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View Full Version : x265 preset changes 2.7 ---> 3.0


IgorQ9
21st April 2019, 15:43
Hi, I used to encode my DVDs using QTGMC, x265 v2.7 and preset "veryslow". I recently upgraded to 3.0, but I'm noticing differences i'm not sure im happy with.

FFmpeg 4.1 (using version 2.7 x265)
Test_clip.mp4: Size 11,6mb (veryslow crf 19)

FFmpeg 4.1.1 (using version 3.0 x265)
Test_clip.mp4: Size 12,8mb, Encode speed vs old version: >100% faster (medium, crf=19)
Test_clip.mp4: Size 13,5mb, Encode speed vs old version: >100% faster (slow, crf=19)
Test_clip.mp4: Size 13,8mb, Encode speed vs old version: 5% slower (slower, crf=19)
Test_clip.mp4: Size 13,7mb, Encode speed vs old version: >100% slower (veryslow, crf=19)

I am aware that this comparison is not equal and the new version is probably superior, despite the numbers showing otherwise. I liked using the old version "veryslow" because it was just about as slow as QTGMC, so they lined up nicely. With the new version whatever preset I choose, I will end up with a file atleast 10% larger. Lets say I decide to use "slower" and crf=19.5 that should get me closer to the size of the 2.7 encode. Did anyone test if it has equal or superior quality? Does anyone know exactly what changed so I can test out feeding the settings in manualy to see the results with the new version?

Im also tampering with encoder settings for x265 like no-sao=1, no-strong-intra-smoothing=1 and aq-mode=3. There is a lot of hate on sao on different encoding threads, but most of it seems to be dated. Did you guys test this?

Thanks

Blue_MiSfit
21st April 2019, 22:01
SAO is awesome at most typical bitrates. If you're going for total transparency you'll still probably want to disable it.

IgorQ9
23rd April 2019, 17:43
Thanks guys. After examining what HolyWu posted and reading the the blog post under I'm more comfortable using the new version.

http://x265.org/revamped-veryslow-slower-presets-x265-ver-3-0/