# Chang-Beom Ahn, Seoul KR

## Chang-Beom Ahn, Seoul KR

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

20090067503 | METHOD AND APPARATUS FOR VIDEO DATA ENCODING AND DECODING - Video data encoding and decoding methods and apparatuses are provided. In the video data encoding and decoding methods, codes books are provided to an encoder and a decoder. In the encoder, an index corresponding to a vector that is most similar to a current vector of an input moving picture among the vectors of the code book is encoded. In the decoder, the index is decoded. Accordingly, it is possible to increase compression ratio and reduce calculation complexity. | 03-12-2009 |

20090161759 | METHOD AND APPARATUS FOR VIDEO CODING ON PIXEL-WISE PREDICTION - Provided is a video encoding and decoding method and apparatus using pixel-based prediction. A pixel-based video encoding apparatus includes a block prediction unit, a residual image generation unit, a pixel prediction unit, and an entropy-coding unit. The block prediction unit performs temporal or spatial prediction between a reference image and a current image in order to generate a prediction block corresponding to a current block to be encoded. The residual image generation unit generates a residual image block composed of a residual signal corresponding to a difference between pixels of the prediction block and pixels of the current block. The pixel prediction unit determines whether to apply differential pulse coded modulation (DPCM) to each of pixels of the residual image block based on a rate distortion optimization (RDO) value calculated for the case where DPCM is applied to each of the pixels of the residual image block and a RDO value calculated for the case where DPCM is not applied to each of the pixels of the residual image block. The entropy-coding unit performs entropy-coding on the residual image block. | 06-25-2009 |

20090201992 | METHOD AND APPARATUS FOR ENCODING AND DECODING HOPPING DEFAULT VIEW FOR MULTIPLE CAMERAS SYSTEM - Provided is a multiple camera system, and more particularly, a method and apparatus for processing hopping default views in an apparatus for encoding/decoding video streams of multiple view positions. The encoding apparatus for the multiple camera system includes an encoder for receiving video signals of multiple view positions, and encoding the video signals based on a predetermined default Group of Pictures (GoP); a default GoP selector for providing the default GoP information to the encoder; and a multiplexer for multiplexing the encoded video signals and sequentially outputting only the default GoP. | 08-13-2009 |

20090238271 | APPARATUS AND METHOD FOR ENCODING AND DECODING USING ALTERNATIVE CONVERTER ACCODING TO THE CORRELATION OF RESIDUAL SIGNAL - Provided is an apparatus and method for encoding and decoding using alternative transform units according to the correlation of residual signals. The video encoding apparatus includes a first transforming unit for performing discrete cosine transform (DCT), first quantization, first inverse quantization, and inverse DCT on a block basis onto residual coefficients generated after intra frame prediction or inter frame prediction; a second transforming unit for performing discrete sine transform (DST), second quantization, second inverse quantization, and inverse DST on a block basis onto the residual coefficients; a selecting unit for selecting one having a high compression rate between the first and second transforming units for each block through performing rate-distortion optimization; and a flag marking unit for recording information about the selected transforming unit at a flag bit provided on a macroblock basis. | 09-24-2009 |

20100046613 | MULTI-DIMENSIONAL AND MULTI-STAGE TRANSFORMING APPARATUS AND METHOD - Provided are an apparatus for multi-stage transforming a plurality of unit blocks in multi-dimension that can improve compression efficiency of video data by collecting Discrete Cosine Transforming (DCT) coefficients of neighboring blocks and performing an additional transformation based on the DCT coefficients of an original picture and a differential picture. The method includes the steps of: performing a Discrete Cosine Transform (DCT) on inputted picture data and selecting R blocks of a predetermined size from DCT picture data, where R is a natural number equal to or greater than 2; arranging DCT coefficients of each of the selected R blocks according to each frequency in one-dimension; and performing one-dimensional transformation again on the DCT coefficients arranged in one-dimension. | 02-25-2010 |

20100094638 | APPARATUS AND METHOD FOR DECIDING ADAPTIVE NOISE LEVEL FOR BANDWIDTH EXTENSION - An apparatus and method for deciding an adaptive noise level for bandwidth extension are provided. The apparatus includes a noise level decider for deciding a high-band noise level for bandwidth extension according to tonality of an input signal, a pitch frequency analyzer for detecting a pitch frequency of the input signal and analyzing correlation between the detected pitch frequency and a frequency channel, and a noise level controller for adaptively controlling the decided high-band noise level based on the analyzed correlation of the pitch frequency and the frequency channel. | 04-15-2010 |

20100284459 | APPARATUS FOR ENCODING AND DECODING IMAGE USING ADAPTIVE DCT COEFFICIENT SCANNING BASED ON PIXEL SIMILARITY AND METHOD THEREFOR - The present invention discloses an encoding apparatus using a Discrete Cosine Transform (DCT) scanning, which includes: a mode selection means for selecting an optimal mode for intra prediction; an intra prediction means for performing intra prediction onto video inputted based on the mode selected in the mode selection means; a DCT and quantization means for performing DCT and quantization onto residual coefficients of a block outputted from the intra prediction means; and an entropy encoding means for performing entropy encoding onto DCT coefficients acquired from the DCT and quantization by using a scanning mode decided based on pixel similarity of the residual coefficients. | 11-11-2010 |

20110188581 | FILTER AND FILTERING METHOD FOR DEBLOCKING OF INTRA MACROBLOCK - Provided is a method and apparatus for adaptively performing deblocking filtering using a quantization parameter, based on a video block unit in a boundary between macroblocks including an intra macroblock. The filter and filtering method may enhance a compression rate of a high resolution video and enhance a video compression environment. | 08-04-2011 |

20110200243 | MAGNETIC RESONANCE IMAGING APPARATUS AND METHOD - Disclosed is a magnetic resonance imaging apparatus comprising static magnetic field generation means, gradient magnetic field generation means, high-frequency magnetic field generation means, reception means, signal processing means, and control means which controls the gradient magnetic field generation means, the high-frequency magnetic field generation means, the reception means, and the signal processing means, wherein said apparatus comprises: approximation means that approximates the output error of the gradient magnetic field using a combination of multiple parameter values with respect to each direction of the gradient magnetic field; evaluation means that evaluates the combinations of multiple parameter values based on the image quality of a magnetic resonance image that is reconstructed while taking into account the output error of the gradient magnetic field that has been approximated by the approximation means; and determination means that, based on the result of the evaluation by the evaluation means, determines a desired combination among the combinations of multiple parameter values. | 08-18-2011 |

20120020579 | IMAGE ENCODER AND DECODER USING UNIDIRECTIONAL PREDICTION - The present invention relates to an image encoding and decoding technique, and more particularly, to an image encoder and decoder using unidirectional prediction. The image encoder includes a dividing unit to divide a macro block into a plurality of sub-blocks, a unidirectional application determining unit to determine whether an identical prediction mode is applied to each of the plurality of sub-blocks, and a prediction mode determining unit to determine a prediction mode with respect to each of the plurality of sub-blocks based on a determined result of the unidirectional application determining unit. | 01-26-2012 |

20130272395 | IMAGE ENCODER AND DECODER USING UNDIRECTIONAL PREDICTION - The present invention relates to an image encoding and decoding technique, and more particularly, to an image encoder and decoder using unidirectional prediction. The image encoder includes a dividing unit to divide a macro block into a plurality of sub-blocks, a unidirectional application determining unit to determine whether an identical prediction mode is applied to each of the plurality of sub-blocks, and a prediction mode determining unit to determine a prediction mode with respect to each of the plurality of sub-blocks based on a determined result of the unidirectional application determining unit. | 10-17-2013 |

20130343452 | APPARATUS FOR ENCODING AND DECODING IMAGE USING ADAPTIVE DCT COEFFICIENT SCANNING BASED ON PIXEL SIMILARITY AND METHOD THEREFOR - The present invention discloses an encoding apparatus using a Discrete Cosine Transform (DCT) scanning, which includes a mode selection means for selecting an optimal mode for intra prediction; an intra prediction means for performing intra prediction onto video inputted based on the mode selected in the mode selection means; a DCT and quantization means for performing DCT and quantization onto residual coefficients of a block outputted from the intra prediction means; and an entropy encoding means for performing entropy encoding onto DCT coefficients acquired from the DCT and quantization by using a scanning mode decided based on pixel similarity of the residual coefficients. | 12-26-2013 |

20140037000 | APPARATUS FOR ENCODING AND DECODING IMAGE USING ADAPTIVE DCT COEFFICIENT SCANNING BASED ON PIXEL SIMILARITY AND METHOD THEREFOR - The present invention discloses an encoding apparatus using a Discrete Cosine Transform (DCT) scanning, which includes a mode selection means for selecting an optimal mode for intra prediction; an intra prediction means for performing intra prediction onto video inputted based on the mode selected in the mode selection means; a DCT and quantization means for performing DCT and quantization onto residual coefficients of a block outputted from the intra prediction means; and an entropy encoding means for performing entropy encoding onto DCT coefficients acquired from the DCT and quantization by using a scanning mode decided based on pixel similarity of the residual coefficients. | 02-06-2014 |

20140362913 | IMAGE ENCODER AND DECODER USING UNDIRECTIONAL PREDICTION - The present invention relates to an image encoding and decoding technique, and more particularly, to an image encoder and decoder using unidirectional prediction. The image encoder includes a dividing unit to divide a macro block into a plurality of sub-blocks, a unidirectional application determining unit to determine whether an identical prediction mode is applied to each of the plurality of sub-blocks, and a prediction mode determining unit to determine a prediction mode with respect to each of the plurality of sub-blocks based on a determined result of the unidirectional application determining unit. | 12-11-2014 |

20140362914 | IMAGE ENCODER AND DECODER USING UNDIRECTIONAL PREDICTION - The present invention relates to an image encoding and decoding technique, and more particularly, to an image encoder and decoder using unidirectional prediction. The image encoder includes a dividing unit to divide a macro block into a plurality of sub-blocks, a unidirectional application determining unit to determine whether an identical prediction mode is applied to each of the plurality of sub-blocks, and a prediction mode determining unit to determine a prediction mode with respect to each of the plurality of sub-blocks based on a determined result of the unidirectional application determining unit. | 12-11-2014 |

20140362915 | 12-11-2014 | |

20140362916 | 12-11-2014 |