Log in

View Full Version : X264/5 compression efficiency ultrafast vs placebo?


YaBoyShredderson
25th July 2020, 07:43
Has anyone done any in depth tests about x264 and x265 as it relates to the presets? General rule of thumb is to use the slowest you can stand to wait, but ignore placebo as its too slow for the gain (and can create compatabilty issues).

With handbrake x264 i use veryslow, one notch above placebo, and i dont mind waiting for it if its better. I havent done anything with x265, but im going to start encoding my 4k blurays with staxrip, and wanted to know whats a good preset to use with x265, i was planning on using slow.

jlw_4049
25th July 2020, 07:57
Has anyone done any in depth tests about x264 and x265 as it relates to the presets? General rule of thumb is to use the slowest you can stand to wait, but ignore placebo as its too slow for the gain (and can create compatabilty issues).



With handbrake x264 i use veryslow, one notch above placebo, and i dont mind waiting for it if its better. I havent done anything with x265, but im going to start encoding my 4k blurays with staxrip, and wanted to know whats a good preset to use with x265, i was planning on using slow.I recommend slow for 4k, best trade off for quality and speed.

Even then on a 3900x you're gonna be looking at like 16 hours for an encoce.

Sent from my SM-G986U1 using Tapatalk

YaBoyShredderson
25th July 2020, 17:29
Cool, ill use slow. Also whats the difference in efficiency and speed with main vs high? Both x264 and x265 if you know. Thanks.

jlw_4049
25th July 2020, 17:32
Cool, ill use slow. Also whats the difference in efficiency and speed with main vs high? Both x264 and x265 if you know. Thanks.As far as i know they enable different features. I dont know all the technical differences off hand something I always have to read.

But for x264 you should always use high now a days.

Sent from my SM-G986U1 using Tapatalk

mastrboy
1st August 2020, 21:29
x264 and x265 has different approaches to the presets the last time I tested.

With X264 the slower the preset, the smaller the filesize, but with x265 it's been the opposite in my tests.
Due to this I found that just going with medium/slow for x265 and lowering the CRF instead produce just as good results quality wise as a slower preset and takes less encode time.

jlw_4049
2nd August 2020, 01:49
Very slow for x264 and slow for x265

Sent from my SM-G986U1 using Tapatalk