Patent ID: 7646815

Claim:
An apparatus comprising: A first processing circuit configured to generate a plurality of reconstructed samples in response to a plurality of neighboring macroblocks of an input signal; and A second processing circuit configured to: determine an intra prediction chroma mode 0 from a plurality of intra prediction chroma modes; generate a plurality of sum values S 0 , S 1 , S 2 and S 3 based on said reconstructed samples for a current chroma block said sum values being used in a plurality of formulas; and determine a plurality of intra prediction chroma mode 0 predictions A, B, C and D for said current chroma block wherein in a first case when only said sum value S 0 is unavailable, said intra prediction chroma mode 0 predictors are generated using the formulas A=(S 2 +2)/4, B=(S 1 +2)/4, C=(S 3 +2)/4 and D=(S 1 +S 3 +4)/8.