Patent ID: 8306350

Claim:
A method for scaling an image input pixel grid having a given aspect ratio to an image output pixel grid having a different aspect ratio, comprising: receiving input pixels from a video source; determining an input position count value for each input pixel representing a numerical position of that input pixel in relation to the beginning of an input line; determining an output position count value for each output pixel representing a numerical position of that output pixel in relation to the beginning of an output line; determining an alignment count value for alignments of input pixels on the input pixel grid with output pixels on the output pixel grid; determining a position dependent scale factor for each input pixel based on a comparison of input position count values of input pixels, the output position count values of neighboring output pixels, and the alignment count value; determining that an output pixel should be outputted based on the count value comparison; centering a polyphase finite impulse response filter on a particular input pixel based on the count value comparison; generating an output pixel using the polyphase finite response filter on a particular input pixel based on the count value comparison; and outputting the output pixels; whereby the position dependent scale factors provide output pixels corresponding to input pixels at a unity scale factor at a center of the image output pixel grid, at one of a maximum or minimum scale factor at edges of the image output pixel grid, and at a scale factor increasing or decreasing on a pixel-by-pixel basis from the from unity to one of the maximum or minimum scale factor between the center and the edges.