A Fast Intra Prediction Algorithm for H.264

Intra prediction applied in H.264 improve compression efficiency greatly of I frame. But the full search algorithm is computationally expensive and there exist conflict with some real time application and embedded systems just holding limited calculation resource. In order to promote prediction speed, a fast intra prediction algorithm is proposed which select appropriate intra prediction type based on complexity of the macroblock, use the difference between neighbor block´s gradient vector and neighbor block´s most optimization´s direction to select current block´s prediction mode. Experiment results show that this new proposed algorithm greatly improves the speed of Intra prediction with negligible PSNR degradation and increment of bite-rate.