Method and systems for thumbnail generation, and corresponding computer program product

摘要

An embodiment of a consumer electronics product having a thumbnail display feature includes a system for generating and storing thumbnails having a given size from images, such as JPEG images, for which a spatial frequency domain representation is available. The system includes a zooming processor to reduce the size of the images by zooming. The zooming processor is configured to perform both spatial frequency domain zooming to approximate the desired thumbnail size and then image pixel domain zooming to fit the desired thumbnail size. The product includes cache storage configured to store a plurality of thumbnails in a file system as free blocks in the file system, so that file system data structures are left unchanged.

主权项

1. A method, comprising:
scaling an encoded image by changing by a first factor at least one dimension of transform-domain blocks that represent the encoded image; decoding the scaled encoded image into a decoded image; and scaling the decoded image by changing by a second factor at least one dimension of the decoded image; wherein scaling the encoded image comprises reducing by the first factor the at least one dimension of the transform-domain blocks, the at least one dimension being an integer multiple of the first factor.