40results about How to "Efficient encoding/decoding" patented technology

Provided are a method and apparatus for effectively encoding / decoding remaining difference signals excluding sinusoidal components, from input audio signals. In the method and apparatus for encoding audio signals, sinusoidal analysis is performed on low frequency signals of less than a predetermined critical frequency in order to extract sinusoidal signals and then, an encoding operation is performed on the remaining difference signals excluding the sinusoidal signals, from input audio signals, by using linear prediction coding (LPC) analysis.

Provided are a block-based depth map coding method and apparatus and a 3D video coding method using the same. The depth map coding method decodes a received bitstream in units of blocks of a predetermined size using a bitplane decoding method to reconstruct a depth map. For example, the depth map coding method may decode the bitstream in units of blocks using the bitplane decoding method or an existing Discrete Cosine Transform (DCT)-based decoding method adaptively according to decoded coding mode information. The bitplane decoding method may include adaptively performing XOR operation in units of bitplane blocks. For example, a determination on whether or not to perform XOR operation may be done in units of bitplane blocks according to the decoded value of XOR operation information contained in the bitstream.

Video encoding / decoding method and apparatus using a block transformation are disclosed. The apparatus encodes the video through predicting each pixel in a current block of the video by using one or more adjacent pixels, which are encoded prior to encoding the current block and have the closest proximity to the pixels respectively in a predetermined prediction direction, and wherein the current block is sized L×M with L being unequal to M. It has become possible to predict the pixels in the block starting from closest one of the pixels in the prediction direction in order to provide more accurate block predictions and then raise the compression efficiency that leaps to more efficient video encoding / decoding performance.

An image decoding device is provided which includes an intra prediction module for reconstructing an intra prediction mode and creating a prediction block of a current block or a sub block, an inverse scanning module for converting residual signals into a quantization block, an inverse quantization module for inversely quantizing the quantization block, and an inverse transform module for inversely-transforming the inversely-quantized block. A quantization parameter predictor for deriving the quantization parameter is created using quantization parameters of a left coding unit and a top coding unit of a current coding unit. Therefore, it is possible to improve image quality by adaptively adjusting a quantization parameter of a current block depending on the size of a coding unit and enhance compression efficiency of an image by effectively encoding / decoding the quantization parameter to reduce the number of bits required for transmitting the quantization parameter.

Disclosed are an apparatus and a method for generating / recovering motion information based on predictive motion vector index encoding, and to an apparatus and a method for image encoding / decoding using the same. The image encoding / decoding apparatus according to an embodiment of the present invention comprises an image encoder which generates information on the index for a predictive motion vector of a current block based on the motion vector of identically located blocks of a reference frame and the motion vector of blocks existing near the current block, and generates motion information on the current block, including a differential motion vector obtained by subtracting the predictive motion vector from the motion vector of the current block, a reference frame index information and a predictive motion vector index information, when performing inter-prediction for the current block using the reference frame; and an image decoder which recovers the predictive motion vector based on the predictive motion vector index information, adds the recovered predictive motion vector and the differential motion vector to recover the motion vector of the objective block to be decoded, and recovers the objective block based on the recovered motion vector of the objective block.

According to the present invention, an adaptive scheme is applied to an image encoding apparatus that includes an inter-predictor, an intra-predictor, a transformer, a quantizer, an inverse quantizer, and an inverse transformer, wherein input images are classified into two or more different categories, and two or more modules from among the inter-predictor, the intra-predictor, the transformer, the quantizer, and the inverse quantizer are implemented to perform respective operations in different schemes according to the category to which an input image belongs. Thus, the invention has the advantage of efficiently encoding an image without the loss of important information as compared to a conventional image encoding apparatus which adopts a packaged scheme.

Video encoding / decoding method and apparatus using a block transformation are disclosed. The apparatus encodes the video through predicting each pixel in a current block of the video by using one or more adjacent pixels, which are encoded prior to encoding the current block and have the closest proximity to the pixels respectively in a predetermined prediction direction, and wherein the current block is sized L×M with L being unequal to M. It has become possible to predict the pixels in the block starting from closest one of the pixels in the prediction direction in order to provide more accurate block predictions and then raise the compression efficiency that leaps to more efficient video encoding / decoding performance.

A highly efficient encoding technique is realized even for a multiview video involved in local mismatches in illumination and color between cameras. A view synthesized picture corresponding to an encoding target frame is synthesized from an already encoded reference view frame taken at a reference view different from an encoding target view simultaneously with the encoding target frame at the encoding target view of a multiview video. For each processing unit region having a predetermined size, a reference region on an already encoded reference frame at the encoding target view corresponding to the view synthesized picture is searched for. A correction parameter for correcting a mismatch between cameras is estimated from the view synthesized picture for the processing unit region and the reference frame for the reference region. The view synthesized picture for the processing unit region is corrected using the estimated correction parameter. A video at the encoding target view is subjected to predictive encoding using the corrected view synthesized picture.

A reconstructed block creating method is provided which includes decoding an intra prediction mode using an intra prediction mode group indicator and a prediction mode index, constructing a prediction block, inversely quantizing a received residual signal using a quantization parameter and adaptively inversely transforming the residual signal using the intra prediction mode to create a residual block, and adding the prediction block and the residual block to create a reconstructed block. The quantization parameter is reconstructed using a minimum quantization CU size, and the minimum quantization CU size is determined by a parameter transmitted from a picture parameter set. Therefore, it is possible to improve image quality by adaptively adjusting a quantization parameter of a current block depending on the size of a coding unit and enhance compression efficiency of an image by effectively encoding / decoding the quantization parameter.

The present invention makes it possible to effectively encode / decode position information of leaves or nodes in tree-structured information by using a less amount of bits. The coding device according to the present invention includes a branching layer discriminating portion for identifying a hierarchical layer in which a leaf or node and a preceding leaf or node are separately branched and a position information coding portion for outputting a code corresponding to the identified hierarchical layer as a position information code for the leaf or node. Namely, merely information indicating a hierarchical layer in which a current leaf or node and a preceding leaf or node are separately branched is encoded as the position information of the leaf or node, thus increasing the efficiency of encoding leaf or node positions in the tree-structured information.

An image coding apparatus includes a block dividing unit configured to divide an input image into a plurality of blocks, a prediction unit configured to perform prediction based on coded pixels to generate prediction errors, a transformation unit configured to perform orthogonal transform to the prediction errors to generate transform coefficients, a quantization matrix generation unit configured to generate quantization matrices that are used to quantize the transform coefficients, a quantization matrix coding unit configured to calculate difference values by scanning the quantization matrices and to code the difference values, a quantization unit configured to generate quantization coefficients by quantizing the generated transform coefficients using the quantization matrices, and a coefficient coding unit configured to code the quantization coefficients, wherein the quantization matrix coding unit is configured to scan coefficients of the quantization matrices in a unidirectional manner to calculate the difference value.

According to the present invention, an adaptive scheme is applied to an image encoding apparatus that includes an inter-predictor, an intra-predictor, a transformer, a quantizer, an inverse quantizer, and an inverse transformer, wherein input images are classified into two or more different categories, and two or more modules from among the inter-predictor, the intra-predictor, the transformer, the quantizer, and the inverse quantizer are implemented to perform respective operations in different schemes according to the category to which an input image belongs. Thus, the invention has the advantage of efficiently encoding an image without the loss of important information as compared to a conventional image encoding apparatus which adopts a packaged scheme.

An image signal decoding method according to an embodiment of the present disclosure comprises the steps of: splitting a current picture into a plurality of tiles; decoding split information indicating a slice type, wherein the split information indicates whether a rectangular slice is to be applied; and when the split information indicates that the rectangular slice is to be applied, determining a slice on the basis of information indicating the size of a slice.

The invention relates to an image coding apparatus, an image coding method, an image decoding apparatus and an image decoding method. An image coding apparatus includes a block dividing unit configured to divide an input image into a plurality of blocks, a prediction unit configured to perform prediction based on coded pixels to generate prediction errors, a transformation unit configured to perform orthogonal transform to the prediction errors to generate transform coefficients, a quantization matrix generation unit configured to generate quantization matrices that are used to quantize the transform coefficients, a quantization matrix coding unit configured to calculate difference values by scanning the quantization matrices and to code the difference values, a quantization unit configured to generate quantization coefficients by quantizing the generated transform coefficients using the quantization matrices, and a coefficient coding unit configured to code the quantization coefficients, wherein the quantization matrix coding unit is configured to scan coefficients of the quantization matrices in a unidirectional manner to calculate the difference value.

The present invention relates to an image encoding method and an image decoding method, and the image decoding method according to one embodiment of the present invention may comprise the steps of: determining an initial motion vector of a current block by using a motion vector of a reconstructed area; searching for a motion vector of the current block on the basis of the initial motion vector; and generating a prediction sample of the current block by using the motion vector, wherein the initial motion vector includes a motion vector in a past direction and a motion vector in a future direction.

A reconstructed block creating method is provided which includes decoding an intra prediction mode using an intra prediction mode group indicator and a prediction mode index, constructing a prediction block, inversely quantizing a received residual signal using a quantization parameter and adaptively inversely transforming the residual signal using the intra prediction mode to create a residual block, and adding the prediction block and the residual block to create a reconstructed block. The quantization parameter is reconstructed using a minimum quantization CU size, and the minimum quantization CU size is determined by a parameter transmitted from a picture parameter set. Therefore, it is possible to improve image quality by adaptively adjusting a quantization parameter of a current block depending on the size of a coding unit and enhance compression efficiency of an image by effectively encoding / decoding the quantization parameter.

Provided are a block-based depth map coding method and apparatus and a 3D video coding method using the same. The depth map coding method decodes a received bitstream in units of blocks of a predetermined size using a bitplane decoding method to reconstruct a depth map. For example, the depth map coding method may decode the bitstream in units of blocks using the bitplane decoding method or an existing Discrete Cosine Transform (DCT)-based decoding method adaptively according to decoded coding mode information. The bitplane decoding method may include adaptively performing XOR operation in units of bitplane blocks. For example, a determination on whether or not to perform XOR operation may be done in units of bitplane blocks according to the decoded value of XOR operation information contained in the bitstream.

Disclosed are an apparatus and method for encoding / decoding additional intra-information. An apparatus for encoding / decoding additional intra-information according to one embodiment of the present invention comprises: an additional intra-information encoder, which selects an optimum segmentation combination and prediction mode for a coding unit in accordance with a variety of types of preset segmentation and prediction modes, looks up a table in accordance with the selected segmentation combination and prediction mode, and performs entropy-encoding based on the table; and an additional intra-information decoder, which looks up and parses the table based on an entropy-decoded signal, generates a segmentation and prediction mode string based on the result of the lookup and parsing, and performs intra-mode decoding on the basis of the generated segmentation and prediction mode string.

The invention relates to a coding apparatus, a coding method, a decoding apparatus, and a decoding method. An image coding apparatus includes a block dividing unit configured to divide an input image into a plurality of blocks, a prediction unit configured to perform prediction based on coded pixels to generate prediction errors, a transformation unit configured to perform orthogonal transform to the prediction errors to generate transform coefficients, a quantization matrix generation unit configured to generate quantization matrices that are used to quantize the transform coefficients, a quantization matrix coding unit configured to calculate difference values by scanning the quantization matrices and to code the difference values, a quantization unit configured to generate quantization coefficients by quantizing the generated transform coefficients using the quantization matrices, and a coefficient coding unit configured to code the quantization coefficients, wherein the quantization matrix coding unit is configured to scan coefficients of the quantization matrices in a unidirectional manner to calculate the difference value.

An image signal decoding method according to an embodiment of the present disclosure comprises the steps of: splitting a current picture into a plurality of tiles; decoding split information indicating a slice type, wherein the split information indicates whether a rectangular slice is to be applied; and when the split information indicates that the rectangular slice is to be applied, determining a slice on the basis of information indicating the size of a slice.

The present disclosure provides an apparatus for encoding additional intra-information includes an intra prediction mode selecting unit for performing an intra prediction by applying at least one of one or more predetermined types of partitions and one or more prediction modes with respect to a coding unit, and for selecting at least one of a partition among the one or more types of partitions and a prediction mode among the one or more prediction modes; a partitioning and prediction mode table lookup unit for looking up a table, and for generating a table hit signal if the table has at least one of a partition corresponding to the selected partition and a prediction mode corresponding to the selected prediction mode; and an entropy encoding unit for performing an encoding based on the table, if the table hit signal is received.

An image decoding method according to the present invention comprises the steps of: generating a merge candidate list of a current block; specifying any one of a plurality of merge candidates included in the merge candidate list; on the basis of a first affine seed vector and a second affine seed vector of the specified merge candidate, inducing a first affine seed vector and a second affine seed vector of the current block; using the first affine seed vector and the second affine seed vector of the current block, inducing an affine vector regarding a sub-block in the current block; and on the basis of the affine vector, performing motion compensation prediction regarding the sub-block.