FFmpeg metadata tags for YouTube 3D side-by-side movies

Question

YouTube requires specific metadata tags for 3D Side-By-Side format movies. If the tag is not there then YouTube does not give the anaglyph playback options for the end user.

Their "help" is here https://support.google.com/youtube/answer/7278886?hl=en-GB

I am trying to get FFmpeg to add the MP4 tag when building my movie.

Code that works now for a series of PNG files into a MP4.

"ffmpeg.exe" -framerate 60 -i "VID%05d.PNG" -c:v libx264 -preset:v veryslow -profile:v high -crf 15 -s 1280x720 -pix_fmt yuvj420p -an -y "OUTPUT.MP4"

But when I add the tag from the YouTube help page

"ffmpeg.exe" -framerate 60 -i "VID%05d.PNG" -c:v libx264 -preset:v veryslow -profile:v high -crf 15 -s 1280x720 -pix_fmt yuvj420p -an -y -x264opts "frame-packing=3:frame-packing-interpret=1:frame-packing-quincunx=0:frame-packing-grid=0,0,0,0" "OUTPUT.MP4"

I get this error from FFmpeg

[libx264 @ 0000000002a8c3a0] bad option 'frame-packing-interpret': '1'

This page (ignore the proselytising)

http://www.pantherdynamics.yolasite.com/panther-dynamics-blog/uploading-3dsbs-content-to-youtube

says you only need to use this tag

-x264opts frame-packing=3

Using that does make FFmpeg finish correctly, but the SBS is still ignored by YouTube

The YouTube engineer blog post here

https://youtube-eng.googleblog.com/2011/09/getting-3d-content-on-youtube_8.html

links to an older supposed 3D movie that also does not give 3D options any more.

https://www.youtube.com/watch?v=ubRHSg5daMs

So maybe even YouTube's own 3D movies are crippled?

What am I doing wrong? Any FFmpeg gurus able to help?

Answer 1

stereo_mode=1 is wrong for MKV. use left_right instead.

I know that's still on the YouTube advice page, but it's wrong (I uploaded both to YouTube yesterday and only left_right works). That's why some people think YouTube have dropped support for MKV 3D, it still works as of today.