The present disclosure relates to signaling of sample adaptive offset (SAO) parameters determined to minimize an error between an original image and a reconstructed image in video encoding and decoding operations. An SAO decoding method includes obtaining context-encoded leftward SAO merge information and context-encoded upward SAO merge information from a bitstream of a largest coding unit (MCU); obtaining SAO on/off information context-encoded with respect to each color component, from the bitstream; if the SAO on/off information indicates to perform SAO operation, obtaining absolute offset value information for each SAO category bypass-encoded with respect to each color component, from the bitstream; and obtaining one of band position information and edge class information bypass-encoded with respect to each color component, from the bitstream.

The present disclosure relates to signaling of sample adaptive offset (SAO) parameters determined to minimize an error between an original image and a reconstructed image in video encoding and decoding operations. An SAO decoding method includes obtaining context-encoded leftward SAO merge information and context-encoded upward SAO merge information from a bitstream of a largest coding unit (MCU); obtaining SAO on/off information context-encoded with respect to each color component, from the bitstream; if the SAO on/off information indicates to perform SAO operation, obtaining absolute offset value information for each SAO category bypass-encoded with respect to each color component, from the bitstream; and obtaining one of band position information and edge class information bypass-encoded with respect to each color component, from the bitstream.

A compression device for compressing image data generated by a computed tomography (CT) imaging system is described herein. The compression device is configured to compress the image data by implementing a method including receiving image data from the CT imaging system and requantizing the image data in a square root domain. The method further includes identifying a group of projections (GOP) in the image data, including a first projection and a plurality of subsequent projections, and performing spatial-delta encoding on the first projection and temporal-delta encoding on each of the plurality of subsequent projections. The method also includes identifying a signed value in the GOP, and converting the signed value to an unsigned value. The method further includes entropy coding the image data in the GOP, and packetizing the GOP for transmission or storage.

A video encoding method includes deriving entry point information specifying an entry point of a substream for a picture. The entry point information may include a number syntax element representing a number of offset syntax elements in a slice header; an offset syntax element representing an entry point offset between in bytes two entry points; and a length syntax element representing a bits length of the offset syntax element. A value of the length syntax element plus one corresponds to the bits length of the offset syntax element and the length syntax element is signaled when the number of the offset syntax elements is larger than 0. A value of the number syntax element corresponds to the number of offset syntax elements in the slice header, and the offset syntax element is signaled when the number of the offset syntax elements is larger than 0.

A video encoding method includes deriving entry point information specifying an entry point of a substream for a picture. The entry point information may include a number syntax element representing a number of offset syntax elements in a slice header; an offset syntax element representing an entry point offset between in bytes two entry points; and a length syntax element representing a bits length of the offset syntax element. A value of the length syntax element plus one corresponds to the bits length of the offset syntax element and the length syntax element is signaled when the number of the offset syntax elements is larger than 0. A value of the number syntax element corresponds to the number of offset syntax elements in the slice header, and the offset syntax element is signaled when the number of the offset syntax elements is larger than 0.

The present disclosure relates to a method and apparatus for improving the encoding efficiency by adaptively changing the resolution of the motion vector in the inter prediction encoding and inter prediction decoding of a video. The apparatus includes: a predicted motion vector calculator for calculating a predicted motion vector of a current block to be encoded using motion vectors of one or more surrounding blocks; and a skip mode encoder for encoding a result of performing a prediction of the current block and information indicating that the current block is a skip block when the predicted motion vector satisfies a skip condition, wherein at least one motion vector among the motion vectors of the surrounding blocks and the motion vector of the current block has a resolution different from resolutions of the other motion vectors.

The present disclosure relates to a method and apparatus for improving the encoding efficiency by adaptively changing the resolution of the motion vector in the inter prediction encoding and inter prediction decoding of a video. The apparatus includes: a predicted motion vector calculator for calculating a predicted motion vector of a current block to be encoded using motion vectors of one or more surrounding blocks; and a skip mode encoder for encoding a result of performing a prediction of the current block and information indicating that the current block is a skip block when the predicted motion vector satisfies a skip condition, wherein at least one motion vector among the motion vectors of the surrounding blocks and the motion vector of the current block has a resolution different from resolutions of the other motion vectors.

An image coding device is provided with a determination unit which determines whether to apply an orthogonal transform to a transform block obtained by dividing a prediction difference signal indicating a difference between an input image and a predicted image or perform a transform skip by which the orthogonal transform is not applied, and an orthogonal transform unit which performs processing selected on the basis of the determination, the image coding device comprising a quantization unit which, when the transform skip is selected on the basis of the determination, quantizes the transform block using a first quantization matrix in which the quantization roughnesses of all elements previously shared with a decoding side are equal, and when the orthogonal transform is applied to the transform block on the basis of the determination, quantizes the transform block using the first quantization matrix or a second quantization matrix that is transmitted to the decoding side.

An image coding device is provided with a determination unit which determines whether to apply an orthogonal transform to a transform block obtained by dividing a prediction difference signal indicating a difference between an input image and a predicted image or perform a transform skip by which the orthogonal transform is not applied, and an orthogonal transform unit which performs processing selected on the basis of the determination, the image coding device comprising a quantization unit which, when the transform skip is selected on the basis of the determination, quantizes the transform block using a first quantization matrix in which the quantization roughnesses of all elements previously shared with a decoding side are equal, and when the orthogonal transform is applied to the transform block on the basis of the determination, quantizes the transform block using the first quantization matrix or a second quantization matrix that is transmitted to the decoding side.

Systems and methods for improving determination of encoded image data using a video encoding pipeline, which includes a first transcode engine that entropy encodes a first portion of a bin stream to determine a first bit stream including first encoded image data that indicates a first coding group row and that determines first characteristic data corresponding to the first bit stream to facilitate communicating a combined bit stream; and a second transcode engine that entropy encodes a second portion of the bin stream to determine a second bit stream including second encoded image data that indicates a second coding group row while the first transcode engine entropy encodes the first portion of the bin stream and that determines second characteristic data corresponding to the second bit stream to facilitate communicating the combined bit stream, which includes the first bit stream and the second bit stream, to a decoding device.