image-dired-thumb-name
image-dired-thumb-name is a compiled Lisp function in `image-dired.el
'.
(image-dired-thumb-name FILE)
Return thumbnail file name for FILE.
Depending on the value of `image-dired-thumbnail-storage', the file
name will vary. For central thumbnail file storage, make a
MD5-hash of the image file's directory name and add that to make
the thumbnail file name unique. For per-directory storage, just
add a subdirectory. For standard storage, produce the file name
according to the Thumbnail Managing Standard.