2.4 File Formats and Compression
Depending on the contents of your documents, basically, we can classify them into three image types.
2.4.1 File Formats
Determine the kind of information to be saved in a file, the compatibility with various software applications and the exchanging of data in the production process. There are some influential factors in saving a scanned image. What program you'll use to post-process the image? How much disk storage is available? Will you exchange the file with others during production process and the eventual output mediums?
Please refer to the following table.
|File Format||File Extension||Recommended
|PCX||.pcx||Multimedia, Presentation, Video||Used by most software application.|
|PICT||.pict, pct||Multimedia, Presentation, Video||
|BMP||.bmp||Multimedia, Presentation, Video||
|Targa||.tga||Multimedia, Presentation, Video||
|JPEG||.jpg||Multimedia, Presentation, Video||
If the 2:1 compression ratios are not high enough, lossy compression has to be considered, the most popular lossy compression option is JPEG, JPEG stands for the Joint Photographic Experts Group, which developed the compression standard JPEG compression ratios are user selectable in the host software and range from 2:1 to about 40:1.