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  • Format questions: h.264 vs. h.265, and what is SLR Mastering?

I have a couple of questions about format.

  1. Is h.265 better quality than h.264? I downloaded lots of h.264 videos for my old setup which did not play h.265, but now I have Oculus Go, I wondered if it's worth going back and getting the h.265 versions?

  2. What exactly is SLR Mastering? I.e. what treatments are done to the video/sound?

Thanks! 🙂

    BobbyBadass
    1. It depends, if resolution is same then there should be no quality difference visually, but h265 is a more compact codec, that's why files are usually lighter.
    2. SLR Mastering includes stereo alignment, focal plane alignment and color correction if needed. As per sound maybe minor noise filters and other enhancements.

    Welcome!

        Philip 1. It depends, if resolution is same then there should be no quality difference visually, but h265 is a more compact codec, that's why files are usually lighter.

        What I have noticed actually is that the h.265 file is usually slightly bigger than the h.264, e.g. https://www.sexlikereal.com/scenes/three-cheers-for-threesomes-13355

        I knew h.265 was slightly more compact. Yet we see bigger h.265 files. This made me think you may have packed in some extra bit-rate into the h.265 to take advantage of the better compression ratio?

        Do you know what? I'll just download both and post the results of my own comparison here.

          I was right. h.265 has a little more video bit rate packed into it!

          "Three Cheers for Threesomes"
          h.264 bit rate: 9 685 kb/s
          h.265 bit rate: 10.0 Mb/s

          The more you know. 😉

            BobbyBadass It's changed a bit a while ago, before most H265 files were actually smaller because I think it was set up to go for same quality level as H264. H265 needs less space to get the same quality, so when you use H265 at the same quality level as the H264 version that means the file size ends up smaller. Which is great of course.

            But I think the problem is many people don't know about codecs that much and end up using whatever file is bigger, assuming that would be the best version. So I suspect they changed it to aim for similar file sizes regardless of codec to prevent the confusion. The result is that when H264 and H265 versions are about the same file size (assuming all else is the same like resolution etc), then the H265 will always be of higher quality. Unfortunately it's somewhat unnecessary and you lose the advantage of smaller file sizes... But ah well, at least the quality/bitrate is definitely good.

                a year later

                some max quality files are insanely big to download and view offline. If we can take advantage of the H265 codec that would be better. Since the same resolution and same bit rate with H265 vs H264 will not show any obvious quality difference to human eyes, there is no point to have the H265 and H264 the same file size. I think it will be better to remaster the H265 file to a lower bitrate video, maybe about 2025% lower than the original bite rate would still preserve a very good quality video and a much lower file size.

                BobbyBadass It's actually more than just a bit more bitrate.

                Depending on the colors, scene complexity and some other stuff, 10Mbps in h265 pack the same as 20Mbps to 40Mbps in h264

                h264 @1Mbps - h265 @Mbps side-by-side.
                When you pause the video you'll see the differences much clearer.
                Mind it's only 1Mbps so they'll both look terrible nonetheless.
                https://www.youtube.com/watch?v=AekAujM6ZcQ

                a h264 VR scene at 30Mbps
                and a h265 scene at 30Mbps
                Will have roughly the same filesize
                But one will be much higher quality.

                Or
                a h264 at 30Mbps
                and a h265 at 10Mbps
                Will be about the same quality,
                but one will be much smaller.