摘要:
A hybrid intra-inter bi-predictive (or multi-predictive) coding mode allows both intraframe (intra) and interframe (inter) predictions to be combined together for hybrid-encoding a current macroblock or a subblock Bi-prediction may be used also in I-pictures, combining two intra predictions that use two different intra prediction directions. A video encoder processes data representing a two-dimensional video image which has been produced by a conventional commercially available video camera. The video encoder is adapted to select, for coding a current macroblock, between an intra encoding mode, an P-frame inter encoding mode, a B-frame bi-predictive inter mode, and a hybrid intra-inter bi-predictive encoding mode. A video decoder (800) receives and decodes a data stream that may contain a block/macroblock encoded in accordance with the hybrid intra-inter bi-predictive encoding mode.
摘要:
Simulation of film grain in an image can occur by compressing a video image, then transmitting compressed video together with a message containing at least one parameter indicative of the original film grain, to a decoder, and restoring the original grainy appearance of images by having the decoder simulating film grain based on the content of the film grain message. To improve efficiency, one or more parameters of film grain information undergo scaling in accordance with a target pixel block size for pixel blocks in the image. Such scaling allows for the use of conventional circuitry for performing block-based operations in connection with the film grain simulation.
摘要:
A hybrid intra-inter bi-predictive (or multi-predictive) coding mode allows both intraframe (intra) and interframe (inter) predictions to be combined together for hybrid-encoding a current macroblock or a subblock. Bi-prediction may be used also in I-pictures, combining two intra predictions that use two different intra prediction directions. A video encoder processes data representing a two-dimensional video image which has been produced by a conventional commercially available video camera. The video encoder is adapted to select, for coding a current macroblock, between an intra encoding mode, an P-frame inter encoding mode, a B-frame bi-predictive inter mode, and a hybrid intra-inter bi-predictive encoding mode. A video decoder receives and decodes a data stream that may contain a block/macroblock encoded in accordance with the hybrid intra-inter bi-predictive encoding mode.
摘要:
A video encoder and corresponding methods are provided for selecting the mode of a current macroblock of an inter-coded frame, including one or more of checking first modes for a subset of macroblock modes, selectively checking other modes in response to motion vector information of the checked first modes, and selecting the mode for the current macroblock in response to the checked modes; checking the macroblock mode of at least one neighboring macroblock, and selecting the mode for the current macroblock in response to the macroblock mode of the at least one checked neighboring macroblock; checking the cost of a subset of macroblock modes, further checking only intra-coded modes if the checked cost meets a preset criteria, and selecting the mode for the current macroblock in response to the checked modes; and adjusting an early-stopping threshold in response to checked macroblock modes, and selecting the mode for the current macroblock in response to the checked macroblock modes if the adjusted early-stopping threshold is met.
摘要:
An encoder, a decoder, and corresponding methods are provided for encoding and decoding video signal data for an image block. The encoder includes a quantizer for receiving transform coefficients for the image block, and for adaptively performing dead-zone quantization based on coefficient positions and coefficient distributions of the transform coefficients.
摘要:
A video decoder, a video decoding method, a video encoder and a video encoding method are disclosed. A video decoder for decoding a video bitstream for an image block includes a motion vector resolution reducer and a motion compensator. The motion vector resolution reducer is for receiving decoded high resolution motion vectors included in the video bitstream and for reducing an accuracy of the high resolution motion vectors to correspond to a low resolution. The motion compensator, in signal communication with the motion vector resolution reducer, is for forming a motion compensated high resolution prediction using the reduced accuracy motion vectors. The video encoder for encoding scalable video comprises a motion compensator for forming a motion compensated full resolution prediction and combining the motion compensated full resolution prediction from an image block to form a prediction residual. The prediction residual is downsampled to form a low resolution downsampled prediction residual and then coded.
摘要:
The addition of comfort noise to an image serves to hide compression artifacts. To facilitate comfort noise addition, supplemental information accompanying a video image contains at least one parameter that specifies an attribute regarding comfort noise. Typically, the supplemental information includes parameters that function to turn the comfort noise on and off, as well as to indicate the level of noise to add, based on the expected level of compression artifacts.
摘要:
A video encoder and corresponding method are described for enabling fast channel change of compressed video, where a video encoder for receiving input pictures and providing compressed stream data includes a normal encoding portion for receiving input pictures and providing normal stream data, a lower-quality encoding portion for receiving input pictures and providing channel change stream data, and a multiplexor in signal communication with each of the normal and lower-quality portions for receiving and combining the normal and channel change data streams.
摘要:
Individual pixels in an image block undergo blending with film grain from a film grain block randomly selected from among a pool of previously established film grain blocks in accordance with a luma characteristic of the image block. Prior to blending, the selected film grain block undergoes deblocking by a deblocking filter (28). Following blending, a clipper clips the individual pixels prior to display. The pool of film grain blocks is created by scaling a set of film grain patterns in accordance with at least one parameter of a film grain information message that accompanies the image block.
摘要:
A video decoder, and corresponding method are described for enabling fast channel change of compressed video, where a video decoder for receiving compressed stream data and providing decompressed video output includes a demultiplexor for receiving the compressed stream data and separating the normal stream and the channel change stream, a normal decoding portion in signal communication with the demultiplexor for selectably receiving the compressed normal and channel change streams, and providing decompressed video output, and a normal frame store in signal communication with the normal decoding portion for storing reference pictures.