Run-mode based coefficient coding for video coding

摘要

A video coding device is configured to code coefficients of residual blocks of video data. When a coefficient of a transform unit of video data has a scan order value that is less than a threshold and when the coefficient is the last significant coefficient in a scan order in the transform unit, the video coding device may execute a function to determine a mapping between data for the coefficient and a codeword index value, and code the data for the coefficient using a codeword associated with the codeword index value. The video coding device may comprise a video encoder or a video decoder, in some examples.

主权项

1. A method of coding video data, the method comprising, by a video coder:
when a first coefficient of a transform unit of video data has a first scan order value that is greater than or equal to a threshold or when the first coefficient is not the last significant coefficient in a scan order in the transform unit, the first scan order value representing a position of the first coefficient in the scan order:
determining a first codeword index value for the first coefficient from a codeword table; andcoding data for the first coefficient using a first codeword associated with the first codeword index value; and when a second coefficient of the transform unit has a second scan order value that is less than the threshold and when the second coefficient is the last significant coefficient in a scan order in the transform unit, the second scan order value representing a position of the second coefficient in the scan order:
executing a function, using the second scan order value as input to the function, to determine a mapping between data for the second coefficient and a second codeword index value, wherein the function outputs the second codeword index value, wherein the function maps different scan order values combined with the data for the coefficient to different codeword index values, and wherein executing the function comprises executing the function without accessing the codeword table, wherein the function is separate from the codeword table; andcoding the data for the second coefficient using a second codeword associated with the second codeword index value.