@mbrett You can use lr-vice instead and use RetroArch's built-in Save State function to accomplish the same thing tho.
lr-vice is maybe slower than standalone, I dunno, but on my Pi4 I can't see a performance difference.
Thanks, these are just the features that I missed in raspi2png, especially the incremental file naming.
@Pupsenlalala I see UXS populated your <Video> tag... but with a wrong extension. (jpg)
Try to put "Default" in Configuration/Advanced/Image configuration Menu.
It will solve your problem.
(Need to put that on default config :S )