[FFmpeg-devel] [PATCH] avcodec/ffv1enc: choose 1.2 by default for higher resolutions to ensure multi-threaded decodability

[Michael Niedermayer]

On Mon, Dec 09, 2013 at 10:55:53AM +0100, Peter B. wrote:
> Quoting Michael Niedermayer <michaelni at gmx.at>:
> 
> >On Mon, Dec 09, 2013 at 12:46:37AM +0100, Peter B. wrote:
> >>On 12/08/2013 06:25 PM, Michael Niedermayer wrote:
> >>> Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
> >>> ---
> >>>  libavcodec/ffv1enc.c |    4 ++++
> >>>  1 file changed, 4 insertions(+)
> >>>
> >>> diff --git a/libavcodec/ffv1enc.c b/libavcodec/ffv1enc.c
> >>> index 2c87d7a..4856be5 100644
> >>> --- a/libavcodec/ffv1enc.c
> >>> +++ b/libavcodec/ffv1enc.c
> >>> @@ -672,6 +672,10 @@ static av_cold int encode_init(AVCodecContext *avctx)
> >>>      if ((avctx->flags & (CODEC_FLAG_PASS1|CODEC_FLAG_PASS2))
> >>|| avctx->slices>1)
> >>>          s->version = FFMAX(s->version, 2);
> >>>
> >>> +    // Unspecified level & slices, we choose version 1.2+ to
> >>ensure multithreaded decodability
> >>> +    if (avctx->slices == 0 && avctx->level < 0 &&
> >>avctx->width * avctx->height > 720*576)
> >>> +        s->version = FFMAX(s->version, 2);
> >>> +
> >>>      if (avctx->level == 3 || (avctx->level <= 0 && s->version == 2)) {
> >>>          s->version = 3;
> >>>      }
> >>
> >>Do I understand this correctly to set the bitstream version to "2" if
> >>the resolution is greater than SD?
> >>
> >>If so, I wanted to ask why not set the version to 1.3 directly?
> >
> >there is no reason, its equivalent, the next line will change it to
> >3
> 
> Oh, now I see.
> Thanks for clearing that up for me.
> 
> This auto-level setting is actually a nice thing for applications
> which do not yet offer a switch for choosing FFV1-version, by
> allowing to use them to generate FFV1.3 files.

applied

thanks

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

I do not agree with what you have to say, but I'll defend to the death your
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