Patent ID: 7084889

Claim:
A method for scaling a digital picture comprising the following steps: (a) inputting a source picture to a source memory; (b) providing a first buffer and a second buffer; (c) determining scaling factors; (d) generating initial data in the first buffer and second buffer; (e) transferring a portion of data of the digital picture from the source memory to the first buffer, the portion of data having a size in a second direction of L and size in a first direction equal to a corresponding size of the source picture; (f) using an L-tap filter to scale the data in the first buffer in the first direction and storing the scaled data in the second buffer; (g) using the L-tap filter to scale the data in the second buffer in the second direction and storing the scaled data in a destination memory, the scaled data having a size in the first direction of 2*L−1; (h) for each different portion of data in sequence, repeating steps (e) through (g) to form a scaled picture; and (i) outputting the scaled picture from the destination memory.