3 ms·

30fps on a 9900KS at 1080p. Three to four times slower than x264. As you say, for ahead of time, write once, read many media like Netflix, that's an acceptable

30fps on a 9900KS at 1080p. Three to four times slower than x264. As you say, for ahead of time, write once, read many media like Netflix, that's an acceptable trade. It's not going to work for live media yet. But 10bit 4k streams need nearly 50gb RAM and exponentially more time than 1080p. I've never had much luck.

miohtama 7y ago
Which codec features do make it RAM hungry? Are they optional and can be turned off in the encoder?
- cogman10 7y ago
  Codecs like AV1 do a LOT of motion and transformation detection. That's generally where a lot of that ram goes, They are storing a metric ton of matrix data from prior (and future? I'm not sure if AV1 does this) frames so that when calculating the current frame stream they can quickly look up that info. Needless to say. figuring out which piece of data should be plucked out and transformed from prior frames is really computationally expensive. Here's a paper on exactly what sort of tools are available for the codec. https://jmvalin.ca/papers/AV1_tools.pdf https://jmvalin.ca/papers/AV1_tools.pdf edit I should note that the data stream for H.264 is FAR simpler. It doesn't support nearly the number of transformations that AV1 does.
clouddrover 7y ago
> It's not going to work for live media yet. Cisco's AV1 encoder does 1080p30 encoding for video calls on a laptop. They found it's a matter of tuning the encoder for the live video use case: https://blogs.cisco.com/collaboration/cisco-leap-frogs-h-264-video-collaboration-with-real-time-av1-codec https://blogs.cisco.com/collaboration/cisco-leap-frogs-h-264... Xilinx is working on FPGA based encoding for AV1. They already offer it for VP9 (they bought NGCodec) and Twitch is using it: https://www.xilinx.com/applications/data-center/video-imaging.html https://www.xilinx.com/applications/data-center/video-imagin... https://blog.twitch.tv/en/2018/12/19/how-v-p9-delivers-value-for-twitch-s-esports-live-streaming-35db26f6322f/ https://blog.twitch.tv/en/2018/12/19/how-v-p9-delivers-value...
kabes 7y ago
You can't draw conclusions from this for live streaming. That's typically just a subset of the encoder being used in 1 pass. Same for h264 etc. The live streaming part of av1 is still full on the works. RTP packet formats for SVC isn't even finished yet, let alone implemented in a codec.
- oliwarner 7y ago
  Not drawing conclusions. That's why I said "yet". Spec, hardware encoders and maybe even software encoder improvements will likely make it practical.

miohtama 7y ago

Which codec features do make it RAM hungry? Are they optional and can be turned off in the encoder?

cogman10 7y ago
Codecs like AV1 do a LOT of motion and transformation detection. That's generally where a lot of that ram goes, They are storing a metric ton of matrix data from prior (and future? I'm not sure if AV1 does this) frames so that when calculating the current frame stream they can quickly look up that info. Needless to say. figuring out which piece of data should be plucked out and transformed from prior frames is really computationally expensive. Here's a paper on exactly what sort of tools are available for the codec. https://jmvalin.ca/papers/AV1_tools.pdf https://jmvalin.ca/papers/AV1_tools.pdf edit I should note that the data stream for H.264 is FAR simpler. It doesn't support nearly the number of transformations that AV1 does.

clouddrover 7y ago

> It's not going to work for live media yet. Cisco's AV1 encoder does 1080p30 encoding for video calls on a laptop. They found it's a matter of tuning the encoder for the live video use case: https://blogs.cisco.com/collaboration/cisco-leap-frogs-h-264-video-collaboration-with-real-time-av1-codec https://blogs.cisco.com/collaboration/cisco-leap-frogs-h-264... Xilinx is working on FPGA based encoding for AV1. They already offer it for VP9 (they bought NGCodec) and Twitch is using it: https://www.xilinx.com/applications/data-center/video-imaging.html https://www.xilinx.com/applications/data-center/video-imagin... https://blog.twitch.tv/en/2018/12/19/how-v-p9-delivers-value-for-twitch-s-esports-live-streaming-35db26f6322f/ https://blog.twitch.tv/en/2018/12/19/how-v-p9-delivers-value...

kabes 7y ago

You can't draw conclusions from this for live streaming. That's typically just a subset of the encoder being used in 1 pass. Same for h264 etc. The live streaming part of av1 is still full on the works. RTP packet formats for SVC isn't even finished yet, let alone implemented in a codec.

oliwarner 7y ago
Not drawing conclusions. That's why I said "yet". Spec, hardware encoders and maybe even software encoder improvements will likely make it practical.