Quantization offsets for video coding

In this paper we propose a modification in the H.264/AVC quantization scheme for transform coefficients. This modification is based on a simple offset that provides a more accurate adjustment of the quantizer, especially of the dead-zone size, to the signal statistics. Compared to a deadzone adjustment that is H.264/AVC compliant, the proposed modification improves the coding efficiency and the subjective picture quality. Although there are several other applications that would benefit from the proposed quantization offset, the experimental results in this paper are restricted to coding of HD movies that contain film grain. A quantizer modification for such high quality consumer applications leads to significantly improved subjective picture quality.