Patent ID: 7750979

Claim:
In a video processing circuit having an input stream of pixels corresponding to an array of video pixels, having a variable window size for sampling subsets of the array as a two-dimensional window that spans the pixels in the array, having a video processing stage that inputs pixels using a fixed number of pixels, a method for delivering the input stream of pixels to the video processing stage, the method comprising: establishing a window size and a sampling-window size, such that the window size is a multiple of the sampling-window size and the sampling-window size defines the fixed number of pixels; and concurrently storing pixels from the input stream into a first set of line buffers, the pixels stored in the first set of line buffers including pixels for the established window size, prefetching the stored pixels from the first set of line buffers into a second set of line buffers, the second set of line buffers being sufficiently long to store at least the pixels corresponding to the established sampling-window size, and for the video processing stage, fetching the fixed number of pixels from the second set of line buffers.