocking artifacts at low bitrates. A video decoder performs corresponding multi-resolution decoding.