Bug: TC writes thumbnail cache but never uses it

[ghisler(Author)]

I cannot reproduce that, the cache is used. The question is whether the thumbnails for these files are cached or not.The cache does not work in
- virtual folders
- folders containing some special characters, which are not supported in compound documents

Also thumbnails are not cached when extracting them takes a very short time.

[Hacker]

Christian,

- virtual folders
- folders containing some special characters, which are not supported in compound documents

Neither.

Also thumbnails are not cached when extracting them takes a very short time.

What is that time, please? I think I remember it being 0,5 seconds but if that would indeed be the case, that is too long.

With the new JPG thumbnail loading from EXIF, I get about 0,04 s per thumbnail, which is really fast.
Now imagine if I have to wait 0,4 s for video thumbnails, that is ten times slower and feels really frustrating, especially if it could be cached.

Could the delay be made configurable?

Thank you
Roman

[ghisler(Author)]

The limit is 50 milliseconds. Maybe some virus scanner is slowing down the loading from tcthumbs.db/tcthumbs.idb?

Btw, you can check with the plugin wcx_storage whether a specific image is stored in tcthumbs.db:
http://totalcmd.net/plugring/wcx_storage.html
You will need to open it with Ctrl+PageDown.
Some notes about the format:
1. The entry "Dimensions" in the root contains the width and height of the stored thumbnails.
2. The directories are stored in the form drive letter\directory\file name
3. Due to a limitation of the compound file format, If a file name is longer than 31 characters, it is split into multiple nested entries. Each part starts with a question mark. For example, the name
f:\images\20210601_test file with long name.jpg
is stored as
f\images\?20210601_test file with long n\ame.jpg
4. Thumbnails of folders are stored with a question mark at the end, so both the folder and its thumbnail can be stored.
5. Each entry is just 8 bytes long, 4 is the offset in the file tcthumbs.idb, and 4 is the length.
6 The file tcthumbs.idb contains at that offset the entry length, a signature, some flags, the file timestamp, and the compressed image data.