Image coding/decoding method and apparatus using correlation in ycbcr

A video decoding apparatus for predictively decoding a target block, comprising a predictor configured to:

• receive a bitstream and generate a residual block for a chroma block;
• generate reconstructed information in a luma block corresponding to the chroma block and reconstructed neighboring information about the luma block;
• generate reconstructed neighboring information about the chroma block;
• determine a scaling value and an offset value based on the reconstructed neighboring information about the chroma block and the reconstructed neighboring information about the luma block;
• generate a prediction block for the chroma block by applying the determined scaling value and offset value to the reconstructed information in the luma block;
• and
• generate a reconstructed block for the chroma block based on the residual block for the chroma block and the prediction block for the chroma block.

A video decoding method for predictively decoding a target block, comprising:

• receiving a bitstream and generating a residual block for a Cr block;
• generating reconstructed information in a Cb block corresponding to the Cr block and reconstructed neighboring information about the Cb block;
• generating reconstructed neighboring information about the Cr block;
• determining a scaling value and an offset value based on the reconstructed neighboring information about the Cr block and the reconstructed neighboring information about the Cb block;
• generating a prediction block for the Cr block by applying the determined scaling value and offset value to the reconstructed information in the Cb block;
• and
• generating a reconstructed block for the Cr block based on the residual block for the Cr block and the prediction block for the Cr block.

A video decoding apparatus for predictively decoding a target block, comprising a predictor configured to:

• receive a bitstream and generate a residual block for a Cr block;
• generate reconstructed information in a Cb block corresponding to the Cr block and reconstructed neighboring information about the Cb block;
• generate reconstructed neighboring information about the Cr block;
• determine a scaling value and an offset value based on the reconstructed neighboring information about the Cr block and the reconstructed neighboring information about the Cb block;
• generate a prediction block for the Cr block by applying the determined scaling value and offset value to the reconstructed information in the Cb block;
• and
• generate a reconstructed block for the Cr block based on the residual block for the Cr block and the prediction block for the Cr block.