Abstract: A method, computer program product, and computer system for processing video frames. A current frame is divided into M blocks that include at least two differently sized blocks. M is at least 9. Each block in the current frame is classified as being a motion block or an I-BLOCK. Overlapped block motion compensation (OBMC) is performed on each block of the M blocks according to a predetermined scan order. The block on which OBMC is being performed is denoted as a self block. The OBMC is performed on the self block with respect to its neighbor blocks. The neighbor blocks consist of nearest neighbor blocks of the self block. Performing OBMC on the self block includes generating a weighting window for the self block and for each of its neighbor blocks.

Abstract: Error detecting and protection innovations for video decoders are described. For example, in a multithreaded video decoder, a picture extent discovery (PED) task detects an error in a video bitstream which corrupts a picture. The PED task then determines any PED sub-stage which have been completed for the picture, and based on this determination, performs error-handing PED operations. In another example, an entropy decoding (ED) task checks validity on a macroblock-by-macroblock basis using a redundant buffer to avoid overflows. Additionally, error recovery innovations are described which facilitate playback of a video bit stream at an arbitrary position. For example, a video decoder chooses a picture in the bit stream after the arbitrary position at which to begin decoding based on a determination of acceptable recovery time and/or acceptable picture quality.

Abstract: Error concealment techniques for video decoding are described. For example, a video decoder after finding a corrupted picture in a bit stream, finds a suitable neighbor for the corrupted picture. For example, the video decoder favors pictures with the same parity as the corrupted picture and considers picture order count and picture corruption in choosing a neighbor. The decoder then modifies syntax elements for the encoded video in the bit stream to allow the neighbor to be used in concealing the corruption in the corrupted picture. The modification of syntax elements can depend on the particular video decoder implementation. For example, in a software-only multithreaded video decoder, a task graph is modified, while in a system utilizing video acceleration, syntax elements for reference lists are modified.

Abstract: A method, system, computer program product, and computer system for processing video frames. Frames A and B of a pair of successive video frames each comprise blocks of pixels. Frame A is earlier in time than frame B. A connection state of each pixel in frame B relative to the pixels of frame A is determined. The connection state is a connected state or an unconnected state. Each block in frame B is classified as either unconnected or uni-connected. Uni-connected blocks in frame B satisfying a reclassification criteria are reclassified as being unconnected. Each unconnected block in frame B is categorized as being a P-block or an I-block. Values for the pixels of each I-block in frame B are calculated by spatial interpolation based on values of nearest available neighbor pixels relative to each I-block. A residual error block for each I-block in frame B is generated.

Abstract: A decoder which can detect errors in MPEG-2 coefficient blocks can identify syntactically-correct blocks which have out-of-bounds coefficients. The decoder computes coefficient bounds based on quantization scalers and quantization matrices and compares these to coefficient blocks during decoding; if a block has out-of-bounds coefficients, concealment is performed on the block. In a decoder implemented all in software, coefficient bounds checking is performed on iDCT coefficients against upper and lower bounds in a spatial domain. In a decoder which performs iDCT in hardware, DCT coefficients are compared to an upper energy bound.

Abstract: Video decoding innovations for multithreading implementations and graphics processor unit (“GPU”) implementations are described. For example, for multithreaded decoding, a decoder uses innovations in the areas of layered data structures, picture extent discovery, a picture command queue, and/or task scheduling for multithreading. Or, for a GPU implementation, a decoder uses innovations in the areas of inverse transforms, inverse quantization, fractional interpolation, intra prediction using waves, loop filtering using waves, memory usage and/or performance-adaptive loop filtering. Innovations are also described in the areas of error handling and recovery, determination of neighbor availability for operations such as context modeling and intra prediction, CABAC decoding, computation of collocated information for direct mode macroblocks in B slices, reduction of memory consumption, implementation of trick play modes, and picture dropping for quality adjustment.

Abstract: Video decoding innovations for multithreading implementations and graphics processor unit (“GPU”) implementations are described. For example, for multithreaded decoding, a decoder uses innovations in the areas of layered data structures, picture extent discovery, a picture command queue, and/or task scheduling for multithreading. Or, for a GPU implementation, a decoder uses innovations in the areas of inverse transforms, inverse quantization, fractional interpolation, intra prediction using waves, loop filtering using waves, memory usage and/or performance-adaptive loop filtering. Innovations are also described in the areas of error handling and recovery, determination of neighbor availability for operations such as context modeling and intra prediction, CABAC decoding, computation of collocated information for direct mode macroblocks in B slices, reduction of memory consumption, implementation of trick play modes, and picture dropping for quality adjustment.

Abstract: Video decoding innovations for multithreading implementations and graphics processor unit (“GPU”) implementations are described. For example, for multithreaded decoding, a decoder uses innovations in the areas of layered data structures, picture extent discovery, a picture command queue, and/or task scheduling for multithreading. Or, for a GPU implementation, a decoder uses innovations in the areas of inverse transforms, inverse quantization, fractional interpolation, intra prediction using waves, loop filtering using waves, memory usage and/or performance-adaptive loop filtering. Innovations are also described in the areas of error handling and recovery, determination of neighbor availability for operations such as context modeling and intra prediction, CABAC decoding, computation of collocated information for direct mode macroblocks in B slices, reduction of memory consumption, implementation of trick play modes, and picture dropping for quality adjustment.

Abstract: A method and apparatus for scalable coding of a motion vector generated during motion estimation, in which a generated motion vector field is separated into a base layer and an enhancement layer according to pixel accuracies to obtain a layered structure for a motion vector. In addition, the motion vector field has a layered structure including a base layer composed of motion vectors of blocks larger than or equal to a predetermined size and at least one enhancement layer composed of motion vectors of blocks smaller than a predetermined size.

Abstract: A method, computer program product, and computer system for processing video frames. A current frame is divided into M blocks that include at least two differently sized blocks. M is at least 9. Each block in the current frame is classified as being a motion block or an I-BLOCK. Overlapped block motion compensation (OBMC) is performed on each block of the M blocks according to a predetermined scan order. The block on which OBMC is being performed is denoted as a self block. The OBMC is performed on the self block with respect to its neighbor blocks. The neighbor blocks consist of nearest neighbor blocks of the self block. Performing OBMC on the self block includes generating a weighting window for the self block and for each of its neighbor blocks.

Abstract: The invention discloses a pilot-tone signal transmission method and a system thereof. The method includes that at transmitting end, converting physical characteristics of an original pilot-tone signal, and then transmitting the converted pilot-tone signal on an optical fiber; at receiving end, anti-converting physical characteristics of the pilot-tone signal extracted from the optical fiber to recover to the said original pilot-tone signal. The system includes a source device, a target device, an electro-optical converter, optical fibers, an optic-electronic converter, a signal-extracting device, a signal-converting device and a signal-anti-converting device. With the above technical scheme, the invention overcomes carrier/noise ratio limitation, provides better SN ratio performance, and can effectively recover the pilot-tone signal to its original form even the SN ratio condition is worse.

Abstract: A method, system, computer program product, and computer system for processing video frames. Frames A and B of a pair of successive video frames each comprise blocks of pixels. Frame A is earlier in time than frame B. A connection state of each pixel in frame B relative to the pixels of frame A is determined. The connection state is a connected state or an unconnected state. Each block in frame B is classified as either unconnected or uni-connected. Uni-connected blocks in frame B satisfying a reclassification criteria are reclassified as being unconnected. Each unconnected block in frame B is categorized as being a P-block or an I-block. Values for the pixels of each I-block in frame B are calculated by spatial interpolation based on values of nearest available neighbor pixels relative to each I-block. A residual error block for each I-block in frame B is generated.