| 摘要 |
An image processing system stores image files in a memory device at a number of incremental quality levels. Each image file has an associated image quality (that is fidelity or resolution) level corresponding to a quality level at which the corresponding image has been encoded. The images are initially encoded by applying a predefined transform, such as a DCT transform or wavelet-like transform, to image data received from an image capture mechanism and then applying a data compression method to the transform data. The image is regenerated by successively applying a data decompression method and an inverse transform to an image file. Image file size reduction circuitry and one or more state machines are used to lower the quality level of a specified one of the image files, including circuitry for extracting a subset of the data in the specified image file and forming a lower quality version of the specified image file that occupies less space in the memory device than was previously occupied by the specified image data structure. As a result, the amount of space occupied by image files in the memory device can be reduced so as to make room for the storage of additional image files or to allow more rapid transmission in a restricted bandwidth environment. |
