US Patent 7634526 Selectable quantization in an encoder

A method for selectable quantization for use in an encoder for compressing video and/or audio data includes processing that begins by receiving discrete cosine transform data of an encoded signal. The processing continues by generating a plurality of quantization matrixes of discrete cosine transform data based on a quantization table and a plurality of quantization scaling factors. The process continues by analyzing the plurality of quantization matrixes to identify one of the plurality of quantization matrixes having a best match of reduced data content and acceptable video quality. The processing continues by selecting the one of the plurality of quantized matrixes.