Abstract: Innovations in the area of prediction of block vector (“BV”) values improve encoding or decoding of blocks using intra block copy (“BC”) prediction. For example, some of the innovations relate to use of a default BV predictor with a non-zero value. Other innovations relate to use of a selected one of multiple BV predictor candidates for a current block. Still other innovations relate to use of a skip mode in which a current intra-BC-predicted block uses a predicted BV value.

Abstract: In an implementation, a supplemental sequence parameter set (“SPS”) structure is provided that has its own network abstraction layer (“NAL”) unit type and allows transmission of layer-dependent parameters for non-base layers in an SVC environment. The supplemental SPS structure also may be used for view information in an MVC environment. In a general aspect, a structure is provided that includes (1) information (1410) from an SPS NAL unit, the information describing a parameter for use in decoding a first-layer encoding of a sequence of images, and (2) information (1420) from a supplemental SPS NAL unit having a different structure than the SPS NAL unit, and the information from the supplemental SPS NAL unit describing a parameter for use in decoding a second-layer encoding of the sequence of images. Associated methods and apparatuses are provided on the encoder and decoder sides, as well as for the signal.

Abstract: Innovations in the area of prediction of block vector (“BV”) values improve encoding or decoding of blocks using intra block copy (“BC”) prediction. For example, some of the innovations relate to use of a default BV predictor with a non-zero value. Other innovations relate to use of a selected one of multiple BV predictor candidates for a current block. Still other innovations relate to use of a skip mode in which a current intra-BC-predicted block uses a predicted BV value.

Abstract: There are provided methods and apparatus for video usability information (VUI) for scalable video coding (SVC). An apparatus includes an encoder (100) for encoding video signal data into a bitstream. The encoder specifies video user information, excluding hypothetical reference decoder parameters, in the bitstream using a high level syntax element. The video user information corresponds to a set of interoperability points in the bitstream relating to scalable video coding (340, 355).

Abstract: There are provided methods and apparatus for video usability information (VUI) for scalable video coding (SVC). An apparatus includes an encoder (100) for encoding video signal data into a bitstream. The encoder specifies video user information, excluding hypothetical reference decoder parameters, in the bitstream using a high level syntax element. The video user information corresponds to a set of interoperability points in the bitstream relating to scalable video coding (340, 355).

Abstract: Innovations in intra block copy (“BC”) prediction as well as innovations in encoder-side search patterns and approaches to partitioning. For example, some of the innovations relate to use of asymmetric partitions for intra BC prediction. Other innovations relate to search patterns or approaches that an encoder uses during block vector estimation (for intra BC prediction) or motion estimation. Still other innovations relate to uses of BV search ranges that have a horizontal or vertical bias during BV estimation.

Abstract: Innovations in video playback using a browser-based video decoder are described. In a computer system that includes multiple central processing units (“CPUs”), a browser-based video decoder performs operations with multiple threads that may execute simultaneously on different CPUs. The video decoder can perform decoding operations in parallel for different sections of a picture. For example, with a main CPU thread associated with a browser, the video decoder performs a first decoding workload (e.g., bitstream parsing) for a picture. With auxiliary CPU threads associated with Web workers and simultaneously executing on different CPUs, the video decoder performs a second decoding workload (e.g., entropy decoding, decoding of side information) for different sections of the picture, one section per auxiliary CPU thread. If the computer system also includes a graphics processing unit (“GPU”), the video decoder can perform additional decoding workloads with shader routines executable on the GPU.

Abstract: Innovations in syntax and semantics of coded picture buffer removal delay (“CPBRD”) values potentially simplify splicing operations. For example, a video encoder sets a CPBRD value for a current picture that indicates an increment value relative to a nominal coded picture buffer removal time of a preceding picture in decoding order, regardless of whether the preceding picture has a buffering period SEI message. The encoder can signal the CPBRD value according to a single-value approach in which a flag indicates how to interpret the CPBRD value, according to a two-value approach in which another CPBRD value (having a different interpretation) is also signaled, or according to a two-value approach that uses a flag and a delta value. A corresponding video decoder receives and parses the CPBRD value for the current picture. A splicing tool can perform simple concatenation operations to splice bitstreams using the CPBRD value for the current picture.

Abstract: Innovations in motion estimation adapted for screen remoting scenarios are described. For example, a video encoder calculates a hash value for a current block in a current picture. The video encoder searches, subject to a spatial constraint, for a matching block in a reference picture (e.g., the previous picture in display order) based at least in part on the hash value for the current block. The spatial constraint defines a search area in the reference picture within which hash values for candidate blocks in the reference picture may be compared to the hash value for the current block. By using a spatial constraint to limit the range of the local hash-based motion estimation, the video encoder can speed up the motion estimation process while still considering the candidate blocks in the reference picture that are most likely to match the current block.

Abstract: Innovations in syntax and semantics of coded picture buffer removal delay (“CPBRD”) values potentially simplify splicing operations. For example, a video encoder sets a CPBRD value for a current picture that indicates an increment value relative to a nominal coded picture buffer removal time of a preceding picture in decoding order, regardless of whether the preceding picture has a buffering period SEI message. The encoder can signal the CPBRD value according to a single-value approach in which a flag indicates how to interpret the CPBRD value, according to a two-value approach in which another CPBRD value (having a different interpretation) is also signaled, or according to a two-value approach that uses a flag and a delta value. A corresponding video decoder receives and parses the CPBRD value for the current picture. A splicing tool can perform simple concatenation operations to splice bitstreams using the CPBRD value for the current picture.

Abstract: In an implementation, a supplemental sequence parameter set (“SPS”) structure is provided that has its own network abstraction layer (“NAL”) unit type and allows transmission of layer-dependent parameters for non-base layers in an SVC environment. The supplemental SPS structure also may be used for view information in an MVC environment. In a general aspect, a structure is provided that includes (1) information (1410) from an SPS NAL unit, the information describing a parameter for use in decoding a first-layer encoding of a sequence of images, and (2) information (1420) from a supplemental SPS NAL unit having a different structure than the SPS NAL unit, and the information from the supplemental SPS NAL unit describing a parameter for use in decoding a second-layer encoding of the sequence of images. Associated methods and apparatuses are provided on the encoder and decoder sides, as well as for the signal.

Abstract: There are provided methods and apparatus for video usability information (VUI) for scalable video coding (SVC). An apparatus includes an encoder (100) for encoding video signal data into a bitstream. The encoder specifies video user information, excluding hypothetical reference decoder parameters, in the bitstream using a high level syntax element. The video user information corresponds to a set of interoperability points in the bitstream relating to scalable video coding (340, 355).

Abstract: There are provided methods and apparatus for video usability information (VUI) for scalable video coding (SVC). An apparatus includes an encoder (100) for encoding video signal data into a bitstream. The encoder specifies video user information, excluding hypothetical reference decoder parameters, in the bitstream using a high level syntax element. The video user information corresponds to a set of interoperability points in the bitstream relating to scalable video coding (340, 355).

Abstract: In an implementation, a supplemental sequence parameter set (“SPS”) structure is provided that has its own network abstraction layer (“NAL”) unit type and allows transmission of layer-dependent parameters for non-base layers in an SVC environment. The supplemental SPS structure also may be used for view information in an MVC environment. In a general aspect, a structure is provided that includes (1) information (1410) from an SPS NAL unit, the information describing a parameter for use in decoding a first-layer encoding of a sequence of images, and (2) information (1420) from a supplemental SPS NAL unit having a different structure than the SPS NAL unit, and the information from the supplemental SPS NAL unit describing a parameter for use in decoding a second-layer encoding of the sequence of images. Associated methods and apparatuses are provided on the encoder and decoder sides, as well as for the signal.

Abstract: Syntax structures that indicate the completion of coded regions of pictures are described. For example, a syntax structure in an elementary bitstream indicates the completion of a coded region of a picture. The syntax structure can be a type of network abstraction layer unit, a type of supplemental enhancement information message or another syntax structure. For example, a media processing tool such as an encoder can detect completion of a coded region of a picture, then output, in a predefined order in an elementary bitstream, syntax structure(s) that contain the coded region as well as a different syntax structure that indicates the completion of the coded region. Another media processing tool such as a decoder can receive, in a predefined order in an elementary bitstream, syntax structure(s) that contain a coded region of a picture as well as a different syntax structure that indicates the completion of the coded region.

Abstract: Innovations in the area of prediction of block vector (“BV”) values improve encoding or decoding of blocks using intra block copy (“BC”) prediction. For example, some of the innovations relate to use of a default BV predictor with a non-zero value. Other innovations relate to use of a selected one of multiple BV predictor candidates for a current block. Still other innovations relate to use of a skip mode in which a current intra-BC-predicted block uses a predicted BV value.

Abstract: There are provided methods and apparatus for video usability information (VUI) for scalable video coding (SVC). An apparatus includes an encoder (100) for encoding video signal data into a bitstream. The encoder specifies video user information, excluding hypothetical reference decoder parameters, in the bitstream using a high level syntax element. The video user information corresponds to a set of interoperability points in the bitstream relating to scalable video coding (340, 355).

Abstract: Innovations in video decoding and rendering operations in a graphics pipeline, in which at least some of the operations are performed using a graphics processing unit (“GPU”), are described. For example, a video playback tool aggregates texture values for intra-coded blocks of a picture in central processing unit (“CPU”) memory, then transfers the texture values for the intra-coded blocks from the CPU memory to GPU memory. The video playback tool performs operations to decode the encoded data and reconstruct the picture. For a given block (e.g., of a macroblock, coding unit) of the picture, a graphics primitive represents texture values for the given block as a point for processing by the GPU. The video playback tool uses one or more shader routines, executable by the GPU, to transfer texture values to a display buffer. In some cases, the video playback tool also performs decoding operations with the shader routines.

Abstract: Video frames of a higher-resolution chroma sampling format such as YUV 4:4:4 are packed into video frames of a lower-resolution chroma sampling format such as YUV 4:2:0 for purposes of video encoding. For example, sample values for a frame in YUV 4:4:4 format are packed into two frames in YUV 4:2:0 format. After decoding, the video frames of the lower-resolution chroma sampling format can be unpacked to reconstruct the video frames of the higher-resolution chroma sampling format. In this way, available encoders and decoders operating at the lower-resolution chroma sampling format can be used, while still retaining higher resolution chroma information. In example implementations, frames in YUV 4:4:4 format are packed into frames in YUV 4:2:0 format such that geometric correspondence is maintained between Y, U and V components for the frames in YUV 4:2:0 format.

Abstract: There are provided methods and apparatus for video usability information (VUI) for scalable video coding (SVC). An apparatus includes an encoder (100) for encoding video signal data into a bitstream. The encoder specifies video user information, excluding hypothetical reference decoder parameters, in the bitstream using a high level syntax element. The video user information corresponds to a set of interoperability points in the bitstream relating to scalable video coding (340, 355).