[FFmpeg-devel] [PATCH] nvenc:Add Fractional CQ Support

Timo Rothenpieler timo at rothenpieler.org
Wed May 10 12:41:57 EEST 2017

Am 10.05.2017 um 10:38 schrieb Hendrik Leppkes:
> On Wed, May 10, 2017 at 10:31 AM, Timo Rothenpieler
> <timo at rothenpieler.org> wrote:
>> Am 10.05.2017 um 08:49 schrieb Yogender Gupta:
>>> CQ rate control in NVENC now supports fractional values (SDK 8.0). Please
>>> find patch attached for the same.
>>> Thanks,
>>> Yogender
>> applied, thanks!
>> I'm wondering what the difference between this and constqp mode is, does
>> this set a constant quality in otherwise vbr mode?
> Sounds to me like this doesn't change or introduce a new RC mode, just
> allows the existing CQ modes to use fractional values, ie. more
> precision?

Yes, this patch only enhances that parameter. Was more meant in general,
as I never fully understood what that parameter does.

The constqp rc mode uses the -qp parameter to set its constant quality.
This is something different, and from my observation is fully
independent, at least I see no difference when setting this parameter in
constqp mode.

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