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Yes, I have spent hundreds of hours in comparing video encoder results, but that's beside the point. One don't need to have done that to be able to tell your ex

Yes, I have spent hundreds of hours in comparing video encoder results, but that's beside the point. One don't need to have done that to be able to tell your experiment is flawed. All you have is literally one datapoint, 970kbps h264 has "no visible difference" compared with 800kbps h265, and I believe that. But maybe 800kbps h264 also doesn't have visible difference from it. Maybe there is just not much difference to notice from 500 to 1200kbps, for your specific video. Again, my point is your experiment has too few samples (literally 1 pair). Using that to conclude anything is the exact opposite of "scientific" method. I never say "h265 isn't better than h264" or "your result is wrong"; just your result doesn't prove the former. If you insist to use just one sample, you could at least use the same bitrate (2-pass if you want to have better rate control) and say "hey, the h265 one is visibly better!", and that would be more convincing.

boomboomsubban 5y ago
>Again, my point is your experiment has too few samples (literally 1 pair). This experiment was to show that the gains the original post made wasn't solely due to the video being an unchanging desktop. There were enough samples done to show that claim seems to be false, though more data could change that. Basically, you're misunderstanding the theory tested, and while your complaints would make sense testing a different theory, they don't discount the experimental evidence for the tested theory.
- fireattack 5y ago
  > was to show that the gains the original post made wasn't solely due to the video being an unchanging desktop I assume your point is "while both reduced the size (from an unchanging desktop, which is easily compressible), H.265 reduces the size even further. So it (the choice of codec) is also a contributing factor." And I get it. My point is that even this wasn't proved by his experiment, because he failed to prove the two outputs have the same quality. And without having this, comparing file size is meaningless (because as stated by others, with lossy codec you can generate arbitrary file size by tweaking the parameters). Yes, he did say "there is no visible difference". However, most of people can't tell any difference bwtween 600kbps and 1000kbps, using the same codec, either. In other words, there is a huge range of bitrates where average eyes can't tell difference. So the "same quality" premise has to be very strict and objective. It's not I'm trying to be picky. A better approach, as I have said above, is to fix bitrate instead of quality. This way, you can find a certain point where people DO find the difference in quality, and then you can conclude more confidently that one is better than the other due to higher quality/filesize ratio.
  - boomboomsubban 5y ago
    >My point is that even this wasn't proved by his experiment, because he failed to prove the two outputs have the same quality. If the gains were purely due to an unchanging image, both conversions should have chopped the file size to basically nothing. Any file size difference due to quality would be dwarfed by reduction due to compression of like 600 images down to a handful.
    - fireattack 5y ago
      My original comment is about his experiment can't prove H.265 is better than H.264 (and I think that's what he wanted to show). Of course modern video codecs can compress video very well regardless if the input is "unchanged image" or not. I was not arguing about this.
      - boomboomsubban 5y ago
        >and I think that's what he wanted to show). It wasn't. The test was whether reencoding was what's important, or the codec used. I'm the one that asked the question Dylan was kind enough to try and answer, your further testing would not answer my question any better.
        fireattack 5y ago
        He was replying to stevenhuang, not you directly. stevenhuang said "Reencoding the same input file as h264 again but using FFmpeg defaults would probably yield similar file size reductions." So, it looks to me he was trying to refute that "using H264 again would yield similar file size reduction". If you think it's not, that's fine. Not something worth debating.

boomboomsubban 5y ago

>Again, my point is your experiment has too few samples (literally 1 pair). This experiment was to show that the gains the original post made wasn't solely due to the video being an unchanging desktop. There were enough samples done to show that claim seems to be false, though more data could change that. Basically, you're misunderstanding the theory tested, and while your complaints would make sense testing a different theory, they don't discount the experimental evidence for the tested theory.

fireattack 5y ago
> was to show that the gains the original post made wasn't solely due to the video being an unchanging desktop I assume your point is "while both reduced the size (from an unchanging desktop, which is easily compressible), H.265 reduces the size even further. So it (the choice of codec) is also a contributing factor." And I get it. My point is that even this wasn't proved by his experiment, because he failed to prove the two outputs have the same quality. And without having this, comparing file size is meaningless (because as stated by others, with lossy codec you can generate arbitrary file size by tweaking the parameters). Yes, he did say "there is no visible difference". However, most of people can't tell any difference bwtween 600kbps and 1000kbps, using the same codec, either. In other words, there is a huge range of bitrates where average eyes can't tell difference. So the "same quality" premise has to be very strict and objective. It's not I'm trying to be picky. A better approach, as I have said above, is to fix bitrate instead of quality. This way, you can find a certain point where people DO find the difference in quality, and then you can conclude more confidently that one is better than the other due to higher quality/filesize ratio.
- boomboomsubban 5y ago
  >My point is that even this wasn't proved by his experiment, because he failed to prove the two outputs have the same quality. If the gains were purely due to an unchanging image, both conversions should have chopped the file size to basically nothing. Any file size difference due to quality would be dwarfed by reduction due to compression of like 600 images down to a handful.
  - fireattack 5y ago
    My original comment is about his experiment can't prove H.265 is better than H.264 (and I think that's what he wanted to show). Of course modern video codecs can compress video very well regardless if the input is "unchanged image" or not. I was not arguing about this.
    - boomboomsubban 5y ago
      >and I think that's what he wanted to show). It wasn't. The test was whether reencoding was what's important, or the codec used. I'm the one that asked the question Dylan was kind enough to try and answer, your further testing would not answer my question any better.
      - fireattack 5y ago
        He was replying to stevenhuang, not you directly. stevenhuang said "Reencoding the same input file as h264 again but using FFmpeg defaults would probably yield similar file size reductions." So, it looks to me he was trying to refute that "using H264 again would yield similar file size reduction". If you think it's not, that's fine. Not something worth debating.