05-05-2020, 09:53 PM
(05-05-2020, 08:59 PM)suzywong Wrote: One of the things I’ve noticed since 6.5 relates to the old “update thumbnail cache” function on the Library Configuration page, which was removed when the “update library now including update thumbnail cache” function was moved to the top level drop down menu (of which I heartily approve!).
I’ve been “amusing” myself during retirement and lockdown by editing and correcting metadata for my NAS database; mostly this has involved merely updating album covers. The editor I have been using is MP3Tag. What appears to happen if I just change a cover picture, is that the “update library” function does not pick up the change. And yes, I have tried clearing the thumbnail cache, etc etc after each “update library”.
My only recourse is to perform a full “regenerate thumbnail cache”, then clear the cache and reload the library. I don’t recall this being an issue in 6.4.x, when I could use the now defunct “update thumbnail cache” to quickly update the thumbnails after editing.
To be sure, this is not a huge issue, and once I have completed my update of the whole datebase (doing the “J”s at the moment), then it should not be an issue, and the “update library” function will come into its own.
However, I contend that the stand-alone “update thumbnail cache” function did/would, in fact, serve a useful purpose in 6.5.x, and should be restored to the Library Configuration page.
It can be confusing but the thumbnail generator creates the thumb image filename based on a hash of the path to Album directory. When it runs it hashes each path in the input directory listing and then checks to see if a hash.jpg already exists in the thumbnail cache. If it does it skips to the next path.
What this means is that its Update mode is actually only able to add new thumbnail images not replace existing ones. The Regenerate mode simply deletes the thumbnail cache so that all new thumbnail images are created.
You might ask why is it done this way. The answer is that this particular approach allows the client to instantly obtain the hash of the thumbnail image for display by simply hashing the path string. If the entire image file had to be hashed there would be performance issues.
I'm sure there are other approaches to doing this kind of thing and I'd certainly be interested in any contributions to the subject.
