Cards images are gathered from wowcards.info, so all card names should match their format.
Some card names are not unique, such as some found in dungeon decks with gold bordered and black bordered versions. When collisions happen the black bordered cards are provided.
Deck images are put through a high JPEG compression compared to normal images, this is a because deck images are around 10 mega pixels with some decks requiring multiple images. In order to shorten download times in game, images are ran through either 50% or 80% compression, depending on your chosen settings. Below are examples of these images and their resulting sizes.
Tabletop simulator does similar compression after downloading the files, depending on your video settings the level 0 compression and level 50 compression will be identical. If you don't find this to be the case and want a very high quality that option has been provided.
File Size 1MB
File Size 1.7MB
File Size 9.6MB