Because of the first filename (stp_meadow_single_puzzle_v1.j pg), I previously thought this meant it was the cover for the first single.
Now I think the “single” in the filename referred to a single puzzle piece, not the first single (song). So now, I think it is the cover for the album, and the album must have “meadow” in the title somewhere.
Edit: Because it looks like a yellow brick road, I searched “Wizard of Oz meadow” and this it what came up: http://oz.wikia.com/wiki/Poppies
(It’s possible it has nothing to do with this, but it’s kinda fun to speculate.)
Honestly never thought single meant anything other than "single puzzle piece". Can't imagine they'd put a countdown to the cover art for a single, especially in a day and age when singles are almost always digital.
As for "meadow", I honestly doubt it has anything to do with the album title. I think since the image is of a yellow-brick road heading from mountains into a sunny MEADOW, they simply named the image file meadow. If it had been Purple's cover it would be called "dragon", if it were No. 4 it would be "star", if it were Thank You it would be 'daisy'.
IMO, the file name tells us nothing.