An image processing apparatus, including processing circuitry configured to decode a bit stream to generate quantized data. The bit stream includes a flag, for each block, that specifies whether or not a difference quantization parameter is present in the bit stream. The flag is included in a first layer that is higher than a second layer in which the difference quantization parameter is set. The processing circuitry is configured to set, according to the flag, a current quantization parameter for a current sub block formed by block partitioning, which splits a block into smaller sub blocks. The processing circuitry is configured to inversely quantize the generated quantized data using the set current quantization parameter.

The present disclosure generally relates to a method and device of encoding a color picture having color components (Ec) comprising obtaining (11) a luminance component (L) and two chrominance components (C1, C2) from the color picture to be encoded. The method for encoding a color picture having color components comprising obtaining at least one chrominance component from the color picture to be encoded, the method further comprises: —determining a first factor based on the value of each pixel (i) of said luminance component; —obtaining at least one final chrominance component by scaling said at least one chrominance component by said first factor; and—encoding (13) said at least one final chrominance component.

The present disclosure generally relates to a method and device of encoding a color picture having color components (Ec) comprising obtaining (11) a luminance component (L) and two chrominance components (C1, C2) from the color picture to be encoded. The method for encoding a color picture having color components comprising obtaining at least one chrominance component from the color picture to be encoded, the method further comprises: —determining a first factor based on the value of each pixel (i) of said luminance component; —obtaining at least one final chrominance component by scaling said at least one chrominance component by said first factor; and—encoding (13) said at least one final chrominance component.

Downsampled video content is generated in a subsampling color space from linearized video content in the subsampling color space. The linearized video content represents a first spatial dimension, whereas the downsampled video content represents a second spatial dimension lower than the first spatial dimension. Opponent channel data is derived in a transmission color space from the downsampled video content. Output video content is generated from luminance data in the linearized video content and the opponent channel data in the transmission color space. The output video content may be decoded by a downstream recipient device to generate video content in an output color space.

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.

The present invention enables a receiving side to easily recognize a high-quality format corresponding to encoded image data included in an extended video stream. Two video streams including a basic video stream including encoded image data of basic format image data, and an extended video stream including encoded image data of high-quality format image data of one type selected from a plurality of types are generated. A container of a predetermined format including the basic video stream and the extended video stream is transmitted. Information indicating a high-quality format corresponding to the encoded image data included in the extended video stream is inserted into the extended video stream and/or the container.

The present invention enables a receiving side to easily recognize a high-quality format corresponding to encoded image data included in an extended video stream. Two video streams including a basic video stream including encoded image data of basic format image data, and an extended video stream including encoded image data of high-quality format image data of one type selected from a plurality of types are generated. A container of a predetermined format including the basic video stream and the extended video stream is transmitted. Information indicating a high-quality format corresponding to the encoded image data included in the extended video stream is inserted into the extended video stream and/or the container.

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.

Techniques are described for signaling information used to generate three-dimensional (3D) color lookup tables for color gamut scalability in multi-layer video coding. A lower layer of video data may include color data in a first color gamut and a higher layer of the video data may include color data in a second color gamut. To generate inter-layer reference pictures, a video encoder and/or video decoder performs color prediction to convert the color data of a reference picture in the first color gamut to the second color gamut. The video coder may perform color prediction using a 3D lookup table. According to the techniques, a video encoder may encode partition information and/or color values of a 3D lookup table generated for color gamut scalability. A video decoder may decode the partition information and/or color values to generate the 3D lookup table in order to perform color gamut scalability.

Techniques are described for signaling information used to generate three-dimensional (3D) color lookup tables for color gamut scalability in multi-layer video coding. A lower layer of video data may include color data in a first color gamut and a higher layer of the video data may include color data in a second color gamut. To generate inter-layer reference pictures, a video encoder and/or video decoder performs color prediction to convert the color data of a reference picture in the first color gamut to the second color gamut. The video coder may perform color prediction using a 3D lookup table. According to the techniques, a video encoder may encode partition information and/or color values of a 3D lookup table generated for color gamut scalability. A video decoder may decode the partition information and/or color values to generate the 3D lookup table in order to perform color gamut scalability.