MeGUI Blu-ray CRF profile

[Nullity]

Disclaimer: I'm a novice when it comes to x264 settings...

The current Blu-ray profiles (including the new ones (http://forum.doom9.org/showthread.php?t=139765)) use a 2-pass bitrate method for encoding:

program --pass 2 --bitrate 8000 --stats ".stats" --level 4.1 --keyint 24 --min-keyint 2 --ref 3 --mixed-refs
--bframes 3 --b-rdo --bime --weightb --direct auto --filter -1,-1 --subme 6 --partitions p8x8,b8x8,i4x4,i8x8
--8x8dct --ipratio 1.1 --pbratio 1.1 --vbv-bufsize 30000 --vbv-maxrate 40000 --qcomp 0.5 --me umh --threads auto
--thread-input --progress --no-psnr --no-ssim --output "output" "input" --mvrange 511 --aud --nal-hrd --sar 1:1

I wanted to do some comparison testing using CRF settings, but still being Blu-ray compatible. What encoding options would I need to change in the above Blu-ray profile to change it from 2-pass to CRF?

If I had to guess, I would say replace --pass 2 --bitrate 8000 --stats ".stats" with --crf 18

Is that all or is it more complicated than that?


EDIT: Also, does anyone know if the new DXVA-HD-HQ profile is Blu-ray standalone compatible, or vice-versa?

[nurbs]

1) You wouldn't have to change any of the other options, but when you use CRF it is harder for x264 to stick to the VBV constraints. So in the end you may end up with a file that the player has trouble playing or may not play at all. Dark Shikari mentioned that quality problems may also arise with this method.

2)The Blu-Ray profile is DXVA compatible.

[Coolpplse]

1) You wouldn't have to change any of the other options, but when you use CRF it is harder for x264 to stick to the VBV constraints. So in the end you may end up with a file that the player has trouble playing or may not play at all. Dark Shikari mentioned that quality problems may also arise with this method.

2)The Blu-Ray profile is DXVA compatible.

As long as the chosen CRF does not allow the final encoded file to peak past the Max VBV value it should be fine though right?

[Dark Shikari]

As long as the chosen CRF does not allow the final encoded file to peak past the Max VBV value it should be fine though right?But you won't know that until afterwards, and during encoding x264 tries to avoid violating VBV constraints--this avoidance process is considerably higher quality in 2pass mode.

[Coolpplse]

But you won't know that until afterwards, and during encoding x264 tries to avoid violating VBV constraints--this avoidance process is considerably higher quality in 2pass mode.

Wait so I use crf 23 for my HD 1080i caps, and right now bitrates have went from 4mbps at the minimum (9-12mbps Average) all the way up to 16mbps max (20mbps spikes very rarely), nothing wrong could possibly occur if I were to reauthor these encodes for a Blu-Ray Standalone in the future could they?

and when you mean how x264 tries to avoid going past the set VBV settings, would x264 still try to maintain the CRF setting I use, at a cost of a higher bitrate?

[Dark Shikari]

Wait so I use crf 23 for my HD 1080i caps, and right now bitrates have went from 4mbps all the way up to 16mbps (20mbps spikes very rarely), nothing wrong could possibly occur if I were to reauthor these encodes to a future blu-ray compatible standard could they?Yes, they'll be fine; as long as they obey the maxrate restriction over the proper buffer size, you won't have any issues.