An image coding apparatus, including an encoder and a memory, and an image coding method are provided. In the image coding apparatus, the encoder executes operations, including obtaining a reference-specific image from storage accessible by the encoder, the reference-specific image being referenced from one or more other images to be displayed, and storing the reference-specific image in the memory. The operations further include encoding one or more to-be-displayed images by referring to the reference-specific image, wherein the obtained reference-specific image is formed by integrating a plurality of images. An image decoding apparatus and an image decoding method are also provided.

Provided is an inter-layer video decoding method including obtaining a disparity vector of a current block included in a first layer image; determining a block of a second layer image corresponding to the current block by using the obtained disparity vector; determining a reference block including a sample that contacts a boundary of the block; obtaining a motion vector of the reference block; and determining a motion vector of the current block included in the first layer image by using the obtained motion vector.

Provided are an encoding device using predictive coding in a screen and a method thereof, and a decoding device and a method thereof. The encoding device is capable of generating a prediction block of a current block according to one of methods for generating a plurality of predetermined prediction blocks, and outputting at least one of encoding information and differential blocks as bitstream by entropy encoding according to whether differential blocks are encoded or not.

Provided are an encoding device using predictive coding in a screen and a method thereof, and a decoding device and a method thereof. The encoding device is capable of generating a prediction block of a current block according to one of methods for generating a plurality of predetermined prediction blocks, and outputting at least one of encoding information and differential blocks as bitstream by entropy encoding according to whether differential blocks are encoded or not.

Techniques are provided to encode and decode image data comprising a tone mapped (TM) image with HDR reconstruction data in the form of luminance ratios and color residual values. In an example embodiment, luminance ratio values and residual values in color channels of a color space are generated on an individual pixel basis based on a high dynamic range (HDR) image and a derivative tone-mapped (TM) image that comprises one or more color alterations that would not be recoverable from the TM image with a luminance ratio image. The TM image with HDR reconstruction data derived from the luminance ratio values and the color-channel residual values may be outputted in an image file to a downstream device, for example, for decoding, rendering, and/or storing. The image file may be decoded to generate a restored HDR image free of the color alterations.

A video encoder, a video decoder, and a corresponding method are provided. The method includes: parsing a bitstream to obtain an index, where the index indicates a target candidate motion vector group of a current coding block; determining the target candidate motion vector group in an affine candidate motion vector list based on the index, where the affine candidate motion vector list includes at least a first candidate motion vector group, the first candidate motion vector group is obtained based on a first group of control points of a first neighboring affine coding block, and the first group of control points is determined based on a CTU located relative to the current coding block, wherein the first neighboring affine coding block is located in the CTU; and predicting a predicted sample value of the current coding block based on the target candidate motion vector group.

A video encoder, a video decoder, and a corresponding method are provided. The method includes: parsing a bitstream to obtain an index, where the index indicates a target candidate motion vector group of a current coding block; determining the target candidate motion vector group in an affine candidate motion vector list based on the index, where the affine candidate motion vector list includes at least a first candidate motion vector group, the first candidate motion vector group is obtained based on a first group of control points of a first neighboring affine coding block, and the first group of control points is determined based on a CTU located relative to the current coding block, wherein the first neighboring affine coding block is located in the CTU; and predicting a predicted sample value of the current coding block based on the target candidate motion vector group.

A first predictor is applied to an input image to generate first-stage predicted codewords approximating prediction target codewords of a prediction target image. Second-stage prediction target values are created by performing an inverse cascade operation on the prediction target codewords and the first-stage predicted codewords. A second predictor is applied to the input image to generate second-stage predicted values approximating the second-stage prediction target values. Multiple sets of cascade prediction coefficients are generated to comprise first and second sets of cascade prediction coefficients specifying the first and second predictors. The multiple sets of cascade prediction coefficients are encoded, in a video signal, as image metadata. The video signal is further encoded with the input image.

A first predictor is applied to an input image to generate first-stage predicted codewords approximating prediction target codewords of a prediction target image. Second-stage prediction target values are created by performing an inverse cascade operation on the prediction target codewords and the first-stage predicted codewords. A second predictor is applied to the input image to generate second-stage predicted values approximating the second-stage prediction target values. Multiple sets of cascade prediction coefficients are generated to comprise first and second sets of cascade prediction coefficients specifying the first and second predictors. The multiple sets of cascade prediction coefficients are encoded, in a video signal, as image metadata. The video signal is further encoded with the input image.

A three-dimensional data encoding method includes: calculating a prediction residual that is a difference between information of a three-dimensional point included in point cloud data and a predicted value; and generates a bitstream including first information with respect to the prediction residual, second information indicating a bit count of the first information, and third information indicating a bit count of the second information.