35mm Movie Trailers Scans

Looking for a solution to a problem with YouTube uploads.

Download this file to see the problem: we.tl/t-3XOo16OmDV (link expires on March 4th 2024)

I recently started using vp9 as an encoder for the video I wish to send to YouTube. In the present zip file you can find the file I sent: "whatISentToYoutube.webm" which visual qualities are super great for the mere 4.8Mb/s bitrate I chose to match YouTube's logic . After upload to YouTube. When I later on watched the video on their platform I deadfully noticed a stutter in the picture, especially with the slow and medium pans.

I downloaded the high resolution vp9 from Youtube using:
yt-dlp_linux -o whatCameBackFromYoutube.webm -f 313 https://www.youtube.com/watch?v=y57ol...
and I compared the ffprobe video outputs of both my file and theirs:
-------------------------------------------------------------------------------
Input #0, matroska,webm, from 'whatISentToYoutube.webm':
Metadata:
COMPATIBLE_BRANDS: qt
MAJOR_BRAND : qt
MINOR_VERSION : 512
ENCODER : Lavf59.27.100
Duration: 00:02:33.67, start: -0.007000, bitrate: 4829 kb/s
Stream #0:0: Video: vp9 (Profile 0), yuv420p(tv, bt709/bt709/unknown, progressive), 3072x1320, SAR 1:1 DAR 128:55, 24 fps, 24 tbr, 1k tbn (default)
Metadata:
HANDLER_NAME : VideoHandler
VENDOR_ID :
TIMECODE : 01:00:00:00
ENCODER : Lavc59.37.100 libvpx-vp9
DURATION : 00:02:33.674000000
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
:Input #0, matroska,webm, from 'whatCameBackFromYoutube.webm':
Metadata:
ENCODER : Lavf59.27.100
Duration: 00:02:33.68, start: -0.007000, bitrate: 4832 kb/s
Stream #0:0(eng): Video: vp9 (Profile 0), yuv420p(tv, bt709), 3072x1320, SAR 1:1 DAR 128:55, 24 fps, 24 tbr, 1k tbn (default)
Metadata:
DURATION : 00:02:33.666000000
Stream #0:1(eng): Audio: opus, 48000 Hz, stereo, fltp (default)
Metadata:
DURATION : 00:02:33.681000000
-------------------------------------------------------------------------------

So even if my encoder was vp9 and my bitrate was even lower than theirs, they re-encoded it and, somehow, they found a way to totally mess it up.

Here are the equivalent of the ffmpeg encoding commands I used to create "whatISentToYoutube.webm":
ffmpeg -i "HighBitrateHQX_350Mbps_10bits_Video.mov" -vf "yadif,format=yuv420p" -c:v libvpx-vp9 -vb 4800k -pass 1 -passlogfile "tmpfile.log" -acodec libopus -ab 128k -f null "/dev/null"
ffmpeg -i "HighBitrateHQX_350Mbps_10bits_Video.mov" -vf "yadif,format=yuv420p" -c:v libvpx-vp9 -vb 4800k -pass 2 -passlogfile "tmpfile.log" -acodec libopus -ab 128k "whatISentToYoutube.webm"

Here are the questions:
-What causes the stuttering on their version of the video?
-Am I the only seeing the stuttering?
-Can I avoid them from stuttering by adding some options to my encoding?
-Should I refrain myself from ever using vp9 myself? (and stop suffering with the huge encoding time) and send them a high bitrate version instead to let them deal with it?

1 year ago | [YT] | 10