摘要:
Disclosed is an adaptive transform method based on an in-screen prediction, and an apparatus using the method. A method for encoding an image can comprise a step of determining in-screen prediction mode groups, and a step of transforming by using a different transform method according to the in-screen prediction mode group. As a result, transforming can be performed by applying the different transform method according to the in-screen prediction mode group.
摘要:
A method and apparatus of improving the compression efficiency of a motion vector is provided. The method includes obtaining a motion vector in a base layer frame having a first frame rate from an input frame, obtaining a motion vector in a first enhancement layer frame having a second frame rate from the input frame, the second frame rate being greater than the first frame rate, generating a predicted motion vector by referring to a motion vector for at least one frame among base layer frames present immediately before and after the same temporal position as the first enhancement layer frame if there is no base layer frame at the same temporal position as the first enhancement layer frame, and coding a difference between the motion vector in the first enhancement layer frame and the generated predicted motion vector, and the obtained motion vector in the base layer.
摘要:
Provided is a method of decoding a video by using a video decoding processor, the method including: extracting encoding information and encoded video data by receiving and parsing a bit stream of a video; decoding the encoded video data for each coding unit which is a data unit for decoding the video data, by using the encoding information; performing loop filtering on the coding unit with respect to the decoded video data by using internal pixels of the coding unit based on a minimum distance between a pixel on which loop filtering is to be performed and a border of the coding unit; and restoring the video by combining the decoded video data and data on which the loop filtering is performed, for each coding unit.
摘要:
A method and apparatus for entropy coding and decoding a transformation block are provided. The method of entropy coding a transformation block includes:determining, according to a certain scan order, a location of a last significant transformation coefficient having a non-zero value from among transformation coefficients included in a transformation block having a certain size; and coding information about the determined location of the last significant transformation coefficient by using a horizontal axis direction location of the last significant transformation coefficient and a vertical axis direction location in the transformation block of the last significant transformation coefficient.
摘要:
Multi-layer video coding and decoding methods, multi-layer video encoder and multi-layer video decoder are provided. The multi-layer video coding method includes encoding a video frame having a predetermined resolution using a first video coding scheme, using a frame encoded by the first video coding scheme as a reference to encode the video frame with the same resolution as the predetermined resolution using a second video coding scheme, and generating a bitstream containing the frames encoded by the first and second video coding schemes.
摘要:
A method and apparatus for efficiently predecoding a hybrid bitstream generated by a plurality of coding schemes are provided. The method includes obtaining a first bit-rate for a boundary between the lower layer bitstream and the upper layer bitstream and a second bit-rate for a boundary between motion information and texture information of the upper layer bitstream from the input hybrid bitstream, determining the target bit-rate according to variable network circumstances, and when the target bit-rate is between the first and second bit-rates, skipping the motion information of the upper layer bitstream and truncating all bits of the texture information of the upper layer bitstream from the tail, except bits corresponding to the difference between the target bit-rate and the first bit-rate.
摘要:
A method and apparatus for enhancing the performance of entropy coding in a multilayer-based codec system are provided. In a variable length coding method for lossless-coding first coefficients among coefficients of a discrete layer and one or more fine granular scalability (FGS) layers, the variable length coding method includes determining a proportion of zeros included in a predetermined unit region to which the first coefficients belong, selecting one of a plurality of grouping units depending on whether or not the proportion exceeds a predetermined threshold, grouping absolute values of the first coefficients using the selected grouping unit, and transforming the grouped absolute values into a code word mapped thereto by referring to a VLC table corresponding to the selected group unit.
摘要:
An apparatus for enhancing the performance of entropy coding in a multilayer-based codec and an entropy coding method includes obtaining a distribution of a second coefficient included in an area of a base layer corresponding to the block, selecting a lookup table which is appropriate to the obtained distribution among a plurality of lookup tables, and transforming the first coefficient into a value mapped to the selected lookup table.
摘要:
A method and apparatus for encoding and decoding a fine granularity scalable (FGS) layer using reconstructed data of a lower layer. The method includes encoding the FGS layer in a multilayer video signal includes reconstructing original data of the lower layer that corresponds to a low-pass frame represented by the FGS layer, obtaining a residual between original data of the enhancement layer and the reconstructed original data of the lower layer, and generating an FGS layer bitstream through the processes of quantizing the residual and performing an entropy coding of the quantized residual.
摘要:
A method and apparatus for adaptively selecting a context model for entropy coding and a video decoder are provided. A method of coding a residual prediction flag indicating whether residual data for an enhancement layer block of a multi-layered video signal is predicted from residual data for a lower layer block corresponding to the residual data for the enhancement layer block includes the steps of calculating the energy of the residual data for the lower layer block, determining a coding method for the residual prediction flag according to the energy, and coding the residual prediction flag using the determined coding method.