rbjtech 527 Posted February 19 Share Posted February 19 (edited) So a question for @softworkz most likely. I've been playing around with ffmpeg with the TM filters trying to get Tone Mapped chapter thumbnails created in the .bif's. I can't seem to use the TM filter in the image extractor in ffmpeg - ffmpeg is reporting that this function cannot use the filter. I have got it 'working' if I simply do a TM conversion to a thumbnail resolution video (to rapidly increase it's conversion speed) and then re-run the thumbnail extract on that to produce the 'SDR/tone mapped' images. Then delete the TM video file. I was hoping to do it all in a single ffmpeg command. It's obviously not urgent - but the 'washed out' thumbnail images on an SDR display are nagging me .. Any thoughts ? Edited February 19 by rbjtech 4 Link to post Share on other sites
rbjtech 527 Posted Sunday at 02:45 PM Author Share Posted Sunday at 02:45 PM So @cayars reminded me that you can just use filter with tone mapping on the existing ffmpeg command line - but this is CPU only - ffmpeg.exe -f matroska -skip_interval 30 -copyts -i file:"input.mkv" -vf "zscale=transfer=linear,tonemap=mobius,zscale=transfer=bt709" -an -sn -s 320x180 -vsync cfr -r 0.1 -f image2 "C:\temp\img_%05d.jpg" For the time being, I may just script rebuilding my 4K library with these newly generated bif's using biftool to create them. Down the line, I guess it would be nice for the image extractor to look at the colour space and apply the filter as necessary - I don't believe it uses h/w acceleration today ? So this is probably not a big deal to just include the optional TM filter. 2 Link to post Share on other sites
cayars 1890 Posted Sunday at 04:59 PM Share Posted Sunday at 04:59 PM Hey I hope it takes you a long, long time to create the bif files. You have lots of 4K media then. I don't think this will be as bad as you think, fingers crossed. Link to post Share on other sites
rbjtech 527 Posted Tuesday at 11:07 AM Author Share Posted Tuesday at 11:07 AM (edited) So @softworkz has been busy in the background .. Looking at the ffmpeg command line in the logs, it appears the new beta is applying a gamma/saturation filter to attempt to correct the SDR/HDR issues. My thoughts are it certainly looks better than no TM, but it's possibly too dark imo. I've put the 3 methods below - top row is no TM, middle row is using TM/Mobius, bottom row is gamma/sat filter, Personally, I think the middle row looks the best by far. I'll do some more research on this to look the cpu load of a gamma/sat filter vs doing a proper (cpu) TM - as from my initial look, there wasn't much difference. Edited Tuesday at 11:08 AM by rbjtech Link to post Share on other sites
softworkz 796 Posted Wednesday at 09:18 PM Share Posted Wednesday at 09:18 PM Check out the next version, should be a bit brighter. Also check with multiple different videos. The current is a quick and lightweight solution. It has taken great effort to achieve the quick image extraction that we have and I don't want to unnecessarily load it with something that adds again. We'll see how it works out and revisit this subject if it doesn't. BTW: HW acceleration for image extraction is totally pointless (for our quick-image-extraction at least). I've explained the background somewhere here in the forums. Link to post Share on other sites
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