摘要:
The present invention relates generally to multimedia, and more specifically, to a system and method of improved television viewing using automatic parallel recording of television channels. The invention continuously captures and records multimedia content for a set of “channels” in a central location, buffering all available channels for a number of days or weeks on a continuous basis. The buffered programming may then be streamed over a network such as the Internet on request, to the viewer's premises where it can be viewed on request via an appropriate display device such as a television equipped with an IP-enabled set top box or on a personal computer.
摘要:
In some embodiments, a video decoder is capable of recovering skipped video data (e.g. motion vectors, prediction modes, quantization parameters, selected frequency-domain coefficients such as DC and 5-lowest-frequency AC coefficients, and/or entire video data blocks) using multiple alternative recovery modes such as spatial interpolation, temporal interpolation, and motion search. To decide whether to skip a particular data type for a block, the encoder evaluates the effect of skipping the data on rate and distortion by simulating the decoder data recovery using the multiple recovery modes. The encoder transmits indicators of skipped data types and associated recovery modes, if different from decoder baselines. The skipped data and recovery mode indicators may be included in macroblock and/or slice headers, and/or as part of sequence, group-of-picture (GOP), or picture coding parameter data. Skipped data recovery decoder resources (e.g. motion search logic) may be used for recovering data lost due to transmission errors.
摘要:
An image and video enhancement technique is described that allows a core enhancement algorithm to be applied to images captured in various challenging lighting conditions. The technique detects a lighting impairment and inverts the image if it is a low-light impairment. The inverted low-light image is similar to haze impairment images, allowing both haze images and low-light images to be enhanced using the same enhancement algorithm.
摘要:
A method for encoding video, comprising the steps of (A) encoding a number of frames of a video signal using a first sub-set of encoding parameters, (B) analyzing the encoded frames to find and mark reference frames that are used more than a predetermined number of times, and (C) re-encoding the video signal using a second sub-set of encoding parameters different than the first sub-set of encoding parameters when re-encoding the marked reference frames.
摘要:
A motion vector prediction method in an error resilient mode. In the motion vector prediction method capable of decoding backwards, motion vectors of macro blocks are calculated, and motion vectors of macro blocks each having one motion vector are predicted while moving to another macro block from left to right, and motion vectors of macro blocks each having four motion vectors are continuously predicted in a predetermined sequence to have correlation in prediction of the four motion vectors. Thus, in the motion vector prediction method based on the image signal compression method of the MPEG-4 or H.263 standard, the motion vector prediction is performed with continuity and correlation among the motion vectors, so that two-way decoding is possible during transmission of blocks with a predetermined packet, resulting in better error resilient characteristics.
摘要:
The present invention is a method and system which extracts, manipulates and embeds data from a compressed and standard compliant video bitstream which may be used for digital rights management, e.g. controlling access to a bitstream or for authenticating a video bitstream.The method embeds binary data bits into compressed and standard compliant video bitstream with minimal visual artifacts. The method first parses the compressed video bitstream and locates coded blocks. The codeword C for the last triplet in the original block(RUNc,LEVELc, LASTc=1) is replaced by the VLC code word C′ for the last triplet (RUNC,LEVELC, LASTC′=0). A codeword corresponding to a triplet with LAST=1 is placed after C′ whose sign bit “s” can be either 0 or 1 and is an embedded data bit, and can be used for authentication.
摘要:
A method for performing entropy coding comprising the steps of (A) receiving an input stream and side information, (B) analyzing the side information to determine all constraints associated with the side information and (C) replacing the input stream with an index to a list of the number of valid input streams that satisfy all constraints associated with each specific type of the side information.
摘要:
A method and apparatus automatically manipulates a digitally compressed video bitstream such that the result is compatible with different bandwidth and error resilience requirements at a receiving point in a heterogeneous communication network. The method and device provide for analysis of bitstream header information to determine its relevant coding syntax parameters. Feedback from the receiving point on the network is then used to identify error robustness requirements for an intermediate bitstream. The bitstream is then manipulated by an error robustness regulator to achieve error protection in the network. The bitrate requirements of the network establish a selection of relevant and irrelevant bits from the bitstream The present method and device include identification of irrelevant and low priority video bits; intentional introduction of packet losses to reduce bitrate while maintaining visual quality; use of replacement tags for irrelevant and low priority components of the bitstream for compatible decoding by a wide array of decoders; and insertion of resynchronization tags and translation of predictively coded video packet bits for the improvement of error resilience.
摘要:
Video compression coding with partitioning of data into motion vector data and texture data with reversible Golomb-Rice type codes for the data. Resynchronization markers separate the data types, and the reversible coding permites decoding in both forward and backward directions to minimize data discarded due to errors.
摘要:
A congestion control mechanism for TCP communication sessions is described. The congestion control mechanism adjusts the size of the congestion window based on a number, N, of parallel virtual connections. The number N of parallel virtual connections used to determine the congestion window is dynamically adjusted based on an estimation of the network condition.