Method and apparatus for video coding with adaptive clipping

A method for encoding a picture, comprising:

• accessing an original block to be encoded, a prediction block and a residual block corresponding to the original block;
• determining that a first element in the original block or the prediction block is close to an upper bound for clipping;
• replacing a first element in the residual block corresponding to the first element in the original block or the prediction block with a first value that is greater than the first element in the residual block;
• encoding and decoding the residual block with the replaced element to form a decoded residual block;
• forming a reconstructed block based on the prediction block and the decoded residual block;
• and
• replacing a first element in the reconstructed block corresponding to the first element in the residual block with the upper bound for clipping if the first element in reconstructed block exceeds the upper bound for clipping.

An apparatus for encoding a picture, comprising:

• at least one memory and one or more processors coupled to the at least one memory, the one or more processors being configured to:
• access an original block to be encoded, a prediction block and a residual block corresponding to the original block;
• determine that a first element in the original block or the prediction block is close to an upper bound for clipping;
• replace a first element in the residual block corresponding to the first element in the original block or the prediction block with a first value that is greater than the first element in the residual block;
• encode and decode the residual block with the replaced element to form a decoded residual block;
• form a reconstructed block based on the prediction block and the decoded residual block;
• and
• replace a first element in the reconstructed block corresponding to the first element in the residual block with the upper bound for clipping if the first element in reconstructed block exceeds the upper bound for clipping.

A computer readable medium having stored thereon computer executable instructions that, when executed, implement a method for encoding a picture, the method comprising:

• accessing an original block to be encoded, a prediction block and a residual block corresponding to the original block;
• determining that a first element in the original block or the prediction block is close to an upper bound for clipping;
• replacing a first element in the residual block corresponding to the first element in the original block or the prediction block with a first value that is greater than the first element in the residual block;
• encoding and decoding the residual block with the replaced element to form a decoded residual block;
• forming a reconstructed block based on the prediction block and the decoded residual block;
• and
• replacing a first element in the reconstructed block corresponding to the first element in the residual block with the upper bound for clipping if the first element in reconstructed block exceeds the upper bound for clipping.