For those of you that torrent video files this question is geared toward you. I’m looking for a sweet spot between quality, size & speed for HEVC encoding. I’m using FastFlix and seem to be getting really wide and varying speeds.
I’m not really literate on all this video lingo but I can, at least, get it going. Most files take anywhere from 5-17 mins for a 30-40 mins clip. I have a AMD Radeon RX 470 graphics card but when I try and use the VCEEnc it won’t let me use CRF which I’ve heard it the best way.
Anyway, if you’re willing to share knowledge or what settings you use when you convert video to HEVC that might help me speed up my processing, I would be eternally grateful.
You need to do 2 pass encoding. You should also not use CRF. You should pick a bitrate for the file size you want. Do a first pass which analyzes the video to see which sections require more data, and then run a second pass which will give high bitrate to more action scenes and lower bitrate to the credits and slower talking scenes.
Some action scenes require 5 times more data to look as good as a talking dinner scene, you couldn’t even notice the quality difference but the bitrate requirement is literally 5 times more.
You also need to use the slow preset and use x265 if you’re doing this to archive the stuff forever. Do it once and do it right.
Thank you, this is VERY helpfuly information! As I mentioned in another reply the ffmpeg front-end I use FastFlix only allows bitrate or CQ encoding when using the VCEEnc Hardware encoder for AMD so your information is noted and very appreciated!
2 pass encoding is only to get the benefits of variable bit rate when targeting a specific file size. If you don’t have a specific file size in mind, that’s what CRF is for.
No, the specific file size is irrelevant, he’s wanting smaller file sizes. CRF is a waste of data on more than 70% of scenes in hollywood movies. You set a bitrate and let it go. This is also why virtually all music now is VBR
Are you confusing CRF with CBR?
CRF is the video equivalent of VBR music. The music equivalent of two-pass video encoding is ABR music.
When tuned for a specific file, CRF and two-pass video will give similar results. They both result in a variable bitrate encoding.
When using the same config on different files, you might find that two-pass encoding produces unnecessarily large files for something with little movement like anime, or has quality issues for something with a lot of movement like a lot of shaky camera or film grain. Meanwhile the same CRF setting will work well in just about any scenario, using more bitrate for files that need it, and less bitrate for files that don’t.