Patent application number | Description | Published |
20080219578 | METHOD AND APPARATUS FOR CONTEXT ADAPTIVE BINARY ARITHMETIC CODING AND DECODING - A method of and apparatus for context adaptive binary arithmetic coding and decoding of a significance map indicating the position of a coefficient that is not zero in a residual block are provided. According to the method and apparatus, a subdivided context is selected according to whether or not a coefficient of a previous residual block corresponding to a coefficient of a current residual block, and binary arithmetic coding is performed according to the selected context, thereby improving the performance of context-based binary arithmetic coding. | 09-11-2008 |
20080232706 | METHOD AND APPARATUS FOR ENCODING AND DECODING IMAGE USING PIXEL-BASED CONTEXT MODEL - A method and apparatus for encoding and decoding an image are provided. The method includes selecting a context model by referring to previously encoded pixels that are adjacent to the current pixel for entropy-encoding a binary value of a pixel value of the current pixel, and entropy-encoding the binary value using the selected context model, thereby performing entropy-coding with high compression efficiency. | 09-25-2008 |
20090147843 | METHOD AND APPARATUS FOR QUANTIZATION, AND METHOD AND APPARATUS FOR INVERSE QUANTIZATION - Provided are a quantization method and apparatus and an inverse-quantization method and apparatus for determining quantization steps using lengths of runs that are transform coefficients having consecutive zero values and modifying the transform coefficients. The quantization apparatus can modify quantization steps so that the quantization steps are proportional to lengths of previous runs to quantize significant transform coefficients. As a result, a number of bits generated during coding can be reduced without a great deterioration of video quality. | 06-11-2009 |
20090207913 | METHOD AND APPARATUS FOR ENCODING AND DECODING IMAGE - Provided are methods and apparatuses for encoding an image and methods and apparatuses for decoding an image. The methods and apparatuses generate a compensated prediction block by compensating a prediction block of a current block by using a predetermined compensation value and encode a residual value that is a difference between the compensated prediction block and an input current block. | 08-20-2009 |
20090232204 | METHOD AND APPARATUS FOR ENCODING AND DECODING TRANSFORM COEFFICIENTS - A method of encoding transform coefficients and a transform coefficient encoding apparatus, and a method of decoding transform coefficients and a transform coefficient decoding apparatus are provided. The method of encoding the transform coefficients includes reading transform coefficients in a current block, determining whether a first transform coefficient having an absolute value greater than a predetermined threshold value exists in the transform coefficients in the current block, generating first flag information indicating whether the first transform coefficient exists, dividing the first transform coefficient from information of a second transform coefficient that is remaining transform coefficients excluding the first transform coefficient, and encoding the first transform coefficients and the second transform coefficients separately, thereby more efficiently using a correlation between each of the transform coefficients. | 09-17-2009 |
20090232211 | METHOD AND APPARATUS FOR ENCODING/DECODING IMAGE BASED ON INTRA PREDICTION - Provided is an intra prediction-based encoding method, and an apparatus for accomplishing the same. In the method, an order of scanning sub blocks divided from a current block is determined based on an edge present in the current block; a predicted block is generated by performing intra prediction on the current block in the order of scanning, based on already encoded blocks adjacent to the current block; and a residual block that is a difference between the current block and the predicted block is encoded. Accordingly, the precision of intra prediction can be improved, thus increasing the quality of an image. | 09-17-2009 |
20110110432 | METHOD AND APPARATUS FOR EFFECTIVELY COMPRESSING MOTION VECTORS IN VIDEO CODER BASED ON MULTI-LAYER - A method and apparatus of improving the compression efficiency of a motion vector by efficiently predicting a motion vector in an enhancement layer from a motion vector in a base layer in a video coding method using a multi-layer are provided. The method includes obtaining a motion vector in a base layer frame having a first frame rate from an input frame, obtaining a motion vector in a first enhancement layer frame having a second frame rate from the input frame, the second frame rate being greater than the first frame rate, generating a predicted motion vector by referring to a motion vector for at least one frame among base layer frames present immediately before and after the same temporal position as the first enhancement layer frame if there is no base layer frame at the same temporal position as the first enhancement layer frame, and coding a difference between the motion vector in the first enhancement layer frame and the generated predicted motion vector, and the obtained motion vector in the base layer. | 05-12-2011 |
20120008684 | METHOD AND APPARATUS OF ENCODING AND DECODING VIDEO SIGNAL - Provided are methods and apparatuses for encoding and decoding a video including a plurality of color components. The method of encoding includes: splitting a first color component block and neighboring pixels of the first color component block into N segments, where N is an integer, based on pixel values of the first color component block which have been previously encoded and then restored; splitting a second color component block, corresponding to the first color component block, and neighboring pixels of the second color component block into N segments according to the N segments of the first color component block and the neighboring pixels of the first color component block; predicting the N segments of the second color component block by using the neighboring pixels of the second color component block split into the N segments; and encoding the second color component block, based on a result of the prediction. | 01-12-2012 |
20120189061 | METHOD AND APPARATUS FOR EFFECTIVELY COMPRESSING MOTION VECTORS IN VIDEO CODER BASED ON MULTI-LAYER - A method and apparatus of improving the compression efficiency of a motion vector is provided. The method includes obtaining a motion vector in a base layer frame having a first frame rate from an input frame, obtaining a motion vector in a first enhancement layer frame having a second frame rate from the input frame, the second frame rate being greater than the first frame rate, generating a predicted motion vector by referring to a motion vector for at least one frame among base layer frames present immediately before and after the same temporal position as the first enhancement layer frame if there is no base layer frame at the same temporal position as the first enhancement layer frame, and coding a difference between the motion vector in the first enhancement layer frame and the generated predicted motion vector, and the obtained motion vector in the base layer. | 07-26-2012 |
20130114731 | METHOD AND APPARATUS FOR ENTROPY ENCODING/DECODING A TRANSFORM COEFFICIENT - A method and apparatus for entropy coding and decoding a transformation block are provided. The method of entropy coding a transformation block includes: | 05-09-2013 |
20130156111 | METHOD AND APPARATUS FOR ENCODING VIDEO USING ADJUSTABLE LOOP FILTERING, AND METHOD AND APPARATUS FOR DECODING VIDEO USING ADJUSTABLE LOOP FILTERING - Provided is a method of decoding a video by using a video decoding processor, the method including: extracting encoding information and encoded video data by receiving and parsing a bit stream of a video; decoding the encoded video data for each coding unit which is a data unit for decoding the video data, by using the encoding information; performing loop filtering on the coding unit with respect to the decoded video data by using internal pixels of the coding unit based on a minimum distance between a pixel on which loop filtering is to be performed and a border of the coding unit; and restoring the video by combining the decoded video data and data on which the loop filtering is performed, for each coding unit. | 06-20-2013 |