Abstract: An image coding method and apparatus considering human visual characteristics are provided. The image coding method comprises (a) modeling image quality distribution of an input image in units of scenes such that the quality of an image input in units of scenes is gradually lowered from a region of interest to a background region, (b) determining a quantization parameter of each region constituting one scene according to the result of modeling of image quality distribution, (c) quantizing image data in accordance with the quantization parameter, and (d) coding entropy of the quantized image data.

Abstract: An image coding method and apparatus considering human visual characteristics are provided. The image coding method comprises (a) modeling image quality distribution of an input image in units of scenes such that the quality of an image input in units of scenes is gradually lowered from a region of interest to a background region, (b) determining a quantization parameter of each region constituting one scene according to the result of modeling of image quality distribution, (c) quantizing image data in accordance with the quantization parameter, and (d) coding entropy of the quantized image data.

Abstract: An image encoding and decoding apparatus and method, the image encoding and decoding apparatus includes: an encoding unit adjusting at least one weight value adaptively to the number of bits expressing each pixel of a current image, predicting a pixel value of a block of interest by performing an operation on a pixel value of at least one block having a pixel value similar to the pixel value of the block of interest among blocks included in a previous image and the at least one adjusted weight value, and encoding the pixel value of the block of interest using the predicted pixel value of the block of interest; and a decoding unit adjusting the at least one weight value adaptively to the number of bits, restoring the predicted pixel value of the block of interest by performing an operation on the pixel value of the at least one block having the pixel value similar to the pixel value of the block of interest among blocks included in the restored previous image and the at least one adjusted weight value, and dec

Abstract: In general, this disclosure describes techniques for coding video blocks using a color-space conversion process. A video coder, such as a video encoder or a video decoder, may determine whether to use color-space conversion for encoding the video data. In response to determining to use color-space conversion, the video coder may quantize data of a first color component of the video data using a first offset of a first quantization parameter (QP) and quantize data of a second color component of the video data using a second offset of a second QP, wherein the second color component is different than the first color component, and the second QP is different than the first QP. The video coder may further inverse quantize data of the first color component using the first offset and inverse quantize data of the second color component using the second offset.

Abstract: An image encoding and decoding apparatus and method, the image encoding and decoding apparatus includes: an encoding unit adjusting at least one weight value adaptively to the number of bits expressing each pixel of a current image, predicting a pixel value of a block of interest by performing an operation on a pixel value of at least one block having a pixel value similar to the pixel value of the block of interest among blocks included in a previous image and the at least one adjusted weight value, and encoding the pixel value of the block of interest using the predicted pixel value of the block of interest; and a decoding unit adjusting the at least one weight value adaptively to the number of bits, restoring the predicted pixel value of the block of interest by performing an operation on the pixel value of the at least one block having the pixel value similar to the pixel value of the block of interest among blocks included in the restored previous image and the at least one adjusted weight value, and dec

Abstract: An image encoding and decoding apparatus and method, the image encoding and decoding apparatus includes: an encoding unit adjusting at least one weight value adaptively to the number of bits expressing each pixel of a current image, predicting a pixel value of a block of interest by performing an operation on a pixel value of at least one block having a pixel value similar to the pixel value of the block of interest among blocks included in a previous image and the at least one adjusted weight value, and encoding the pixel value of the block of interest using the predicted pixel value of the block of interest; and a decoding unit adjusting the at least one weight value adaptively to the number of bits, restoring the predicted pixel value of the block of interest by performing an operation on the pixel value of the at least one block having the pixel value similar to the pixel value of the block of interest among blocks included in the restored previous image and the at least one adjusted weight value, and dec

Abstract: An image encoding and decoding apparatus and method, the image encoding and decoding apparatus includes: an encoding unit adjusting at least one weight value adaptively to the number of bits expressing each pixel of a current image, predicting a pixel value of a block of interest by performing an operation on a pixel value of at least one block having a pixel value similar to the pixel value of the block of interest among blocks included in a previous image and the at least one adjusted weight value, and encoding the pixel value of the block of interest using the predicted pixel value of the block of interest; and a decoding unit adjusting the at least one weight value adaptively to the number of bits, restoring the predicted pixel value of the block of interest by performing an operation on the pixel value of the at least one block having the pixel value similar to the pixel value of the block of interest among blocks included in the restored previous image and the at least one adjusted weight value, and dec

Abstract: A method, medium, and apparatus encoding and/or decoding an image in order to increase encoding and decoding efficiency by performing binary-arithmetic coding/decoding on a binary value of a syntax element using a probability model having the same syntax element probability value for respective context index information of each of at least two image components.

Abstract: A method, medium, and apparatus encoding and/or decoding an image in order to increase encoding and decoding efficiency by performing binary-arithmetic coding/decoding on a binary value of a syntax element using a probability model having the same syntax element probability value for respective context index information of each of at least two image components.

Abstract: A method, medium, and system encoding and/or decoding a moving picture. The moving picture encoding method may include selecting a prediction mode that is optimal for the macro blocks, which correspond to each other, of the color components of a current image based on the characteristics of a predetermined image, generating a predicted image for the current image according to the selected prediction mode, and encoding a moving picture using the predicted image. An optimal prediction mode can be adaptively applied to the macro blocks, which correspond to each other, of the color components, thereby increasing the moving picture's encoding and decoding efficiencies.

Abstract: A method, medium, and apparatus encoding and/or decoding an image in order to increase encoding and decoding efficiency by performing binary-arithmetic coding/decoding on a binary value of a syntax element using a probability model having the same syntax element probability value for respective context index information of each of at least two image components.

Abstract: A device for decoding video data includes a memory configured to store video data, and at least one processor. The at least one processor is configured to: determine a first bit-depth of luma residual samples for a block of video data, determine a second bit-depth of predicted chroma residual samples for the block of video data, adjust the luma residual samples based on the first bit-depth and the second bit-depth to produce bit-depth adjusted luma residual samples, determine chroma residual samples for the block of video data based on the bit-depth adjusted luma residual samples and the predicted chroma residual samples, and decode the block of video data based on the luma residual samples and the chroma residual samples.

Abstract: A device for decoding video data includes a memory configured to store video data, and at least one processor. The at least one processor may be configured to: determine luma residual samples for a block of video data, determine predictive chroma residual samples for the block of video data, scale the luma residual samples with a scale factor to produce scaled luma residual samples, and determine updated chroma residual samples based on the predictive chroma residual samples and the scaled luma residual samples.

Abstract: A coding method including dividing pixels of a chrominance component of an input image into blocks having a predetermined size; selecting one among a direct current prediction method, a vertical prediction method, a horizontal prediction method, and a hybrid prediction method according to a user's input; generating a prediction value of each pixel in a current block to be predictively coded, using at least one pixel value among pixel values in an upper reference block adjacent to the current block and in a side reference block adjacent to the current block, according to the selected prediction method; generating a differential value between the prediction value and a corresponding real pixel value in the current block; and coding the differential value and information on the selected prediction method using a predetermined coding method.

Abstract: A method, medium, and apparatus encoding and/or decoding an image in order to increase encoding and decoding efficiency by performing binary-arithmetic coding/decoding on a binary value of a syntax element using a probability model having the same syntax element probability value for respective context index information of each of at least two image components.

Abstract: A coding method including dividing pixels of a chrominance component of an input image into blocks having a predetermined size; selecting one among a direct current prediction method, a vertical prediction method, a horizontal prediction method, and a hybrid prediction method according to a user's input; generating a prediction value of each pixel in a current block to be predictively coded, using at least one pixel value among pixel values in an upper reference block adjacent to the current block and in a side reference block adjacent to the current block, according to the selected prediction method; generating a differential value between the prediction value and a corresponding real pixel value in the current block; and coding the differential value and information on the selected prediction method using a predetermined coding method.

Abstract: In palette-based coding, a video coder may form a so-called “palette” as a table of colors representing the video data of a given block. The video coder may code index values for one or more pixels values of a current block of video data, where the index values indicate entries in the palette that represent the pixel values of the current block. According to the techniques, a video coder determines one or more palette entries in a predictive palette that are copied to the current palette, and a number of new palette entries not in the predictive palette that are included in the current palette. The video coder calculates a size of the current palette equal to the sum of the number of the copied palette entries and the number of the new palette entries, and generates the current palette including the copied palette entries and the new palette entries.

Abstract: A method and apparatus for image coding using hierarchical sample adaptive band offset. The method includes decoding a signal of a portion of an image, determining a band offset type and offset of a portion of the image, utilizing the band offset type and offset to determine a sub-band, and reconstructing a pixel value according to the determined offset value.

Abstract: A method for sample adaptive offset (SAO) filtering in a video encoder is provided that includes estimating SAO parameters for color components of a largest coding unit (LCU) of a picture, wherein estimating SAO parameters includes using at least some non-deblock-filtered reconstructed pixels of the LCU to estimate the SAO parameters, performing SAO filtering on the reconstructed LCU according to the estimated SAO parameters, and entropy encoding SAO information for the LCU in a compressed video bit stream, wherein the SAO information signals the estimated SAO parameters for the LCU.

Abstract: A method, medium, and apparatus encoding and/or decoding an image in order to increase encoding and decoding efficiency by performing binary-arithmetic coding/decoding on a binary value of a syntax element using a probability model having the same syntax element probability value for respective context index information of each of at least two image components.