Fast Inter-Mode Decision Algorithm for P Slices in H.264/AVC Video Standard

We propose a fast macro-block (MB) mode prediction and decision algorithm based on temporal correlation information for P-slices in the H.264/AVC video standard. There are 8 block types for temporal decorrelation including SKIP mode exist based on rate-distortion (RD) optimization. This scheme gives rise to exhaustive computations (search) in the coding procedure. To reduce this computational load, a thresholding method for fast inter mode decision using a MB tracking scheme to find the most correlated block and RD cost of that is suggested for early stop of the inter mode determination. Firstly, an inter mode candidate selection method is suggested through the statistical analysis. Then an adaptive inter mode search algorithm is applied by using RD cost of the most correlated MB. Through comparative analysis, a speed-up factor of up to 70.59% was verified with a negligible bit increment and a minimal loss of image quality.