摘要:
A scalable video encoding method and apparatus based on a plurality of layers are provided. The video encoding method for encoding a video sequence having a plurality of layers includes coding a residual of a first block existing in a first layer among the plurality of layers; recording the coded residual of the first block on a non-discardable region of a bitstream, if a second block is coded using the first block, the second block existing in a second layer among the plurality of layers and corresponding to the first block; and recording the coded residual of the first block on a discardable region of the bitstream, if a second block is coded without using the first block.
摘要:
A dequantization method and an apparatus in which restored values for original values are obtained by dequantizing quantization level values generated when the original values are quantized. The dequantization method includes updating a histogram by accumulating histogram counts for the quantization level values, estimating a distribution function of the original values based on the histogram, and obtaining the restored values for the quantization level values from the distribution function.
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 are provided for performing entropy encoding on a fine granular scalability layer. A method of entropy encoding on a plurality of current coefficients of a quality layer among a plurality of quality layers of an image block divided into the plurality of quality layers, includes determining a coding pass with respect to each of the current coefficients, selecting a context model with respect to each of the current coefficients using at least one lower coefficient corresponding to each of the current coefficients if the coding pass is a refinement pass, and performing arithmetic encoding a group of coefficients having a same selected context model among the current coefficients by using the selected context model.
摘要:
An image interpolation method and apparatus are provided. The image interpolation method includes: selecting different interpolation filters according to locations of sub pixels between integer pixels; and generating sub pixel values at the locations of the sub pixels using the selected interpolation filters.
摘要:
An image filtering method and apparatus that filter a block of a plane area by using a pseudo-random filter are provided, whereby artifacts generated in image encoding and decoding procedures are removed, the method including: determining a similarity between pixel values of a the first block; and generating a second block by selectively applying a pseudo-random filter on the first block according to a result of based on the determining the determined similarity.
摘要:
Provided are a method and apparatus for encoding and decoding based on inter prediction. In the method of encoding based on inter prediction, image inpainting is performed by searching for at least one reference picture by using pixels that are adjacent to the boundary between a current block and a previously encoded region of a current picture and are included in the previously encoded region, and the current block is encoded based on a predicted block obtained as the result of performing image inpainting. Accordingly, it is possible to precisely generate a predicted block, thereby improving the compression rate of image encoding.
摘要:
A video encoding method and apparatus and a video decoding method and apparatus are provided. The video encoding method encodes residual values included in a residual block of a current block after sub-sampling or down-sampling the residual values, thereby encoding and decoding the current block using a small number of residual values and thus improving the compression rate of video encoding.
摘要:
A method of reducing a mismatch between an encoder and a decoder in motion compensated temporal filtering, and a video coding method and apparatus using the same. The video coding method includes dividing input frames into one final low-frequency frame and at least one high-frequency frame by performing motion compensated temporal filtering on the input frames; encoding the final low-frequency frame and decoding the encoded final low-frequency frame; re-estimating the at least one high-frequency frame using the decoded final low-frequency frame; and encoding the re-estimated high-frequency frame.
摘要:
Methods and apparatuses for encoding and decoding an image are provided. The method of encoding an image includes: replacing a transformation coefficient having a low frequency component to be predicted from among transformation coefficients of a transformation block with a predetermined value; generating an incomplete residual block by inversely transforming the transformation block including the replaced transformation coefficient; and predicting the transformation coefficient having the low frequency component by using values of the incomplete residual block.