Windows Thumbnail Cache
Vorlage:Unreferenced On Microsoft Windows operating systems, a thumbnail cache is a file used to store thumbnail images for Windows Explorer's thumbnail view. This speeds up the display of images as the smaller images do not need to be recalculated every time the user views the folder.
Purpose
Windows stores thumbnails of graphics files in the Thumbnail Cache file, including the following formats: JPEG, BMP, GIF, TIF, PDF, and HTML. Each thumbnail created in a directory is represented in this database file as a small JPEG file, regardless of the file's original format. Each folder with initiated thumbnail views (that is where they have displayed a Thumbnails or Filmstrip view in Windows Explorer) will have a Thumbs.db file.
Thumbs.db
Thumbs.db files are stored in each directory that contains pictures or movies on Microsoft Windows NT versions prior to Vista. The file creates locality among images, however, it prevents system wide use of the data.[1]. Windows XP Media Center Edition also creates ehthumbs.db which holds previews of video files.
Thumbcache
Beginning with Windows Vista, thumbnail previews are stored in a centralized location on the system. This provides the system with access to images independent of their location, and addresses issues with the locality of Thumbs.db files. The cache is stored at %homedrive%\Users\%username%\AppData\Local\Microsoft\Windows\Explorer as a number of files with the label thumbcache_xxx.db (numbered by size); as well as an index used to find thumbnails in each sized database. However, when browsing network shares with write permission, Windows Vista SP1 stores a Thumbs.db file in the remote directory instead of using the (local) central thumbcache.Vorlage:Fact