Joint chroma residual video coding

A method of encoding video data, the method comprising:

• determining first residual samples for a first chroma component of a block of the video data, wherein the first residual samples correspond to a difference between a first chroma block of the first chroma component and a first prediction block of the first chroma component;
• determining intermediate reconstructed samples based on the first residual samples and a second prediction block of the second chroma component;
• determining second residual samples for the second chroma component of the block of video data, wherein the second residual samples correspond to a difference between a second chroma block of the second chroma component and the intermediate reconstructed samples;
• and
• outputting, in a bitstream of encoded video data, syntax elements representing the first residual samples and the second residual samples.

A device for decoding video data, the device comprising:

• a memory configured to store the video data;
• one or more processors implemented in circuitry and configured to:
• receive information for first residual samples for a first chroma component of a block of the video data, wherein the first residual samples correspond to a difference between a first chroma block of the first chroma component and a first prediction block of the first chroma component;
• determine intermediate reconstructed samples based on the first residual samples;
• receive information for second residual samples for a second chroma component of the block of video data, wherein the second residual samples correspond to a difference between a second chroma block of the second chroma component and the intermediate reconstructed samples;
• reconstruct the first chroma block based on the first residual samples and the first prediction block;
• reconstruct the second chroma block based on the second residual samples and the intermediate reconstructed samples;
• and
• output decoded video data comprising the reconstructed first chroma block and the reconstructed second chroma block.

A device of encoding video data, the device comprising:

• a memory configured to store video data;
• one or more processors implemented in circuitry and configured to:
• determine first residual samples for a first chroma component of a block of the video data, wherein the first residual samples correspond to a difference between a first chroma block of the first chroma component and a first prediction block of the first chroma component;
• determine intermediate reconstructed samples based on the first residual samples and a second prediction block of the second chroma component;
• determine second residual samples for the second chroma component of the block of video data, wherein the second residual samples correspond to a difference between a second chroma block of the second chroma component and the intermediate reconstructed samples;
• and
• output, in a bitstream of encoded video data, syntax elements representing the first residual samples and the second residual samples.