Nec Corporation

Junji Tajime

Keiichi Chono

Yuzo Senda

Hirofumi Aoki

Kenta Senzaki

Tetsuro Takizawa

A video decoding device and method, including extracting PCM block size information including a threshold, from a bitstream, determining the threshold based on the extracted PCM block size information; parsing a PCM header from the bitstream with respect to an encoded block, only when said encoded block is prediction mode of intra prediction and a block size of said encoded block is equal to or greater than the determined threshold, controlling an entropy decoding process and a PCM decoding process based on the parsed PCM header; parsing transformed data of a prediction error data of an image in the bitstream; and PCM-decoding PCM data of the image in the bitstream, wherein the decoding performs the decoding operation based on the prediction mode being intra prediction and based on the block size of the encoded block being equal to or greater than the determined threshold.

Video encoding device, video decoding device, video encoding method, video decoding method, and program

A video encoding device includes: transform meansfor transforming an image block; entropy encoding meansfor entropy-encoding transformed data of the image block transformed by the transform means; PCM encoding meansfor PCM-encoding the image block; multiplex data selection meansfor selecting output data of the entropy encoding meansor the PCM encoding means, in a block of a block size set from the outside; and multiplexing meansfor embedding a PCM header in a bitstream, in the block of the set from the outside block size.

A video encoding device includes: pixel bit length increasing means for increasing a pixel bit length of an input image based on pixel bit length increase information; transform means for transforming output data of the pixel bit length increasing means; entropy encoding means for entropy-encoding output data of the transform means; non-compression encoding means for non-compression-encoding input data; multiplexed data selection means for selecting output data of the entropy encoding means or output data of the non-compression encoding means; and multiplexing means for multiplexing the pixel bit length increase information in a bitstream, wherein a pixel bit length of an image corresponding to the output data of the entropy encoding means and a pixel bit length of an image corresponding to the output data of the non-compression encoding means are different from each other.

Video encoding device, video decoding device, video decoding method, video decoding method, and program

When injecting pseudo random noise to an area centered on a block boundary, a video encoding device and a video decoding device prevent injection of pseudo random noise to an area including a reference image for subsequent planar mode filtering, in order to suppress linear artifacts. The video encoding device includes: an inverse quantization unit for inverse-quantizing a quantization index to obtain a quantization representative value; an inverse frequency transform unit for inverse-transforming the quantization representative value obtained by the inverse quantization unit, to obtain a reconstructed image block; and an adaptive distortion removal filter unit for injecting pseudo random noise to an area centered on a boundary of the reconstructed image block, wherein the adaptive distortion removal filter unit does not inject pseudo random noise to an area including a reference image for planar mode filtering.

Video image encoding and decoding device using adaptive pseudo random noise injection during planar mode filtering

In the present invention, reconstructed images for prediction are stored in uncompressed reference picture memory and compressed reference picture memory. A video decoder stores in uncompressed reference picture memory a reconstructed image of a frame to be decoded which has been generated on the basis of a prediction, and among reconstructed images which have been stored in the uncompressed reference picture memory, compresses a reconstructed image that will not be used for prediction of the frame to be decoded and stores the image in the compressed reference picture memory. Using the reconstructed images which are stored in the uncompressed reference picture memory and the compressed reference picture memory, the video bitstream is decoded into a video.

Video decoding apparatus, video coding apparatus, video decoding method, video coding method, and program

A memory compression and expansion section (of FIG.) applies compression to a decoded image, and the result is stored in a frame memory. Based on an occupied content of the frame memory (FIG.), in case that the number of coded bits for a single or a plurality of memory compression processing blocks or for every control unit of memory compression processing exceeds the number of bits of a memory access unit or is lacking, a memory access width control section (of FIG.) applies control to a quantizer control section (of FIG.) so that the number of coded bits is conformed to be equal to or less than the number of bits of memory access unit.

Moving picture decoding apparatus and moving picture decoding method

To reduce a processing delay when re-encoding compressed moving pictures, and provide a compressed moving picture re-encoding apparatus with higher picture quality. Complexity measure computing unit computes respective complexity measures in two or more kinds of prescribed predetermined periods or numbers of pictures, using either or both of a quantizer step size and a number of bits of an input compressed moving picture stream. Also, picture group quantizer step size computing unit outputs a particular complexity measure from a plurality of complexity measures, and quantizer step size adjusting unit computes the quantizer step size using a pre-set average bit rate and the output complexity measure. Moreover, a quantizer step size selector that adjusts the quantizer step size every particular period according to a difference (excess or deficiency) between a target number of bits and an actual number of bits, computes the quantizer step size that is used in re-encoding, and performs rate control by taking the quantizer step size and the quantizer step size in the input compressed moving picture stream as input, and outputting the quantizer step size that is used in actual re-encoding. In this way, re-encoding is performed with a variable bit rate, and a compressed moving picture stream whose bit rate has been changed is output.

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Tokyo, Japan

Junji Tajime