[FFmpeg-devel] [PATCH 2/2] add libyami.cpp for h264 decoding by libyami

[Ronald S. Bultje]

Hi,

On Mon, Jan 12, 2015 at 9:04 AM, wm4 <nfxjfg at googlemail.com> wrote:

> On Mon, 12 Jan 2015 08:24:35 -0500
> "Ronald S. Bultje" <rsbultje at gmail.com> wrote:
>
> > Hi,
> >
> > On Mon, Jan 12, 2015 at 12:59 AM, Zhao, Halley <halley.zhao at intel.com>
> > wrote:
> >
> > > I understand you concern.
> > > The wrapper doesn't help much to ffmpeg itself, however, it benefits
> much
> > > to the apps uses ffmpeg, to pick up hw capability for codec.
> >
> >
> > So specifically, what are the features that you get with yaml that ffmpeg
> > doesn't already provide (that is: yaml is itself just a wrapper for other
> > stuff; what does it wrap that ffmpeg doesn't have already?). I see
> > h264enc/vp8dec/vp8enc/vp9dec/jpegdec/jpegenc vaapi. Anything else? Why
> not
> > just implement these in ffmpeg directly?
>
> From what I can see:
>
> - libyami doesn't require the relatively terrible boilerplate for
>   hwaccel (creating the hw decoder yourself, maintaining a surface
>   pool, etc.), making this lib very attractive for those who want
>   something simple, and who possibly don't even want to depend on ffmpeg
> - uses some new APIs (not supported by all drivers yet), which work
>   around vaapi suckage, such as requiring a shared context. Namely, the
>   dma_buf stuff.
>
> I wonder how well the latter actually works...


So I don't know if anyone remembers me ranting about libxyz suckage, but
yami sounds a lot like xyz. So: what are the chances that five years down
the line, this lib ends up being unmaintained, having security issues,
portability issues etc., and us basically just being stuck with yet another
xyz that doesn't really solve our issue so we have to re-do it internally
anyway a few years down the line, wishing we had done so a few years
earlier?

There's examples of good xyzs, e.g. x264 is a most wonderful software
project; there's also examples of (imo) fails, such as librtmp. What
guarantees do we have that yami is a good xyz?

Ronald