Scheme Editing

A saving scheme is a set of parameters describe how the program will process your photos. It is consisted of two parts, JPEG settings and limitations. The JPEG parameters decide the first try of saving. After that, the program will check the result with the conditions in 'limitations' part. If NOT pass, find best trade-off as the way you specified.

JPEG Settings

Quality: The higher quality brings less noise and distortion but larger file size; in contray, a smaller number means smaller file size but worse quality.

Highquality color: In default, JPEG will compress chroma channel more than luminance channel. Which will brings higher compression ratio with unnoticeable quality loss. But in some case this will blur the edge of sharp red objects, e.g red text or stamp. Check this option to avoid it or check 'Auto' to find out whether the current photo need or not.

Try to compare:
Normal JPEG
Highquality Color

Include EXIF: The EXIF information will cost 2-15KB of file size. You can uncheck it to save more.

Adaptive Quantification: Use adaptive quantification table instead of standard JPEG table. This option may improve compression ratio alot, but may brings noticeable noise. Check it when small file size is very important than quality.

Optimize More: Try to compress more at the area where hard to be noticed by human eye.

Blur: Blur image before compressing to get higher compression ratio.

Limitations

Image Size: Set image size limitation here.

File Size: Set file size limitation here.

Trade off rule: If file size exceed limits, you should either select shrink image size or low down quality.The program will do this automatically for you., and find out the best trade off point for you.

Typical Settings

Save with maximal quality under a file-size limit:
Set Quality to a high level (e.g. 95), set file size limits, and a reasonable image size, normally, let predicted compression ratio under 12:1 ( Imagesize*Imagesize*3 = 10 * Filesize * 1024 ). Set 'trade-off' to 'Decrease JPEG quality'.

For this kind of setting, normally the first saving try will exceed file-size limit, then the program will find a lower quality in which the output precisely under expected file size. And this quality is the maximal quality you can get under current settings.

Refer to presetted scheme: 'maxQuality.L1024px.230K';

Save with maximal image-size under a file-size limit:
Set Quality to a acceptable level (e.g. 85) , set file size limits, and 'trade-off' to 'Shrink image size' .

Refer to presetted scheme: 'maxImageSize.Q85.100K';

Set for one web site:
For examplt, www.photo.net require the long dimension of photos under 1024 pixels, and the file-size for 1024px photo normmally is 230K, we set the condition into limitations, ans save it to scheme. Refer to 'Site.photo.net.L1024px.Good'.