Custom Quality Factor.

Size more important than quality (less tiling)

This option produces less tiling in the image than the previous options. However, it may distort some text or straight lines. It is a good option for image database applications.

Maximum compression

This option gives maximum compression. It is equivalent to a Q factor of 255.

Maximum compression keeping quality

This option provides maximum compression while maintaining as high as possible image quality.

Perfect quality 1

This option compresses all colors of a 24-bit file and maintains the quality of the original image at a smaller file size. As the name suggests, there is no visual loss of color at this setting.

Perfect quality 2

This will produce a smaller file size than PQ1 while maintaining similar quality.

Quality more important than size

While more colors are removed, most of them are colors or shades that are close to one another. The compressed image will appear very much like the original image. It will take some study to see the difference.

Quality and size equally important

This option provides the highest compression while maintaining good image quality. Try this option first, then move up or down the list accordingly to obtain acceptable compression size and image quality.

Size more important that quality (sharp)

This option is recommended for images that have sharp edges. For example, an image that has a text overlay or an image with many straight lines. While it creates a larger file than the next option, it retains better edges.

Quality far more important than size

This option removes colors not noticed by the human eye. Most viewers cannot tell the difference between an image compressed at this level and the original image.