[FFmpeg-devel] [PATCH] Remove qmin and qmax constraints for nvenc vbr

Ganapathy Raman Kasi gkasi at nvidia.com
Fri Feb 24 04:01:07 EET 2017


Adding on to the previous mail,
To test this patch, please try :

i) ffmpeg -y -i $INPUT -vcodec h264_nvenc -preset medium $OUT_medium.mp4
ii) ffmpeg -y -i $INPUT -vcodec h264_nvenc -preset medium $OUT_slow.mp4

Without patch : $OUT_medium and $OUT_slow will be binary identical since both use NV_ENC_PARAMS_RC_VBR
With patch : $OUT_medium and $OUT_slow will be different and ii) will take more time to run and usually results in better quality. Thanks

Ganapathy


-----Original Message-----
From: ffmpeg-devel [mailto:ffmpeg-devel-bounces at ffmpeg.org] On Behalf Of Ganapathy Raman Kasi
Sent: Thursday, February 23, 2017 5:42 PM
To: FFmpeg development discussions and patches <ffmpeg-devel at ffmpeg.org>
Subject: [FFmpeg-devel] [PATCH] Remove qmin and qmax constraints for nvenc vbr

Hi,


qmin and qmax are not necessary for nvenc vbr. Enforcing this constraint, doesn't allow user to use vbr 2 pass mode (

NV_ENC_PARAMS_RC_2_PASS_VBR) without explicity setting the qmin and qmax options and reverts to the default vbr mode (

NV_ENC_PARAMS_RC_VBR). If needed user can still set qmin and qmax and those will be obeyed. Please review. Thanks.


Regards

Ganapathy Kasi

-----------------------------------------------------------------------------------
This email message is for the sole use of the intended recipient(s) and may contain confidential information.  Any unauthorized review, use, disclosure or distribution is prohibited.  If you are not the intended recipient, please contact the sender by reply email and destroy all copies of the original message.
-----------------------------------------------------------------------------------


More information about the ffmpeg-devel mailing list