Patent ID: 8218624

Claim:
A computer-implemented method of coding video using a video encoder, the method comprising: with the video encoder, encoding video to produce encoded data, including: selecting a scale for a quantizer from a set of values expressable via an encoding syntax, wherein step size increment between the expressable values varies within the set of expressable values depending at least in part on quantization step size, and wherein the selecting the scale for the quantizer includes: when coding at a high quantization step size, selecting the scale for the quantizer from among the expressable values at a full step size increment; and when coding at a low quantization step size, selecting the scale for the quantizer from among the expressable values at a step size increment that is a fraction of the full step size increment; and processing transform coefficients for blocks based at least in part on the quantizer with the selected scale; and outputting the encoded data in a bit stream, including: signaling the selected scale for the quantizer using a first syntax element that represents the full step size increment; comparing the selected scale to a comparison value to determine whether or not to signal a second syntax element that represents the fraction of the full step size increment, wherein the comparison value is 8; and if the comparison indicates the second syntax element is to be signaled, signaling the second syntax element that represents the fraction of the full step size increment.