Most digital cameras store thumbnails (small preview of the image - the usual size is 160 x 120 pixels, file size approx. 10KB) directly in JPEG files. They enable very fast viewing of image file thumbnails (see Selecting Current View in panel) because it is not necessary to read entire images and downsize them to thumbnails.
Unfortunately some image editors do not respect thumbnails stored in images, so when you change (or rotate or crop) the image in such editors, they simply copy the original unchanged thumbnail (you see out-of-date thumbnail) or ignore thumbnails entirely (slow getting of thumbnail). In both cases you can use PictView to update the thumbnail stored in the image file.
To update a thumbnail inside a JPEG file:
- Select one or more files in which you want to update the thumbnails.
- Start updating of thumbnails:
Menu: Plugins/PictView/Update Thumbnail