摘要:
A decoder and method for using a new picture or frame type is provided. This type is referred to a an SP-picture. The temporal redundancies are not exploited in I-frames, compression efficiency of I-frame coding is significantly lower than the predictive coding. A method allows use of motion compensated predictive coding to exploit temporal redundancy in the sequence while still allowing perfect reconstruction of the frame using different reference frames. Methods using this new picture type provide for error resilience/recovery, bandwidth scalability, bitstream switching, processing scalability, random access and other functions. The SP-type picture provides for, among other functions, switching between different bitstreams, random access, fast forward and fast error-recovery by replacing I-pictures to increase the coding efficiency. As will be demonstrated, SP-pictures have the property that identical SP-frames may be obtained even when they are predicted using different reference frames.
摘要:
A motion compensated video coding method which can be applied especially in transfer of video streams using low transmission bit rate is presented. In the motion compensated coding method, the motion of picture elements between a piece of reference video information and a piece of current video information is estimated and then modeled using certain basis function and coefficients. The coefficients are quantized, and the quantizer is selected according to a certain selection criterion, for example, based on a target image quality or on a target transmission bit rate. Preferably the selection criterion is such that it automatically adjust the accuracy with which the motion of picture elements is represented to be related to the accuracy with which the prediction error information is represented. A decoding method, an encoder and a corresponding decoder are also described.
摘要:
In one example, a device for coding video data includes a video coder configured to determine, for a depth block of a depth component of video data, a co-located texture block of a corresponding texture component, and when at least a portion of the texture block corresponds to a prediction unit of the texture component that is not intra-prediction coded: disable an inter-component Wedgelet depth modeling mode for the depth block, select an intra-prediction coding mode for the depth block other than the disabled inter-component Wedgelet depth modeling mode, and code the depth block using the selected intra-prediction coding mode.
摘要:
Aspects of this disclosure relate to a method of coding video data. In an example, the method includes determining a first residual quadtree (RQT) depth at which to apply a first transform to luma information associated with a block of video data, wherein the RQT represents a manner in which transforms are applied to luma information and chroma information. The method also includes determining a second RQT depth at which to apply a second transform to the chroma information associated with the block of video data, wherein the second RQT depth is different than the first RQT depth. The method also includes coding the luma information at the first RQT depth and the chroma information at the second RQT depth.
摘要:
In one example, an apparatus includes a processor configured to receive video data for two or more views of a scene, determine horizontal locations of camera perspectives for each of the two or more views, assign view identifiers to the two or more views such that the view identifiers correspond to the relative horizontal locations of the camera perspectives, form a representation comprising a subset of the two or more views, and, in response to a request from a client device, send information indicative of a maximum view identifier and a minimum view identifier for the representation to the client device.
摘要:
This disclosure includes techniques for signaling characteristics of a representation of multimedia content at a representation layer, such as frame packing arrangement information for the representation. In one example, an apparatus for receiving video data includes a processing unit configured to receive information indicative of whether a bitstream includes a packed frame of video data, wherein the packed frame comprises two frames corresponding to different views of a scene for three-dimensional playback, and wherein the information is present in a representation layer external to a codec layer of the bitstream, automatically determine whether the apparatus is capable of decoding and rendering the bitstream based on an analysis of the received information and decoding and rendering capabilities of the device, and retrieve the bitstream when the processing unit determines that the device is capable of decoding and rendering the bitstream.
摘要:
A video encoder determines that the last significant coefficient (LSC) of a transform coefficient block occurs at a given ordinal position according to a coding scanning order. The video encoder generates a coordinate indicator that specifies the coordinates of a given transform coefficient in the transform coefficient block. The given transform coefficient occurs at the same ordinal position according to an assumed scanning order. A video decoder receives the coordinate indicator and converts the coordinate indicator into a scan-based LSC indicator. The scan-based LSC indicator indicates the ordinal position of the LSC.
摘要:
The techniques of this disclosure apply to loop filtering across slice or tile boundaries in a video coding process. In one example, a method for performing loop filtering in a video coding process includes determining that pixels corresponding to filter coefficients of a filter mask for a loop filter are across a slice or tile boundary, removing filter coefficients corresponding to the pixels across the slice or tile boundary from the filter mask, renormalizing the filter mask without the removed filter coefficients, performing loop filtering using the renormalized filter mask.
摘要:
Disclosed are techniques for coding coefficients of a video block having a non-square shape defined by a width and a height, comprising coding one or more of x- and y-coordinates that indicate a position of a last non-zero coefficient within the block according to an associated scanning order, including coding each coordinate by determining one or more contexts used to code the coordinate based on one of the width and the height that corresponds to the coordinate, and coding the coordinate by performing a context adaptive entropy coding process based on the contexts. Also disclosed are techniques for coding information that identifies positions of non-zero coefficients within the block, including determining one or more contexts used to code the information based on one or more of the width and the height, and coding the information by performing a context adaptive entropy coding process based on the contexts.
摘要:
In one example, an apparatus for coding video data includes a video coder configured to determine a first prediction mode for a first block of video data and a second prediction mode for a second block of video data, wherein the first block and the second block share a common edge, decode the first block using the first prediction mode and the second block using the second prediction mode, and determine whether to deblock the common edge between the first block and the second block based at least in part on whether at least one of the first prediction mode and the second prediction mode comprises short distance intra-prediction (SDIP).