摘要:
Disclosed are an image encoding method and apparatus for encoding an image by grouping a plurality of adjacent prediction units into a transformation unit and transforming the plurality of adjacent prediction into a frequency domain, and an image decoding method and apparatus for decoding an image encoded by using the image encoding method and apparatus.
摘要:
Provided are a method and apparatus for interpolating an image. The method includes: selecting a first filter, from among a plurality of different filters, for interpolating between pixel values of integer pixel units, according to an interpolation location; and generating at least one pixel value of at least one fractional pixel unit by interpolating between the pixel values of the integer pixel units by using the selected first filter.
摘要:
An image transformation method substitutes element based on a trigonometric function included in a discrete cosine transform (DCT) matrix with a rational number, performs upscaling and transformation process on an input signal using the substituted DCT matrix based on a maximum value of a denominator of an intermediate value generated in the transformation process, and performs downscaling on the transformed signal.
摘要:
Provided are a method and apparatus for transforming an image, in which an input image is transformed into a frequency domain by selectively using a plurality of frequency transform algorithms according to a frequency characteristic of the input image. The method includes: selecting a frequency transform algorithm to be used for a current block from a plurality of frequency transform algorithms according to a result obtained by transforming frequencies of peripheral blocks adjacent to the current block; and transforming the current block into a frequency domain by using the selected frequency transform algorithm.
摘要:
Provided are a method and apparatus for encoding and decoding at least one image frame artificially inserted by a user among a plurality of image frames of an image sequence by using a parameter regarding characteristics of the image frame.
摘要:
A motion vector compression apparatus includes: a down-sampling module for down-sampling an original frame to have a size of a frame in each layer; a motion vector search module for obtaining a motion vector in which an error or a cost function is minimized with respect to the down-sampled frame; a reference vector generation module for generating a reference motion vector in a predetermined enhanced layer by means of a block of a lower layer corresponding to a predetermined block in the predetermined enhanced layer, and motion vectors in blocks around the block; and a motion difference module for calculating a difference between the obtained motion vector and the reference motion vector.
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:
Provided are a method and apparatus for encoding and decoding based on intra prediction. In the method, information regarding a direction of intra prediction of a current block is encoded into one of a plurality of values, depending on whether the directions of intra prediction of neighboring blocks that have been encoded before encoding the current block are identical to one another and whether the direction of intra prediction of the current block is identical to those of the neighboring blocks. Accordingly, it is possible to increase the compression rate of intra prediction encoding with a higher probability.
摘要:
Provided are methods and apparatuses for encoding and decoding a motion vector. The method of encoding the motion vector includes: selecting, as a mode of encoding information about a motion vector predictor of the current block, a first mode in which information indicating the motion vector predictor from among at least one motion vector predictor is encoded or a second mode in which information indicating generation of the motion vector predictor based on blocks or pixels included in a previously encoded area adjacent to the current block is encoded; determining the motion vector predictor of the current block according to the selected mode and encoding the information about the motion vector predictor of the current block; and encoding a difference vector between the motion vector of the current block and the motion vector predictor of the current block.
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.