On 3/8/16, Moritz Barsnick <barsn...@gmx.net> wrote: > Hi Sreenath, > > On Mon, Mar 07, 2016 at 22:28:32 +0530, Sreenath BH wrote: >> As can be seen the two outputs differ in the H264 profile(High vs >> Main), bitrate, the pixel format and of course the file sizes. > > Different encoders can have different defaults. It appears that nvenc > defaults to "Main", while libx264 defaults to preset "medium" which > apparently implies "High" (but might depend on other things). > > 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. > > And finally, don't expect the same results as soon as you have the same > profile, levels and bitrate (or quality). One encoder will be more > efficient than the other, or give different results in different scene > scenarios. > > Does this clarify some things? > > Moritz > _______________________________________________ > ffmpeg-user mailing list > ffmpeg-user@ffmpeg.org > http://ffmpeg.org/mailman/listinfo/ffmpeg-user >
Hi 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. thanks, Sreenath _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user
