Sorry. I don't think I responded to this correctly before.
I think I tried exactly that based upon this stackoverflow question:
https://stackoverflow.com/questions/64981984/ffmpeg-transcode-uhd-h265-to-sdr-h264-without-color-loss
The example in that post uses this command:
|ffmpeg -i 4K.ts -vf
zscale=t=linear:npl=100,format=gbrpf32le,zscale=p=bt709,tonemap=tonemap=hable:desat=0,zscale=t=bt709:m=bt709:r=tv,format=yuv420p
-c:v h264 -crf 19 -preset ultrafast output.mp4 |
Which I thought might be my solution but when I tried it, it ended up
making the video too red.
Does that look like the route I need to take?
- Craig
On 3/25/21 4:09 PM, Pavel Koshevoy wrote:
On Thu, Mar 25, 2021 at 9:27 AM Craig L. <ffm...@trafficality.com> wrote:
I recently started finding certain videos were washing out upon H.264
conversion.
After doing some research I found that if I added -color_primaries
bt2020 to the command, the color would come out correctly, but ONLY if
the video was played in Quicktime. When played in Chrome, it would look
washed out.
Here is a link to a screengrab showing the video in quicktime on the
left and in Chrome on the right. Same video.
*https://snipboard.io/N8nYv0.jpg* <https://snipboard.io/N8nYv0.jpg>
After much research I can't figure out how to handle this?
What is the correct way to convert these videos that I suppose are 10
bit HDR into H.264 so that they will play correctly in Chrome, etc.
This is my current command:
/usr/local/bin/ffmpeg -i "156237-Video2.mov" -filter_complex
"scale=480:270" -color_trc smpte2084 -color_primaries bt2020 -c:v
libx264 -profile:v high -pix_fmt yuv420p -level 5.1 -preset ultrafast
-movflags faststart -vsync 2 -c:a aac -b:a 128k -y
156237-Video2.mov-16-9-1616621202.mp4
For best possible player compatibility you really need to convert from
HDR10 to SDR (bt709).
To do that you need to use either colorspace or zscale ffmpeg filter. The
colorspace filter didn't support HLG the last time I checked, but that
wouldn't matter if your source is HDR10, not HLG.
Since you'd be converting from high dynamic range to standard dynamic range
you would also need to use the tonemap filter.
There is probably a LUT file somewhere that implements HDR10 -> BT709 color
space conversion and tone mapping in one step, skipping zscale/tonemap. If
you had such LUT you could use it with lut3d filter.
Pavel.
_______________________________________________
ffmpeg-user mailing list
ffmpeg-user@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-user
To unsubscribe, visit link above, or email
ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
_______________________________________________
ffmpeg-user mailing list
ffmpeg-user@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-user
To unsubscribe, visit link above, or email
ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
