摘要:
Provided are encoding and decoding methods and apparatuses for a video by selectively determining and using a scan mode. The video encoding method includes: generating transformation coefficients by performing transformation based on a transformation unit to encode an image; determining a scan mode, from among a plurality of scan modes, indicating a scanning direction of the generated transformation coefficients, based on characteristics of the transformation coefficients; and determining and outputting an encoding order of the generated transformation coefficients based on the scanning direction of the determined scan mode.
摘要:
An apparatus and method for intra-predicting an image are provided. The method includes: obtaining, based on restored neighboring pixels of a chrominance block and restored neighboring pixels of a luminance pixel corresponding to the chrominance block, parameters representing a correlation between the chrominance block that is to be intra-predicted and a luminance block; and predicting, using the parameters, the chrominance block from the luminance block, wherein the obtaining the parameters includes performing a predetermined operation on the restored neighboring pixels of the chrominance block and the restored neighboring pixels of the luminance block, and wherein the predetermined operation comprises an adaptive scaling process of changing bit depths of the parameters to reduce a size of a look-up table and prevent an occurrence of overflow.
摘要:
A filtering method and apparatus for adaptively performing deblocking filtering are provided. The method includes: obtaining a parameter indicating how close pixel values of pixels adjacent to a block boundary are with respect to a predetermined line; determining a filtering strength at the block boundary based on the parameter; and performing filtering based on the filtering strength.
摘要:
Encoding and decoding an image may be performed by setting a plurality of segments of a second color component block based on pixel values of a first color component block. The plurality of segments may be predicted by using different context pixels, and the second color component block may be encoded and decoded based on the predicted plurality of segments.
摘要:
A method of encoding an image by transforming a group of prediction units into a frequency domain. A prediction unit may be predicted by using prediction values of the prediction units in the group of prediction units, instead of pixels generated by encoding and then restoring the other prediction units in the group of prediction units. Thus, an encoding compression ratio may be increased as a result of grouping the prediction units.
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:
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:
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 video encoding and decoding methods and apparatuses. The video encoding method includes: encoding a video based on data units having a hierarchical structure; determining a context model used for entropy encoding a syntax element of a data unit based on at least one piece of additional information of the data units; and entropy encoding the syntax element by using the determined context model.
摘要:
An encoding method using a skip mode is provided. The method includes obtaining a plurality of motion information candidates of a current predictor by using at least one predictor which relates to the current predictor; determining a candidate that is most likely to be selected from among the obtained plurality of motion information candidates as a most probable prediction candidate, based on a predetermined standard; and when a prediction mode of the current predictor corresponds to a most probable skip mode when using the determined most probable prediction candidate, encoding a flag which indicates the most probable skip mode.