[FFmpeg-user] size and bitrate issues with nvidia accelerated transcoding

[Andy Furniss]

Sreenath BH wrote:
> On 3/8/16, Moritz Barsnick <barsnick at gmx.net> wrote:

>> If you want the same profiles and levels, you will need to request them
>> explicitly.
>>
>> The same thing goes for the quality: libx264 defaults to crf=23, I
>> don't know about nvenc. Furthermore, encoders can trade off quality (or
>> size) for conversion speed. So if you want the same size, you have to
>> specify "-b:v" explicitly. If you want the same quality, I guess you
>> may have to experiment with the settings available to find something
>> comparable.

> Thanks for your comments. I understand that two codecs even with same
> presets and other similar settings can produce differing output.
>
> I wanted to know if there was a way to achieve the results I wanted
> with the codec we prefer to use (nvidia) because it have significant
> speed increase.

Did you try what Moritz wrote above?

Also see nvenc section of

https://trac.ffmpeg.org/wiki/HWAccelIntro