What are some alternatives?
When comparing ImageGlitcher.com and Tumblr Music Video Generator, you can also consider the following products
Photomosh - Turn anything into a vaporwave
Glitchatron - Destroy your favorite photos
MVGEN - Make your own music videos with audio, gifs, and special effects
HearSeeParty - Combine Gifs with with music using tags
Decim8 - Turn photographs into glitch art
VOCHI Video Effects - Mobile video editor that lets you apply video effects to single objects.