[FFmpeg-devel] [PATCH] avcodec/ffv1dec: fix some unsupported pix_fmt

[Michael Niedermayer]

On Mon, Jun 13, 2016 at 07:31:15PM +0200, Jerome Martinez wrote:
> FFV1 decoder:
> 
> When checking pix_fmt mapping, some bitstreams are mapped to an
> incorrect pix_fmt instead of being rejected (ENOSYS).
> Actually, such bitstreams are not supported (FFmpeg encoder does not
> produce such bitstream, such bitstream may come only from another
> encoder for the moment).
> 
> - JPEG 2000 RCT 11/13/15/16 bit depths are mapped to a 8-bit FFmpeg
> pix_fmt (e.g. bgr0), which is not expected.
> - JPEG 2000 RCT 9/10/12/14 bit depths with alpha are mapped to a
> FFmpeg pix_fmt without alpha (e.g. AV_PIX_FMT_GBRP9 for 9-bit with
> alpha), which is not expected.
> 
> The order for choosing the pix_fmt is changed to the one used by
> YCbCr selection (<=8 bit first).
> " && !f->transparency" is added to the other lines.
> 

>  ffv1dec.c |   15 ++++++++-------
>  1 file changed, 8 insertions(+), 7 deletions(-)
> 27efc1a9821576a2a5bd8d1feaaf6c584fc69a62  0001-avcodec-ffv1dec-fix-some-unsupported-pix_fmt.patch
> From 90bfd748b0e25d7a0be037280f4a0a40242f8d27 Mon Sep 17 00:00:00 2001
> From: =?UTF-8?q?J=C3=A9r=C3=B4me=20Martinez?= <jerome at mediaarea.net>
> Date: Mon, 13 Jun 2016 19:18:22 +0200
> Subject: [PATCH] avcodec/ffv1dec: fix some unsupported pix_fmt
> MIME-Version: 1.0
> Content-Type: text/plain; charset=UTF-8
> Content-Transfer-Encoding: 8bit
> 
> Signed-off-by: Jérôme Martinez <jerome at mediaarea.net>
> ---
>  libavcodec/ffv1dec.c | 15 ++++++++-------
>  1 file changed, 8 insertions(+), 7 deletions(-)
> 
> diff --git a/libavcodec/ffv1dec.c b/libavcodec/ffv1dec.c
> index d2bf3a8..6a932b2 100644
> --- a/libavcodec/ffv1dec.c
> +++ b/libavcodec/ffv1dec.c
> @@ -768,17 +768,18 @@ static int read_header(FFV1Context *f)
>                     "chroma subsampling not supported in this colorspace\n");
>              return AVERROR(ENOSYS);
>          }
> -        if (     f->avctx->bits_per_raw_sample ==  9)
> +        if (     f->avctx->bits_per_raw_sample <=  8 && !f->transparency)
> +            f->avctx->pix_fmt = AV_PIX_FMT_0RGB32;
> +        else if (f->avctx->bits_per_raw_sample <=  8 && f->transparency)
> +            f->avctx->pix_fmt = AV_PIX_FMT_RGB32;
> +        else if (f->avctx->bits_per_raw_sample ==  9 && !f->transparency)
>              f->avctx->pix_fmt = AV_PIX_FMT_GBRP9;
> -        else if (f->avctx->bits_per_raw_sample == 10)
> +        else if (f->avctx->bits_per_raw_sample == 10 && !f->transparency)
>              f->avctx->pix_fmt = AV_PIX_FMT_GBRP10;
> -        else if (f->avctx->bits_per_raw_sample == 12)
> +        else if (f->avctx->bits_per_raw_sample == 12 && !f->transparency)
>              f->avctx->pix_fmt = AV_PIX_FMT_GBRP12;
> -        else if (f->avctx->bits_per_raw_sample == 14)
> +        else if (f->avctx->bits_per_raw_sample == 14 && !f->transparency)
>              f->avctx->pix_fmt = AV_PIX_FMT_GBRP14;
> -        else
> -        if (f->transparency) f->avctx->pix_fmt = AV_PIX_FMT_RGB32;
> -        else                 f->avctx->pix_fmt = AV_PIX_FMT_0RGB32;

an else "error" feels missing
pix_fmt would not be initialized after the patch

[...]


-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

The worst form of inequality is to try to make unequal things equal.
-- Aristotle
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 181 bytes
Desc: Digital signature
URL: <http://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20160613/7385bd00/attachment.sig>