摘要 |
A method for resizing an original image using the inverse discrete cosine transform (IDCT), wherein the original image is divided into image blocks and each of the image blocks is discrete cosine transformed, comprises the steps of: (a) receiving discrete cosine transformed image blocks of size M x N from a digital broadcast or a data stream reproduced from a storage medium; (b) determining the size P x Q to which each of the discrete cosine transformed image blocks is to be enlarged and appending rows and columns of zeros to the high frequency area of each of the discrete cosine transformed image blocks so that the size of each of the discrete cosine transformed image blocks becomes the determined size P x Q; (c) computing a k-coefficient for the zero-appended discrete cosine transformed image blocks and multiplying each of the zero-appended discrete cosine transformed image blocks by the k-coefficient; (d) performing inverse discrete cosine transform (IDCT) operations on the zero-appended discrete cosine transformed image blocks multiplied by the k-coefficient to produce enlarged image blocks of size P x Q; and (e) producing an enlarged image by combining the enlarged image blocks of size P x Q, wherein the number of rows of each of the image blocks is determined by choosing a common divisor of the numbers of rows of the original image and an enlarged image to be produced and dividing the number of rows of the original image by the chosen common divisor and the number of columns of each of the image blocks is deter-mined by choosing a common divisor of the numbers of columns of the original image and the enlarged image and dividing the number of columns of the original image by the chosen common divisor. |