1. A method of scaling a composite overlay image and a background image in a computing device, wherein the composite overlay image comprises a plurality of pixels in a buffer memory and each pixel comprises at least one color channel and at least one alpha channel, said method comprising an image processor: (a) identifying a set of pixels of the composite overlay image, wherein at least one pixel of the composite overlay image has an alpha value of zero and a color value that is not well defined, said identifying comprising: (i) creating a binary alpha representation in the buffer memory corresponding to the composite overlay image; (ii) storing information in the binary alpha representation that is representative of the alpha channels and their corresponding pixel position in the composite overlay image; (iii) dilating the binary alpha representation to form a dilated alpha representation in the buffer memory; (iv) subtracting the binary alpha representation from the dilated binary alpha representation to form a subtracted binary alpha representation in the buffer memory; (v) identifying each of the binary values stored in the subtracted binary alpha representation that represent a non-zero alpha value and the corresponding position information; and (vi) identifying each of the overlay pixels corresponding to the position information identified in (v) as pixels to be dilated; (b) dilating the color channels of the identified pixels to form a dilated composite overlay image in the buffer memory; (c) scaling the dilated composite overlay image to form a scaled dilated composite overlay image in the buffer memory; (d) scaling the background image to form a scaled background image in the buffer memory; and (e) combining the scaled dilated composite overlay image with the scaled background image to produce a combined image in the buffer memory.