Abstract: To improve image quality, a rate control encoding method using skip mode information is disclosed. The method includes calculating a skip mode occurrence frequency with respect to frames inside a window previous to a current window and comparing the calculated skip mode occurrence frequency with a reference value. In the case that the calculated skip mode occurrence frequency exceeds the reference value, an allocation number of bits with respect to an intra frame inside the current window is allocated to be more than an initial target number of bits and frames inside the current window are encoded. In the case that the calculated skip mode occurrence frequency does not exceed reference value, the allocation number of bits is allocated to be equal to the initial target number of bits and the frames inside the current window are encoded.

Abstract: An intra prediction encoding apparatus includes: an optimal filter selecting unit for providing a plurality of extrapolation prediction filter candidates for filtering pixels adjacent to a current block to be encoded, with respect to each intra prediction direction or prediction mode of the current block, and selecting a filter having lowest encoding cost among the plurality of extrapolation prediction filter candidates; a residual signal generating unit for generating an extrapolation prediction value of the current block through the filter selected by the optimal filter selecting unit, and generating a residual signal by calculating a difference between a generated extrapolation prediction value of the current block and a pixel value of the current block; a transform and quantization unit for performing transform and quantization on the residual signal generated by the residual signal generating unit; and an entropy encoding unit for performing entropy encoding on a transformed and quantized residual signal

Abstract: The present disclosure relates to an apparatus and method for determining an adaptive filter tap to encode a wavelet transform coefficient, a wavelet transform apparatus and a method using the same, and a recording medium for the same, wherein the filter tap is determined rendering the high-band energy to be minimized, based not only on whether an edge is present but also on the edge location so as to adaptively determine the filter tap for an efficient coding of the wavelet transform coefficient. Therefore, the disclosure is able to prevent ringing artifacts and increase coding efficiency while maintaining clear definition on the edges.

Abstract: An intra prediction encoding apparatus includes: an optimal filter selecting unit for providing a plurality of extrapolation prediction filter candidates for filtering pixels adjacent to a current block to be encoded, with respect to each intra prediction direction or prediction mode of the current block, and selecting a filter having lowest encoding cost among the plurality of extrapolation prediction filter candidates; a residual signal generating unit for generating an extrapolation prediction value of the current block through the filter selected by the optimal filter selecting unit, and generating a residual signal by calculating a difference between a generated extrapolation prediction value of the current block and a pixel value of the current block; a transform and quantization unit for performing transform and quantization on the residual signal generated by the residual signal generating unit; and an entropy encoding unit for performing entropy encoding on a transformed and quantized residual signal

Abstract: A method and apparatus for encoding/decoding an image by using an extended skip mode are provided. The method includes setting a backward reference block motion vector with respect to an adjacent block of a current block as a predictive motion vector of the current block or determining a predictive motion vector from a forward reference block motion vector with respect to a block located in a backward reference picture at the same position as the current block, performing motion compensation by using the predictive motion vector, and setting a prediction mode when the motion compensation results in satisfaction of an optimal skip condition.

Abstract: A video encoding/decoding apparatus and method using adaptive encoding/decoding mode indexing are provided. A video encoding apparatus includes: a probability generation unit for calculating a probability of each encoding mode of blocks completely encoded before a current block; a bit assignment unit for assigning and indexing a bin string according to the probability of each encoding mode, which is calculated by the probability generation unit; and a video encoding unit for encoding an encoding mode of the current block, based on the bin string assigned by the bit assignment unit, when the current block is encoded.

Abstract: An encoding method and encoding apparatus for B-transform, and encoded data for same are provided. The apparatus is for encoding input data and includes: a B-transform unit for performing a B-transform on the input data to generate a binary expression; and an encoder for removing one or more binary symbols from the binary expression and scanning the binary expression with the one or more binary symbols removed to generate a bitstream. According to the method and apparatus, it is possible to encode uniform distribution data efficiently, and using the B-transform by its characteristics for reducing the bit number in the generation of the binary expressions from the B-transform operation on the uniform distribution data enhances the data compression performance.

Abstract: The present disclosure relates to an encoding method and to an encoding apparatus for B-transform, and to encoded data for same. The apparatus is for encoding input data and includes: a B-transform unit for performing a B-transform on the input data to generate a binary expression; and an encoder for removing one or more binary symbols from the binary expression and scanning the binary expression with the one or more binary symbols removed to generate a bitstream. According to the present disclosure, it is possible to encode uniform distribution data efficiently, and using the B-transform by its characteristics for reducing the bit number in the generation of the binary expressions from the B-transform operation on the uniform distribution data enhances the data compression performance.

Abstract: The present disclosure relates to an apparatus and method for determining an adaptive filter tap to encode a wavelet transform coefficient, a wavelet transform apparatus and a method using the same, and a recording medium for the same, wherein the filter tap is determined rendering the high-band energy to be minimized, based not only on whether an edge is present but also on the edge location so as to adaptively determine the filter tap for an efficient coding of the wavelet transform coefficient. Therefore, the disclosure is able to prevent ringing artifacts and increase coding efficiency while maintaining clear definition on the edges.