| 摘要 |
An image 200 is generated at a first resolution and if the first resolution exceeds a predetermined resolution, an image 210 at a second, lower, resolution is produced for transfer to a client. The invention is directed towards viewing of computer files on PDA's, mobile phones, etc. Images of the computer files are produced at a first resolution which is much higher than the resolution capabilities of such mobile devices. The images are then generated at a lower resolution which is capable of display on such mobile devices prior to transmission to said device. Dependent claims detail how the image may be viewed on the mobile device at higher resolution by selection of a portion of the low resolution image using a viewport, the corresponding portion 220 of the higher resolution image ten being transmitted at the higher resolution for display on the mobile device. An independent claim is also provided to a client arranged to receive an image of a file at a first resolution, and to further receive portions of a second image of the file, said second image having a higher resolution than the first resolution. |
