[FFmpeg-devel] [PATCH v2] avcodec/v210enc: add yuv420p/yuv420p10 input pixel format support

[Limin Wang]

On Sat, Sep 21, 2019 at 03:13:46PM +0200, Carl Eugen Hoyos wrote:
> Am Sa., 21. Sept. 2019 um 14:42 Uhr schrieb <lance.lmwang at gmail.com>:
> >
> > From: Limin Wang <lance.lmwang at gmail.com>
> >
> > With the patch, we simply reuse the same source chroma line for each pair
> > of lines in the output
> 
> Is there really no quality hit for a 20% speed-up?

The quality is OK by my testing for the 420 to 422, I have no idea how
to compare with the difference between them, Micheal can give more suggestion on
that.

however the patch try to fix the autoscale, if user prefer to use
swscale conversion, he can use it still by claims pix_fmt clearly.

The following command shows how to use the old conversion by swscale.
no swscale:
./ffmpeg -y -lavfi testsrc2=s=4096x3072:r=10:d=10,format=pix_fmts=yuv420p -c:v v210 -f null -

swscale:
./ffmpeg -y -lavfi testsrc2=s=4096x3072:r=10:d=10,format=pix_fmts=yuv420p -c:v v210 -pix_fmt yuv422p -f null -


Thanks,
Limin
> 
> Carl Eugen
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
> 
> To unsubscribe, visit link above, or email
> ffmpeg-devel-request at ffmpeg.org with subject "unsubscribe".