[FFmpeg-devel] [PATCH] Change libvpx-vpx default to crf=32.

[Elliott Karpilovsky]

On Wed, Sep 4, 2019 at 9:53 AM James Zern
<jzern-at-google.com at ffmpeg.org> wrote:
>
> Hi,
>
> On Wed, Aug 28, 2019 at 2:26 PM Elliott Karpilovsky
> <elliottk-at-google.com at ffmpeg.org> wrote:
> >
> > Current default is 200kbps, which produces inconsistent
> > results (too high for low-res, too low for hi-res). Use
> > CRF instead, which will adapt. Affects vp8/vp9. Also
> > have VP8 use a default bitrate of 256kbps.
> > ---
> >  libavcodec/libvpxenc.c | 71 +++++++++++++++++++++++++++++++++++-------
> >  libavcodec/version.h   |  2 +-
> >  2 files changed, 61 insertions(+), 12 deletions(-)
> >
>
> Some cosmetics, seems to work as expected with tip of tree and v1.4.0.
>
> > diff --git a/libavcodec/libvpxenc.c b/libavcodec/libvpxenc.c
> > index feb52ea0dd..42504ab95e 100644
> > --- a/libavcodec/libvpxenc.c
> > +++ b/libavcodec/libvpxenc.c
> > @@ -510,6 +510,63 @@ static void set_color_range(AVCodecContext *avctx)
> >  #endif
> >  #endif
> >
> > +/**
> > + * Set the target bitrate to VPX library default. Also set CRF to 32 if needed.
> > + */
> > +static void set_vp8_defaults(AVCodecContext *avctx,
> > +                             struct vpx_codec_enc_cfg *enccfg) {
>
> Indent should be 4 and the brace for a function on a new line [1].
>

Will send a patch with this fixed.

> > [...]
> > +
> > +/**
> > + * Called when the bitrate is not set. It sets appropriate default values for
> > + * bit-rate and CRF.
>
> 'bitrate' is more common in this file.
>

Ditto.

> > [...]
> > diff --git a/libavcodec/version.h b/libavcodec/version.h
> > index e70ebc0c70..cda6dbae47 100644
> > --- a/libavcodec/version.h
> > +++ b/libavcodec/version.h
> > @@ -29,7 +29,7 @@
> >
> >  #define LIBAVCODEC_VERSION_MAJOR  58
> >  #define LIBAVCODEC_VERSION_MINOR  55
> > -#define LIBAVCODEC_VERSION_MICRO 101
> > +#define LIBAVCODEC_VERSION_MICRO 102
> >
>
> This no longer applies cleanly.
>

Ditto.

> [1] http://ffmpeg.org/developer.html#Code-formatting-conventions

Thank you for the link. I've updated my editor based on the
recommendations there.