"Restore SDR" or "Remove HDR" its possible?

[danfgtn]

Hello everyone!

I really dont like the idea of hdr, some things do not have an option without hdr and this should get worse over time. So I wanted to know, is there any way to "remove" hdr from a video? Or some way to "restore" the original video color without hdr? I think I'm probably talking nonsense, but if the method exists, it would be great for me.

[pandy]

For example https://stevens.li/guides/video/converting-hdr-to-sdr-with-ffmpeg/

[danfgtn]

For example https://stevens.li/guides/video/converting-hdr-to-sdr-with-ffmpeg/

Thanks for the answer, I found some other threads here only after I had opened this, I should have searched more before.

[fornit]

I've recently found an interesting suggestion of Google to convert HDR to SDR using a LUT:
https://developers.google.com/media/vp9/hdr-encoding/

Search the page for:
"Converting HDR to SDR"

They do it for VP9, but it also works for AVC/HEVC. To be able to let it run, you must download the LUT file from:
https://storage.googleapis.com/media.webmproject.org/devsite/vp9/input/hdr/bt2020_to_b...9_example.cube

[pandy]

I've recently found an interesting suggestion of Google to convert HDR to SDR using a LUT:
https://developers.google.com/media/vp9/hdr-encoding/

Search the page for:
"Converting HDR to SDR"

They do it for VP9, but it also works for AVC/HEVC. To be able to let it run, you must download the LUT file from:
https://storage.googleapis.com/media.webmproject.org/devsite/vp9/input/hdr/bt2020_to_b...9_example.cube

yes, 3D LUT is one of few ways but as you can read LUT should be source optimized - afraid that there is no universal LUT but it doesn't mean that generalized LUT can't provide acceptable results...

[danfgtn]

I've recently found an interesting suggestion of Google to convert HDR to SDR using a LUT:
https://developers.google.com/media/vp9/hdr-encoding/

Search the page for:
"Converting HDR to SDR"

They do it for VP9, but it also works for AVC/HEVC. To be able to let it run, you must download the LUT file from:
https://storage.googleapis.com/media.webmproject.org/devsite/vp9/input/hdr/bt2020_to_b...9_example.cube

That's interesting, I'm currently testing avs + DGToneMap. It seemed to me that the ffmpeg tonemap works better in certain aspects, but it seems to be much slower than avs +, I'm really in doubt about which one to use and which one really is better.

Which one does the best result these days? But I think it will depend on each source right?

[fornit]

The LUT method doensn't seem to be faster than zscale unfortunately.

From my point of view results look very similar. Here are two examples at 1440p. The Original can be found at: https://hdrsamples.com/exodus-4k-uhd-hdr-sample-footage/

I've used the following commands to create those:

LUT example:

ffmpeg -analyzeduration 10M -probesize 10M -i Exodus_UHD_HDR_Exodus_draft.mp4 -map 0:v:0 -map 0:a:0 -aspect 16:9 -pix_fmt yuv420p -vf scale=2560:1440:in_color_matrix=bt2020,format=rgb48,lut3d=bt2020_to_bt709_example.cube,scale=-1:-1:out_color_matrix=bt709 -c:v libx264 -preset fast -profile:v high -crf 18 -ac 2 -c:a aac -b:a 128k -y exodus-1440p-sdr-lut.mp4

Zscale example:

ffmpeg -analyzeduration 10M -probesize 10M -i Exodus_UHD_HDR_Exodus_draft.mp4 -map 0:v:0 -map 0:a:0 -aspect 16:9 -vf scale=2560:1440,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 libx264 -preset fast -profile:v high -crf 18 -c:a aac -b:a 192k -y exodus-1440p-sdr-zscale.mp4

[danfgtn]

The LUT method doensn't seem to be faster than zscale unfortunately.

From my point of view results look very similar. Here are two examples at 1440p. The Original can be found at: https://hdrsamples.com/exodus-4k-uhd-hdr-sample-footage/

I've used the following commands to create those:

LUT example:

ffmpeg -analyzeduration 10M -probesize 10M -i Exodus_UHD_HDR_Exodus_draft.mp4 -map 0:v:0 -map 0:a:0 -aspect 16:9 -pix_fmt yuv420p -vf scale=2560:1440:in_color_matrix=bt2020,format=rgb48,lut3d=bt2020_to_bt709_example.cube,scale=-1:-1:out_color_matrix=bt709 -c:v libx264 -preset fast -profile:v high -crf 18 -ac 2 -c:a aac -b:a 128k -y exodus-1440p-sdr-lut.mp4

Zscale example:

ffmpeg -analyzeduration 10M -probesize 10M -i Exodus_UHD_HDR_Exodus_draft.mp4 -map 0:v:0 -map 0:a:0 -aspect 16:9 -vf scale=2560:1440,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 libx264 -preset fast -profile:v high -crf 18 -c:a aac -b:a 192k -y exodus-1440p-sdr-zscale.mp4

Zscale with ffmpeg seems the best choice, compared the videos you attached, the LUT was worse with the brightness compared to zscale.
Dgtonemap in avs + failed, doing the test in this video the script became very slow and the output was a green screen, I tried to correct changing the input-depth and output-depth but it did not work. I should not know how to use the filter correctly.