Patent ID: 7876976
Filing Date: 2011-01-25
Classification: G06T,H04N

Abstract:
1. A method of resizing an image using a resizing ratio, comprising: receiving a DCT (Discrete Cosine Transform) coefficient matrix Y×X of an input image; calculating a transformation matrix for transforming the DCT coefficient matrix Y×X of the input image using an integer aspect ratio closest to the target resizing ratio; performing a coarse resizing on the DCT coefficient matrix Y×X of the input image in a DCT domain using the transformation matrix; obtaining a spatial image by performing an IDCT (Inverse Discrete Cosine transform) on the coarse-resized image; and forming an output image having a coefficient matrix y×x by performing a fine resizing on the spatial image in a spatial domain, wherein the calculating of the transformation matrix includes: Y denotes the number of pixels in a vertical direction of the input image, X demotes the number of pixels in a horizontal direction of the input image, y denotes the number of pixels in a vertical direction of the output image, an x denotes the number of pixel in a horizontal direction of the output image, and the performing of the coarse resizing includes calculating an N″×M″ transformation matrix of the input image using the N″×N″ transformation matrix and the M″×M″ transformation matrix.