[X] My Assistant

I'm currently in the process of creating a gallery of animated Game CG WEBPs converted from MOV file outputs of the 2D animator software Spine. Any advice you can give me on keeping the final products within 20MB with as much quality and framerate maintained as possible? My MOVs are transparent 1280x720 60fps videos that range within at least 4 seconds of runtime, and even with ffmpeg's lossy WEBP conversion (-q:v 100 -compression_level 6), the resulting WEBPs end up going over the 20MB requirement.

I've never dealt with .mov files, but typically with ffmpeg doing two passes helps a lot with maintaining quality, and/or reducing the file size without lessening the quality as much.

I've never dealt with .mov files, but typically with ffmpeg doing two passes helps a lot with maintaining quality, and/or reducing the file size without lessening the quality as much.

My current workflow is this:
1.) Export the Spine animations as 3500p MOV files to avoid aliasing issues as much as possible. Working on anything beyond 4000p kills my laptop due to its limited 4GB RAM getting overloaded during Step 2.
2.) Shrink down the initial exports to 720p with a one-pass automated batch script for FFmpeg.
3.) Create WEBPs of varying FPS to check how high I can get them while staying within gallery limitations with another one-pass automated batch script for FFmpeg.
4.) Repeat for next scenes.

Should I be doing two-pass when I do Step 2, when I do Step 3, or when I do both?

Upload one of the mov files and the result you get, then its easier to tell where it can be further improved.

This post has been edited by -terry-: Feb 24 2025, 20:29

My current workflow is this:
1.) Export the Spine animations as 3500p MOV files to avoid aliasing issues as much as possible. Working on anything beyond 4000p kills my laptop due to its limited 4GB RAM getting overloaded during Step 2.
2.) Shrink down the initial exports to 720p with a one-pass automated batch script for FFmpeg.
3.) Create WEBPs of varying FPS to check how high I can get them while staying within gallery limitations with another one-pass automated batch script for FFmpeg.
4.) Repeat for next scenes.

Should I be doing two-pass when I do Step 2, when I do Step 3, or when I do both?

At least step 2, because there you're rescaling things. Maybe 3 too, honestly I've never been in a situation where I had a set file size and was trying to reach it by controlling FPS, so I'm not sure how ffmpeg handles that situation and how it differs with 1/2-pass. Is it readjusting the frames or just dropping frames? I don't know. Either way I doubt it makes anywhere nearly as much of a difference as step 2.

Also what Terry said.

This post has been edited by kotitonttu: Feb 25 2025, 19:45

WebP does not support inter-frame compression therefore file size will be huge.
Best way to reduce file size without losing in quality is to lower your framerate.
As an advanced way of reducing size i could give you one idea. WebP frames can be set with different delays, so in theory you could selectively reduce "framerate" for each part of the video, where its needed. But a file size of webp will always be like 100 times of something like webm with the same framerate and quality.

WebP does not support inter-frame compression

What? What a great format. I'm loving it more each time I learn more about it.

Is there absolutely no way you can get more RAM on your laptop? 4GB is really not a lot in 2025 and I can't imagine a (presumably DDR3/DDR4) SODIMM would be super expensive. Furthermore, is there no format you can use other than WebP?