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:
Encoding and decoding video signals according to the characteristics of coefficients included in the block of a fine granularity scalability layer is provided. Non-unitary coefficients that constitute the block and have absolute values that are not 0 or 1 are extracted from the video signal, a representative value from run values of the extracted non-unitary coefficients is calculated, the run values of the coefficients constituting the block and the representative value are compared, and codewords are assigned to the coefficients according to a result of the comparison.
摘要:
An apparatus and method are provided for independently parsing fine granular scalability (FGS) layers. A video-encoding method according to an exemplary embodiment of the present invention includes a frame-encoding unit which generates at least one quality layer from an input video frame, a coding-pass-selecting unit which selects a coding pass according to a coefficient of a reference block spatially neighboring a current block in order to code a coefficient of the current block included in the quality layer, and a pass-coding unit which losslessly codes the coefficient of the current block according to the selected coding pass.
摘要:
A method of reducing mismatch between an encoder and a decoder in a motion compensated temporal filtering process and a video coding method and apparatus using the same. The video coding method includes the steps of dividing input frames into one final low-pass frame and at least one high-pass frame through a motion compensated temporal filtering, coding the final low-pass frame and then decoding the coded final low-pass frame, re-estimating the high-pass frame by using the decoded final low-pass frame, and coding the re-estimation high-pass frame.
摘要:
A method and apparatus for compressing a video/image using a region-of-interest (ROI), which allows only a particular region to be emphasized within a single frame during wavelet-based scalable video/image coding. The method includes generating wavelet coefficients by performing wavelet transform on an input image, rearranging the wavelet coefficients in wavelet blocks according to spatial relevancy among the wavelet coefficients, and quantizing the wavelet coefficients in each of the wavelet blocks. According to the method and apparatus, blocking artifacts occurring when an image is segmented into blocks and an ROI method is used can be remarkably decreased.
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 video signal on a group basis is disclosed, in which blocks constituting a multi-layer video signal are coded. The method includes grouping every two or more blocks having symbols that have a value identical to a predetermined value, generating group-based symbols each indicating information about the grouped blocks, and coding the group-based symbols.
摘要:
A method and apparatus for efficiently encoding diverse flags being used in a multilayer-based scalable video codec, based on an inter-layer correlation. The encoding method includes judging whether flags of a current layer included in a specified unit area are all equal to flags of a base layer, setting a specified prediction flag according to the result of judgment, and if it is judged that the flags of the current layer are equal to the flags of the base layer, skipping the flags of the current layer and inserting the flags of the base layer and the prediction flag into a bitstream.
摘要:
Methods and apparatuses for entropy encoding and decoding Fine-granularity Scalability (FGS) layer video data are provided. The encoding method includes extracting residual data between a first block and a second block in a layer lower than the FGS layer corresponding to the first block; obtaining transform coefficients; dividing the transform coefficients in the first block into at least two subblocks; calculating the length of a prefix of first coefficients in the subblocks; and combining the prefix with a suffix used to distinguish the first coefficients; and VLC encoding the first coefficients. The encoding apparatus includes a subblock divider, a prefix generator, and a significant coefficient encoding unit. The decoding method includes calculating a range of a transform coefficient using a length of a prefix of the transform coefficient; extracting a value of the transform coefficient; VLC decoding the value; and combining first and second subblocks having the decoded coefficients.
摘要:
A video coding method and apparatus are provided for improving compression efficiency or video/image quality by selecting a spatial transform method suitable for characteristics of an incoming video/image during video/image compression. The video coding apparatus includes a temporal transform module for removing temporal redundancy in an input frame to generate a residual frame, a wavelet transform module for performing wavelet transform on the residual frame to generate a wavelet coefficient, a Discrete Cosine Transform (DCT) module for performing DCT on the wavelet coefficient of each DCT block to create a DCT coefficient, and a quantization module for quantizing the DCT coefficient.