3. The system of claim 2 , wherein the video coding complexity engine further comprises a feature extraction module configured to extract spatial and temporal features of the source video, wherein the spatial features of a frame of the source video represent the spatial activity of the frame, and the temporal features of a frame of the source video represent the amount of motion in the frame.
3. The system of claim 2 , wherein the video coding complexity engine further comprises a feature extraction module configured to extract spatial and temporal features of the source video, wherein the spatial features of a frame of the source video represent the spatial activity of the frame, and the temporal features of a frame of the source video represent the amount of motion in the frame. 4. The system of claim 3 , wherein the spatial activity of the frame is represented by at least one of the variance of luminance value of each macroblock of the frame averaged over the entire frame, and the energy of motion-compensated luminance residual averaged over the entire frame.