3 ms·

"compared to x264 high profile at roughly the same quality" Compared how? With what kind of source videos? Unless you are matching SSIM on similar content I d

by tveita 9y ago

"compared to x264 high profile at roughly the same quality" Compared how? With what kind of source videos? Unless you are matching SSIM on similar content I don't think you can meaningfully compare your numbers to the ones in the article.

keldaris 9y ago
It's certainly not a precise comparison, you're right. Nevertheless, compare for instance x264 and x265. Exactly how large the difference between the two is depends on the type of content, bitrate, resolution and other factors, but it's hard to find any case (encoding speeds aside) where x265 wouldn't be substantially better, to the point where we generally call H.265 a better codec. I was expecting a similar kind of leap with AV1. This comparison may not be conclusive, but it looks like that's probably not going to happen.
NelsonMinar 9y ago
Me, I just take x264 video I downloaded off the back of a truck and re-encode it to x265 with default settings on FFmpeg. It looks the same visually to me on my TV but the file size (including audio) is typically 25%. I realize this is the opposite of a carefully controlled codec experiment. Just saying in practice it works pretty well. If you're curious about x265 in practice, the pirate scene group PSA-Rips is doing a good job recoding stuff to x265. http://psarips.com/ http://psarips.com/
- marcusjt 9y ago
  To be a little fairer you should transcode it to both x264 and x265 so that the outputs are can be compared to each other (rather than comparing the transcoded x265 to the source x264 as you did, which isn't quite the same thing).
  - NelsonMinar 9y ago
    I did that experiment with a file I found online. The source x264 video stream was 1600 MB. My x264 recoding was 290 MB, and the x265 was 80 MB. (There's also a significant savings in ffmpeg recoding the audio, which accounts for the file sizes I reported). In all cases I'm sure my result is lower quality, but still more than acceptable for me watching TV with low expectations.

by tveita 9y ago

keldaris 9y ago

It's certainly not a precise comparison, you're right. Nevertheless, compare for instance x264 and x265. Exactly how large the difference between the two is depends on the type of content, bitrate, resolution and other factors, but it's hard to find any case (encoding speeds aside) where x265 wouldn't be substantially better, to the point where we generally call H.265 a better codec. I was expecting a similar kind of leap with AV1. This comparison may not be conclusive, but it looks like that's probably not going to happen.

NelsonMinar 9y ago

Me, I just take x264 video I downloaded off the back of a truck and re-encode it to x265 with default settings on FFmpeg. It looks the same visually to me on my TV but the file size (including audio) is typically 25%. I realize this is the opposite of a carefully controlled codec experiment. Just saying in practice it works pretty well. If you're curious about x265 in practice, the pirate scene group PSA-Rips is doing a good job recoding stuff to x265. http://psarips.com/ http://psarips.com/

marcusjt 9y ago
To be a little fairer you should transcode it to both x264 and x265 so that the outputs are can be compared to each other (rather than comparing the transcoded x265 to the source x264 as you did, which isn't quite the same thing).
- NelsonMinar 9y ago
  I did that experiment with a file I found online. The source x264 video stream was 1600 MB. My x264 recoding was 290 MB, and the x265 was 80 MB. (There's also a significant savings in ffmpeg recoding the audio, which accounts for the file sizes I reported). In all cases I'm sure my result is lower quality, but still more than acceptable for me watching TV with low expectations.