| 20100046846 | IMAGE COMPRESSION AND/OR DECOMPRESSION - A method of image compression in which multiple versions of an image are compressed, each version having a different image resolution, comprises the steps of: for one or more compressed versions of the image: decompressing that compressed version to generate decompressed image data; detecting image differences between a higher resolution version of the image and the decompressed image data; and compressing difference data dependent upon the detected image differences. | 02-25-2010 |
