[FFmpeg-user] Specifying lib path when building ffmpeg

[Carl Eugen Hoyos]

2016-11-04 19:18 GMT+01:00 Matteo Naccari <Matteo.Naccari at bbc.co.uk>:

>> Could you comment on the performance of libturing wrt libvpx and the
>> quality compared to FFmpeg's asp encoder?
>
> We haven't compared with libvpx as the Turing codec is compliant with
> HEVC . Usually we compare with the reference implementation to
> appreciate how the algorithmic work gets the codec close to the reference.

(I am assuming here that libturing is both slower and produces worse
quality than libx265, if this is not true, the following has of course little
relevance.)

I don't think comparing to a reference implementation makes sense if
better implementations exist and are used.
If libturing has abysmal quality at a useless speed, the wrapper will not
be accepted in FFmpeg and you don't have to send a patch. Since the
license of libturing is more liberal than the license of libx265, you don't
have to beat its quality. And since libvpx (a codec with an even more
liberal license) has a mostly absurd performance, you may not even
have to beat its quality, it should be enough to beat its speed.
If your encoder does not beat our mpeg4 encoder quality-wise, it
probably should not be used.

None of these tests have to be scientific: If libturing doesn't beat
FFmpeg asp by a clear psnr-margin, you have real issues and the
performance test to compare with libvpx is easy to do.

Iirc, there is at least one more hevc encoder under lgpl, you may
want to compare with that one as well.

> This e-mail (and any attachments) is confidential

Please avoid this when sending emails to a public mailing list: Imo,
it makes your company look stupid.

Carl Eugen