IMHO part of the challenge is the ID3 spec is very broad when it comes to Album Art, essentially supporting most anything as long as it's bounded by valid container tags. With all those possibilities, players will still never support every possible combination from past, present and future. I accept that.
Tesla of course has not specified what their design points or limitations may be -- we only found though usage that some Album Art is displaying when 8.0 was made available. As such, without any concrete evidence,
my gut remains convinced the failures I'm seeing with Album Art in 8.0 are due to some combination of these 3 things not being supported or mishandled with Tesla's initial Album Art implementation.
- Format: IMHO, a minimum of .jpg and .png file types need to be supported if they are not
- Physical Size / Dimensions: As in, if the aggregate image size (KB/MB) is too big and/or if dimensions of the art itself on one or more axes is too large from Tesla's design perspective, it may be ignored or mishandled -- IDK. My personal expectation would be Tesla should scale down anything that may be too large for it to use or display, never ignore something that is valid if that is what is happening.
- Multiple Album Art within a single track: ID3 spec (as well as iTunes and other prominent players) allow this, even if only the first image is ever displayed upon playback without the user taking overt action to see the others. Again, I'd expect Tesla to at a minimum do the same if they are not -- always show the first piece of valid Album Art and ignore the rest if they exist within a track.
Background:
In terms of Album Art, the majority of mine has been added over the years via simple drag and drop from one source on my former PC, now Mac, to the iTunes Album Art window for the Album (which propagates to each individual track). Most of my first 1000 or so albums were all manually ripped way back-in-the-day directly into iTunes, with my manually locating or scanning cover art before there was decent automation to assist in the selection process in more recent times. The remaining 300+ albums I have are digital downloads, but I've purposely scanned my entire library and replaced common iTunes-specific images via drag-and-drop into every track to ensure they had their own unique images in prep for my MS one day being able to display them.
Amazon is still generally my favorite go-to location finding large album art if I'm not using a tool like dBpoweramp to rip a whole CD. Amazon also has a mix of .jpg and .png file types, just as I have in my library. For the past at least couple of years, I have been trying to put art in place with a
minimum 800x800 size, but most new Albums from say Amazon are in excess of 1000x1000 these days. I also have a fair number of albums, and therefore tracks, where I have scanned jackets and liner notes that come with CDs, and placed each image as additional album art on the tracks so I'm 100% digital.