# Alexander Alshin, Suwon-Si KR

## Alexander Alshin, Suwon-Si KR

Patent application number | Description | Published |
---|---|---|

20090092330 | METHOD AND APPARATUS FOR CORRECTING QUANTIZED COEFFICIENTS IN DECODER - Provided are a method and apparatus for correcting quantized coefficients. In the method, statistical values of coefficients and quantized coefficients are extracted from a received video data stream, coefficient correction values for each pixel position in blocks are determined by using the statistical distribution of the coefficients depending on the statistical values, and then the coefficients are corrected by respectively adding the coefficient correction values to corresponding coefficients of respective pixel positions. | 04-09-2009 |

20090097768 | METHOD AND APPARATUS FOR ENCODING IMAGE BY EXPONENTIAL GOLOMB BINARIZATION USING OPTIMAL THRESHOLD, AND METHOD AND APPARATUS FOR DECODING IMAGE BY EXPONENTIAL GOLOMB BINARIZATION USING OPTIMAL THRESHOLD - A method and apparatus for coding an image by using exponential Golomb binarization are provided. The method comprises: performing entropy coding on an input image by performing exponential Golomb binarization using a plurality of predetermined thresholds; measuring a bit rate of a bit stream which is generated by performing the entropy coding using each threshold; and determining an optimal threshold by comparing bit rates with regard to the thresholds. | 04-16-2009 |

20090110317 | METHOD AND APPARATUS FOR COMPRESSING IMAGE SIGNAL - A method of compressing image signals, to provide more efficient compression than a discrete cosine transform (DCT) while having the least amount of overhead information is provided. A partial exchange between a row and a column of a transform matrix is performed by applying several values to a parameter, which shows an extent of partial exchange between rows and columns of the transform matrix. When a value of the used angle parameter is stored or transmitted, an overhead increases. Processes generating a random sequence of the angle parameter, generating a compression coefficient matrix regarding each angle parameter of the generated random sequence, and calculating a compression rate are repeated to obtain an angle parameter with the highest compression rate. The angle parameter having the highest compression rate is not stored or transmitted, but a number in the random sequence of the corresponding angle parameter is obtained, and stored or transmitted. | 04-30-2009 |

20100054619 | METHOD AND APPARATUS FOR INVERSE QUANTIZING IMAGE, AND METHOD AND APPARATUS FOR DECODING IMAGE - Provided are method and apparatus for inverse quantizing an image, the method including: determining a quantization step correction value for reducing a quantization error, which is a difference between an inverse quantization coefficient, obtained by inverse quantizing a quantization coefficient, and an original value of the transformation coefficient; and inverse quantizing the quantization coefficient using a second quantization step value, the second quantization step value being obtained by correcting a first quantization step value used for inverse quantizing the quantization coefficient using the determined quantization step correction value. | 03-04-2010 |

20110038555 | METHOD AND APPARATUS FOR ENCODING AND DECODING IMAGE BY USING ROTATIONAL TRANSFORM - A method and apparatus for encoding an image is provided. The method and apparatus include quantizing and entropy encoding a second frequency coefficient matrix that is generated by performing a partial exchange of one or more values between rows and between columns of a first frequency coefficient matrix. A method and apparatus for decoding image data that is encoded by using the method and apparatus for encoding the image is also provided. | 02-17-2011 |

20110097003 | METHOD AND APPARATUS FOR ENCODING AND DECODING IMAGE BY USING ROTATIONAL TRANSFORM - An image encoding method includes generating a first frequency coefficient matrix by transforming a predetermined block to a frequency domain; determining whether the first frequency coefficient matrix includes coefficients whose absolute values are greater than a predetermined value; generating a second frequency coefficient matrix by selectively partially switching at least one of rows and columns of the first frequency coefficient matrix according to an angle parameter based on a determination result; and selectively encoding the second frequency coefficient matrix based on the determination result. | 04-28-2011 |

20110103475 | IMAGE ENCODING METHOD AND DEVICE, AND DECODING METHOD AND DEVICE THEREFOR - A video encoding method and apparatus and a video decoding method and apparatus. In the video encoding method, a first predicted coding unit of a current coding unit that is to be encoded is produced, a second predicted coding unit is produced by changing a value of each pixel of the first predicted coding unit by using each pixel of the first predicted coding unit and at least one neighboring pixel of each pixel, and the difference between the current coding unit and the second predicted coding unit is encoded, thereby improving video prediction efficiency. | 05-05-2011 |

20110135000 | METHOD AND APPARATUS FOR ENCODING VIDEO, AND METHOD AND APPARATUS FOR DECODING VIDEO - Disclosed are a video encoding method and apparatus and a video decoding method and apparatus. The method of encoding video includes: producing a first predicted coding unit of a current coding unit, which is to be encoded; determining whether the current coding unit comprises a portion located outside a boundary of a current picture; and producing a second predicted coding unit is produced by changing a value of pixels of the first predicted coding unit by using the pixels of the first predicted coding unit and neighboring pixels of the pixels when the current coding unit does not include a portion located outside a boundary of the current picture. Accordingly, a residual block that is the difference between the current encoding unit and the second predicted encoding unit, can be encoded, thereby improving video prediction efficiency. | 06-09-2011 |

20110135212 | METHOD AND APPARATUS FOR ENCODING AND DECODING IMAGE BY USING ROTATIONAL TRANSFORM - Disclosed are a method and apparatus for encoding and decoding an image. The image encoding method includes: generating a first frequency coefficient matrix by performing spatial transform (e.g. discrete cosine transform (DCT) on a current block; determining an angle parameter based on whether the current block is intra or inter predicted; generating a second frequency coefficient matrix by performing a partial switch between at least one of rows and columns of the first frequency coefficient matrix based on the determined angle parameter; and encoding the second frequency coefficient matrix and information about the angle parameter. | 06-09-2011 |

20110243232 | METHOD AND APPARATUS FOR ENCODING VIDEO BY USING DYNAMIC-RANGE TRANSFORMATION, AND METHOD AND APPARATUS FOR DECODING VIDEO BY USING DYNAMIC-RANGE TRANSFORMATION - 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. | 10-06-2011 |

20110243233 | METHOD AND APPARATUS FOR ENCODING AND DECODING VIDEO - Methods and apparatuses for encoding and decoding video are provided. The encoding method includes: performing motion estimation on a current block according to a first sub-pixel unit, and obtaining a motion vector in the first sub-pixel unit with respect to the current block; interpolating a reference picture indicated by the motion vector according to a second sub-pixel unit smaller than the first sub-pixel unit; using the interpolated reference picture, selecting a second sub-pixel in the second sub-pixel unit adjacent to a first sub-pixel in the first sub-pixel unit of the reference picture; selecting a corresponding region that has a smaller error with the current block, from among a first corresponding region of the reference picture and obtained with respect to the first sub-pixel, and a second corresponding region of the current block and obtained with respect to the selected second sub-pixel; and encoding information of the selected corresponding region. | 10-06-2011 |

20110243248 | METHOD AND APPARATUS FOR ENCODING VIDEO BY COMPENSATING FOR PIXEL VALUE ACCORDING TO PIXEL GROUPS, AND METHOD AND APPARATUS FOR DECODING VIDEO BY THE SAME - Provided are a method and apparatus of encoding a video by compensating for a pixel value and a method and apparatus of decoding a video by compensating for a pixel value. The method of encoding the video includes: encoding image data; decoding the encoded image data and generating a restored image by performing loop filtering on the decoded image data; determining a compensation value corresponding to errors between a predetermined group restored pixels in the restored image and corresponding original pixels, and a pixel group including a restored pixel to be compensated for by using the compensation value; and encoding the compensation value and transmitting the encoded compensation value and a bitstream of the encoded image data. | 10-06-2011 |

20110243471 | METHOD AND APPARATUS FOR PERFORMING INTERPOLATION BASED ON TRANSFORM AND INVERSE TRANSFORM - 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. | 10-06-2011 |

20120147957 | IMAGE ENCODING METHOD AND DEVICE, AND DECODING METHOD AND DEVICE THEREFOR - A video encoding method and apparatus and a video decoding method and apparatus. In the video encoding method, a first predicted coding unit of a current coding unit that is to be encoded is produced, a second predicted coding unit is produced by changing a value of each pixel of the first predicted coding unit by using each pixel of the first predicted coding unit and at least one neighboring pixel of each pixel, and the difference between the current coding unit and the second predicted coding unit is encoded, thereby improving video prediction efficiency. | 06-14-2012 |

20120195379 | METHOD AND APPARATUS FOR ENCODING IMAGES, AND METHOD AND APPARATUS FOR DECODING ENCODED IMAGES - 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. | 08-02-2012 |

20130077682 | VIDEO ENCODING METHOD AND VIDEO ENCODING APPARATUS AND VIDEO DECODING METHOD AND VIDEO DECODING APPARATUS, WHICH PERFORM DEBLOCKING FILTERING BASED ON TREE-STRUCTURE ENCODING UNITS - A method of encoding a video is provided, the method includes: determining a filtering boundary on which deblocking filtering is to be performed based on at least one data unit from among a plurality of coding units that are hierarchically configured according to depths indicating a number of times at least one maximum coding unit is spatially spilt, and a plurality of prediction units and a plurality of transformation units respectively for prediction and transformation of the plurality of coding units, determining filtering strength at the filtering boundary based on a prediction mode of a coding unit to which pixels adjacent to the filtering belong from among the plurality of coding units, and transformation coefficient values of the pixels adjacent to the filtering boundary, and performing deblocking filtering on the filtering boundary based on the determined filtering strength. | 03-28-2013 |

20130083851 | METHOD AND APPARATUS FOR VIDEO ENCODING AND METHOD AND APPARATUS FOR VIDEO DECODING - Methods and apparatuses for encoding and decoding a video by using pixel unit bi-directional motion compensation are provided. According to the method of encoding a video, pixel unit motion compensation is performed on each pixel of a current block by using pixels of first and second reference pictures used for bi-directional motion prediction and compensation, in addition to block unit bi-directional motion compensation performed on the current block, and a bi-directional motion prediction value of the current block is generated by using results of the block unit bi-directional motion compensation and pixel unit motion compensation. | 04-04-2013 |

20130182780 | METHOD AND DEVICE FOR INTERPOLATING IMAGES BY USING A SMOOTHING INTERPOLATION FILTER - Provided are a method of interpolating an image by determining interpolation filter coefficients, and an apparatus for performing the same. The method includes: differently selecting an interpolation filter, from among interpolation filters for generating at least one sub-pel-unit pixel value located between integer-pel-unit pixels, based on a sub-pel-unit interpolation location and a smoothness; and generating the at least one sub-pel-unit pixel value by interpolating, using the selected interpolation filter, pixel values of the integer-pel-unit pixels. | 07-18-2013 |