If you use this same exact string with the current version of FFmpeg (I tested version N-93083-g8522d219ce), the encoding time drops from 226,080 seconds (45K times real-time) to 18,196 seconds, or about 3,639 times real-time, a speedup of about 12x. The command string used back in our initial tests was this:įfmpeg -y -i input.mp4 -c:v libaom-av1 -strict -2 -b:v 3000K -maxrate 6000K -cpu-used 8 -pass 1 -f matroska NUL & \įfmpeg -i input.mp4 -c:v libaom-av1 -strict -2 -b:v 3000K -maxrate 6000K -cpu-used 0 -pass 2 output_AV1.mkv If you want to take the time to learn how I got there, let’s break down the components. If you’re in a TL/DR kind of mood, you can jump down to Table 6 and see a comparison that is fair to the other codecs. As you’ll read below, things aren’t exactly apples to apples, and I’m not exactly being fair to the other codecs, but all that notwithstanding it’s a pretty impressive speedup, wouldn’t you agree?
Current optimized encoding times for AV1īased upon the old encoding times from the August 2018 review for the other codecs, AV1 was down to about 3x the encoding times of x265 and LibVPx. Since it takes 6 VMF points to make a Just Noticeable Difference, even the sharpest-eyed viewer wouldn’t notice this. Since I know you’re wondering, the VMAF quality for the clip compressed last year was 96.18 the quality for the clip referenced in Table 2 is 95.55. I just finished that project, and Table 2 shows where things stand now. So, when I started a recent codec evaluation project, I was eager to see if I could match those times.
Starting in late 2018, I wrote that researchers had reported AV1 encoding times as low as 10x LibVPx encoding times. Encoding times for the first release of AV1 In addition, LibVPx is the implementation of VP9 in FFmpeg, and all references to AV1 refer to the AV1 codec available in FFmpeg. Unless otherwise indicated, all encoding times are on my HP ZBook notebook powered by a single 2.8 GHz Intel Xeon E3-1505M v5 CPU.
When I first tested AV1 encoding back in August 2018 encoding times were glacial and seriously detracted from the potential usability of the codec.
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