Under options MENU>OPTIONS>COVER ART>COVER ART PROVIDERS
I see a list (6) providers.
If you select all (6) does this slow down the processing of tags? Do you need to select more that one provider? Does MBPicard default in a daisy-chain referral to the next provider if it comes up empty?
Say my session crashes and the next time I restart and upload the same folder for processing, does MBPicard re-upload the images again making the process slow? IS there a way that MBPicard can embed the artwork so that it speeds up the music tag processing on the 2nd reload of the same folder?
I checked the option Embed only a single front image because I want to speed up the processing of music tags. Is the the correct thing to do? SHould I also check Embed cover images into tags to speed up processing? Does checking the box Save cover images as separate files speed up processing and prevent MBPicard from re-uploading the cover art again?
You are causing chaos by trying to do everything at the same time… your current tactic of turning everything on will end up with crashing and a mess of data that will not make sense. Get the tags sorted. Do art another day.
Yes, it will work through the list in order. If no art is found, it moves to the next. BUT if you go tag the files first, then return later to add the artwork, then this is all much quicker.
Embedding artwork will clearly be slower that saving a cover.jpg.
Picard will apply the cover art providers in order from top to bottom. As soon as one provider gets a result it stops. One way to that sometimes can speed the loading of already tagged files up is moving the local files provider to the very top.
As @IvanDobsky wrote above embedding cover art can slow down saving the tags, in some cases significantly. The reason is that cover art is a large chunk of data that often does not fit into the existing space available for tags in the files. This causes the entire file to get resaved. Especially for larger files (e.g. FLAC) on a slow storage (e.g. network drive) this can be very slow.