An encoding method and apparatus uses energy characteristic of discrete cosine transform (DCT) domains for determination of a quantization level. The DCT domain is divided into for sub-domains. The energy characteristic of each macroblock is represented as one among the four domains such as simple, complicated,...http://www.google.se/patents/US5489944?utm_source=gb-gplus-sharePatent US5489944 - Encoding method and apparatus to determine quantization levels using energy characteristics in the DCT domain
