The preferences menu is used to modify settings for each image that is processed with ClickPic. Most of these settings are discussed in the related sections, however the few that are not are discussed here.
JPG compression level is used to specify the amount of compression when saving a JPG image. JPG images are lossy, and therefore lose image data each time they are saved; that is why the compression levels are so good. Choose a higher quality for less noticeable compression effects at the expense of file size. Choose lower quality for smaller file sizes, though with more noticeble compression effects. This doesn't apply to lossless JPG rotations.
Selecting Preserve Image Metadata will preserve all tags and comments that are stored in some image formats. This is most useful for preserving digital camera EXIF information.
Image Preview Location allows the preview thumbnail to be shown in the main explorer menu, the clickpic menu, a submenu, or not shown at all. Turn this setting off for a faster right click menu as it takes a small amount of time to generate these preview images.
Image Preview Size allows the thumbnail preview image to size to be between 20 and 400 pixels in width and height.
For the other settings, see the relavent topics in this help file.