摘要:
Intra prediction is used in state-of-the-art video coding standards such as AVC. The intra prediction modes are coded into the bitstream. Luma and chroma components could potentially have different prediction modes. For chroma components, there are 7 different modes defined in AVC: vertical, horizontal, DC, diagonal directions, and “same as luma”. Statistics show that the “same as luma” mode is frequently used, but in AVC, this mode is encoded using more bits than other modes during entropy coding, therefore the coding efficiency is decreased. Accordingly, a modified binarization/codeword assignment for chroma intra mode signaling is able to be utilized for high efficiency video coding (HEVC), the next generation video coding standard.
摘要:
Intra prediction is used in state-of-the-art video coding standards such as AVC. The intra prediction modes are coded into the bitstream. Luma and chroma components could potentially have different prediction modes. For chroma components, there are 7 different modes defined in AVC: vertical, horizontal, DC, diagonal directions, and “same as luma”. Statistics show that the “same as luma” mode is frequently used, but in AVC, this mode is encoded using more bits than other modes during entropy coding, therefore the coding efficiency is decreased. Accordingly, a modified binarization/codeword assignment for chroma intra mode signaling is able to be utilized for high efficiency video coding (HEVC), the next generation video coding standard.
摘要:
Motion Compensated Prediction (MCP) has been a key factor in most advanced video compression schemes. For further reduction in the residual signal energy in B-frames, bidirectional prediction where two motion-compensated signals are superimposed has also been utilized in most prior video coding standards such as MPEG-2 or MPEG-4/AVC. Syntax changes and appropriate motion vector prediction that allows efficient use of multi-parameter MCP is described. The prediction signal is constructed by linearly combining the motion-compensated signals from each parameter (or motion vector).
摘要:
A method of estimating motion by estimating motion parameters of a complex motion model using reconstructed neighboring pixels of the current block and then applying the estimated motion parameters to the coordinates of the current block to determine motion compensated in a corresponding reference block. The parameters are not transmitted to a decoder and are derived at the decoder side. The encoder only sends a 1-bit control-flag to indicate whether the derived parameters should be used.
摘要:
Motion Compensated Prediction (MCP) has been a key factor in most advanced video compression schemes. For further reduction in the residual signal energy in B-frames, bidirectional prediction where two motion-compensated signals are superimposed has also been utilized in most prior video coding standards such as MPEG-2 or MPEG-4/AVC. Syntax changes and appropriate motion vector prediction that allows efficient use of multi-parameter MCP is described. The prediction signal is constructed by linearly combining the motion-compensated signals from each parameter (or motion vector).
摘要:
A method of estimating motion by estimating motion parameters of a complex motion model using reconstructed neighboring pixels of the current block and then applying the estimated motion parameters to the coordinates of the current block to determine motion compensated in a corresponding reference block. The parameters are not transmitted to a decoder and are derived at the decoder side. The encoder only sends a 1-bit control-flag to indicate whether the derived parameters should be used.
摘要:
Spatial domain directional intra prediction has been shown to be very effective to remove the correlation between the pixels in the current block and reconstructed neighbors. In AVC, 8 directional prediction modes (plus the DC prediction mode) are defined. The prediction mode number is signaled to the decoder using a simple predictive coding method. The previous intra prediction methods have two major disadvantages: lack of precision for arbitrary directional patterns and accuracy lack of accuracy to exploit geometric dependency between blocks. To address these issues, a new method accurately predicts the intra directions from reconstructed neighboring pixels and differentially encode the intra directions. This allows a more precise directional prediction without the significant increase in the cost for transmitting the side information.
摘要:
Spatial domain directional intra prediction has been shown to be very effective to remove the correlation between the pixels in the current block and reconstructed neighbors. In AVC, 8 directional prediction modes (plus the DC prediction mode) are defined. The prediction mode number is signaled to the decoder using a simple predictive coding method. The previous intra prediction methods have two major disadvantages: lack of precision for arbitrary directional patterns and accuracy lack of accuracy to exploit geometric dependency between blocks. To address these issues, a new method accurately predicts the intra directions from reconstructed neighboring pixels and differentially encode the intra directions. This allows a more precise directional prediction without the significant increase in the cost for transmitting the side information.
摘要:
A parametric loop filter uses a set of fixed filters to remove or reduce noise and artifacts introduced during video coding. The filters are pre-trained offline and hardwired into encoder and decoder, instead of online trained Wiener filters. The filters are able to be specified using one or more parameters including: direction, bandwidth along the direction (bw//) and bandwidth perpendicular to the direction (bw⊥). The filter to be used is able to be derived from local image characteristics or predicted from neighboring blocks. The parametric loop filter utilizes much less computation, delay and memory access at the encoder. Fixed coefficients allow fast implementation of filtering at the decoder. A parametric loop filter is able to be combined with online training to further improve performance, by allowing one or more fixed filters to be replaced with online trained Wiener filters.
摘要:
A parametric loop filter uses a set of fixed filters to remove or reduce noise and artifacts introduced during video coding. The filters are pre-trained offline and hardwired into encoder and decoder, instead of online trained Wiener filters. The filters are able to be specified using one or more parameters including: direction, bandwidth along the direction (bw//) and bandwidth perpendicular to the direction (bw⊥). The filter to be used is able to be derived from local image characteristics or predicted from neighboring blocks. The parametric loop filter utilizes much less computation, delay and memory access at the encoder. Fixed coefficients allow fast implementation of filtering at the decoder. A parametric loop filter is able to be combined with online training to further improve performance, by allowing one or more fixed filters to be replaced with online trained Wiener filters.