3 ms·

VP9 being 9x slower than x264 is hard to believe. Do you have a citation?

Sir_Cmpwn 11y ago
I can anecdotally agree with him. I ran a service that did a lot of media encoding and VP9 is very, very slow to encode.
- DarkLinkXXXX 11y ago
  Could that be due to lack of hardware support?
  - TD-Linux 11y ago
    No, generally encoding is done in software. It's just because VP9 is a much more complex format with many more different coding possibilities to search. It also hasn't been around as long as x264 to be hyper-optimized.
  - astrange 11y ago
    There are probably some issues with missing SIMD, but no further hardware support would be helpful. It's purely an implementation issue - you don't get software as good as x264 just by paying for it.
  - mappu 11y ago
    Comparing x264 to hardware-accelerated encoders (QuickSync, NVENC, VCE), the speed/quality/bitrate tradeoff is massively in favour of the cpu-only x264. So i think hardware encoding could help VP9, but it's not a magic bullet (unless your CPU is busy with other work simultaneously).
mappu 11y ago
"VP9 encoding (using libvpx) is horrendously slow – like, 50x slower than VP8/x264 encoding. This means that encoding a 3-minute 1080p clip takes several days on a high-end machine. ... libvpx multithreading [encoding] performance is deplorable. It gains virtually nothing."[1] 1. https://blogs.gnome.org/rbultje/2014/02/22/the-worlds-fastest-vp9-decoder-ffvp9/ https://blogs.gnome.org/rbultje/2014/02/22/the-worlds-fastes... n.b. x264 comparisons were taken with `--preset veryslow` which understates x264's potential performance by an order of magnitude. From the same link: "it can be fast, and it can beat x264, but it can’t do both at the same time."
- TD-Linux 11y ago
  This is old. libvpx 1.4.0 is a lot faster now and has multithreading. On my i7-4900MQ laptop, I get about 3fps encoding 1080p content. Still very slow, but 24 minutes for a 3 minute clip, not days.

I can anecdotally agree with him. I ran a service that did a lot of media encoding and VP9 is very, very slow to encode.

DarkLinkXXXX 11y ago
Could that be due to lack of hardware support?
- TD-Linux 11y ago
  No, generally encoding is done in software. It's just because VP9 is a much more complex format with many more different coding possibilities to search. It also hasn't been around as long as x264 to be hyper-optimized.
- astrange 11y ago
  There are probably some issues with missing SIMD, but no further hardware support would be helpful. It's purely an implementation issue - you don't get software as good as x264 just by paying for it.
- mappu 11y ago
  Comparing x264 to hardware-accelerated encoders (QuickSync, NVENC, VCE), the speed/quality/bitrate tradeoff is massively in favour of the cpu-only x264. So i think hardware encoding could help VP9, but it's not a magic bullet (unless your CPU is busy with other work simultaneously).

mappu 11y ago

"VP9 encoding (using libvpx) is horrendously slow – like, 50x slower than VP8/x264 encoding. This means that encoding a 3-minute 1080p clip takes several days on a high-end machine. ... libvpx multithreading [encoding] performance is deplorable. It gains virtually nothing."[1] 1. https://blogs.gnome.org/rbultje/2014/02/22/the-worlds-fastest-vp9-decoder-ffvp9/ https://blogs.gnome.org/rbultje/2014/02/22/the-worlds-fastes... n.b. x264 comparisons were taken with `--preset veryslow` which understates x264's potential performance by an order of magnitude. From the same link: "it can be fast, and it can beat x264, but it can’t do both at the same time."

TD-Linux 11y ago
This is old. libvpx 1.4.0 is a lot faster now and has multithreading. On my i7-4900MQ laptop, I get about 3fps encoding 1080p content. Still very slow, but 24 minutes for a 3 minute clip, not days.