摘要:
A method of encoding flags, a method of decoding flags and an apparatus thereof, in which flag encoding and decoding can be efficiently performed by using spatial correlation between various flags included a plurality of blocks are provided. The method includes collecting flag values respectively allocated to groups of the plurality of blocks according to spatial correlation of blocks to create a flag bit-string, dividing the flag bit-string into a plurality of divided bit-strings using a group size, setting a pattern bit indicating whether all bits included in the divided bit-strings are 0 or not, and performing entropy coding on the divided bit-strings according to the set pattern bit.
摘要:
A method and apparatus for encoding and decoding an image by performing motion prediction and compensation on pictures in a group of pictures by selectively using a high-quality key picture that is previously encoded and restored, and a second picture that is previously encoded and restored. The method of encoding an image improves the prediction efficiency of an image by storing a key picture, which is encoded and restored to a high quality by reducing a loss caused by a quantization error using a small quantization coefficient, in a first storage unit and storing a previously encoded and restored second picture in a second storage unit, and then performing motion prediction and compensation by selectively using the key picture stored in the first storage unit and the second picture stored in the second storage unit while encoding a next picture in a group of pictures.
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:
The present invention relates to a video compression technology, and more particularly, to an effective flag-coding method and apparatus thereof by using a spatial correlation among various flags used to code a video frame. In order to accomplish the object, there is provided an apparatus for encoding a flag used to code a video frame composed of a plurality of blocks, the apparatus including a flag-assembling unit which collects flag values allotted for each block and produces a flag bit string, based on spatial correlation of the blocks, a maximum-run-determining unit which determines a maximum run of the flag bit string, and a converting unit which converts the bits included in the flag bit string into a codeword having a size no more than the maximum run by using a predetermined codeword table.
摘要:
Provided is a method and apparatus for encoding a video by using dynamic range transformation based on content and a method and apparatus for decoding a video by using dynamic range transformation based on content. The encoding method includes: performing inter prediction, through motion estimation, and intra prediction for a current region using image data in which a dynamic range of the current region is transformed based on content of an image of input video; performing transformation on residual data generated by the intra prediction and the inter prediction and performing quantization on a transformation coefficient generated by the transformation; and performing entropy encoding on the quantized transformation coefficient.
摘要:
Provided are methods and apparatuses for encoding and decoding a motion vector. The method of encoding a motion vector includes: selecting a mode from among a first mode in which information indicating a motion vector predictor of at least one motion vector predictor is encoded and a second mode in which information indicating generation of a motion vector predictor based on pixels included in a previously encoded area adjacent to a current block is encoded; determining a motion vector predictor of the current block according to the selected mode and encoding information about the motion vector predictor of the current block; and encoding a difference vector between a motion vector of the current block and the motion vector predictor of the current block.
摘要:
A method and apparatus for encoding a skip macroblock by dividing the skip macroblock into smaller skip sub blocks and using predictive motion vectors predicted from motion vectors of blocks adjacent to the skip sub blocks, and a method and apparatus for decoding the skip macroblock is provided. Accordingly, by adding predetermined binary information indicating whether the skip macroblock is divided to the skip macroblock that generally transmits only prediction mode information, division of the skip macroblock can be adaptively applied, or all skip macroblocks can be divided into sub-blocks to be processed, so that pixel values in the skip macroblock can be predicted by using motion vectors of spatially adjacent blocks. Therefore, prediction efficiency increases.
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:
A method and apparatus for encoding and decoding an image by performing motion prediction and compensation on pictures in a group of pictures by selectively using a high-quality key picture that is previously encoded and restored, and a second picture that is previously encoded and restored. The method of encoding an image improves the prediction efficiency of an image by storing a key picture, which is encoded and restored to a high quality by reducing a loss caused by a quantization error using a small quantization coefficient, in a first storage unit and storing a previously encoded and restored second picture in a second storage unit, and then performing motion prediction and compensation by selectively using the key picture stored in the first storage unit and the second picture stored in the second storage unit while encoding a next picture in a group of pictures.
摘要:
Provided are a method and apparatus for encoding an image by using sub-pixel-based motion prediction and a method and apparatus for decoding an image by using sub-pixel-based motion prediction. The method of encoding an image includes determining weights for respective low-precision sub-pixels for interpolation between the low-precision sub-pixels, determining an interpolation direction for the low-precision sub-pixels based on a position of a high-precision sub-pixel between the low-precision sub-pixels, and performing motion prediction in units of high-precision sub-pixels determined by interpolation which applies the interpolation direction and the weights to the low-precision sub-pixels.