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Old 4th October 2019, 18:28   #63  |  Link
benwaggoner
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Join Date: Jan 2006
Location: Portland, OR
Posts: 4,750
Quote:
Originally Posted by Boulder View Post
Do you think that just setting --ssim would be enough or is tuning needed? I did two quick tests, and at 720p (downscaled from 1080p) --no-hme with --merange 58 was better and at 1080p --hme with --merange 26 was better what comes to SSIM. I did those without changing any other parameters so the psy tunings were there.
After some rumination, I'm not sure that HME doesn't have psychovisual impact after all. I think there could be cases where it could improve handling of random noise that would have gotten low-pass filtered at the lower resolutions, allowing the encoder to spend more bits on signal than noise.

PSNR would be terrible for measuring this. Not sure about SSIM. Looking at divergence between PSNR and SSIM, or PSNR and VMAF, perhaps could be helpful?
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