Hi there,

There's several animations on Tumblr that I would like to upload here but they're in .mp4. Is there any viable way to convert .mp4 to .webm without compression/pixelation?

Thanks!

Simple answer: you can't. Both MP4 and WebM are lossy formats, so converting one to the other always means quality loss.

Upload the best WebM you can make, but leave the original MP4 in the source list so people can find it if they want to :)

canadianmoose said:
Hi there,

There's several animations on Tumblr that I would like to upload here but they're in .mp4. Is there any viable way to convert .mp4 to .webm without compression/pixelation?

Thanks!

Check out Mairo's profile; they talk about conversion and the like, and they even helped me out quite a bit with conversion stuff!

Also, @Mairo (just in case you have anything else you might want to offer here in this thread)

BlackLicorice said:
Simple answer: you can't. Both MP4 and WebM are lossy formats, so converting one to the other always means quality loss.

Upload the best WebM you can make, but leave the original MP4 in the source list so people can find it if they want to :)

Pretty much this. Almost all video files you can aquire online are using lossy codecs, meaning lossy -> lossy is always... lossy.

As long as the quality is as close to original as possible without spending 100 MB in 2 seconds of video, that's usually more than fine. Using constant quality mode with CRF of 12-18 (lower=better quality) has proven to usually hit that sweet spot.
https://trac.ffmpeg.org/wiki/Encode/VP9
(VP9 does have lossless mode, but this isn't useable with streaming the video like being embedded to e621)

Also make sure you are always getting as high quality file as possible to do the conversion from to avoid further degradation, with tumblr this means making sure that the filename doesn't have _480 or _720 in it.
howto:sites_and_sources#tumblr

Also that's good mention, providing all and every link that artist has given is always good idea, original MP4 in source gives users ability to download original copy and something like gfycat links in description help iOS users (because apple is using their customers as their weapon to force their own media formats to be more popular, thus not supporting alternatives like webm).

Great, thanks folks.