[FFmpeg-devel] [PATCH 12/19] avcodec/mpegvideo_enc: Don't segfault on unorthodox mpeg_quant

Michael Niedermayer michael at niedermayer.cc
Thu Apr 8 00:05:27 EEST 2021

On Tue, Apr 06, 2021 at 11:55:09PM +0200, Andreas Rheinhardt wrote:
> The (deprecated) field AVCodecContext.mpeg_quant has no range
> restriction; MpegEncContext.mpeg_quant is restricted to 0..1.
> If the former is set, the latter is overwritten with it without
> checking the range. This can trigger an av_assert2() with the MPEG-4
> encoder when writing said field.
> Fix this by just setting MpegEncContext.mpeg_quant to 1 if
> AVCodecContext.mpeg_quant is set.
> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
> ---
> This can not be triggered if one only sets options via the dictionary in
> avcodec_open2(); one needs to set it directly in the AVCodecContext or
> use the private class of AVCodecContext.

I tend toward checking mpeg_quant to be valid in init somewhere but this
here is fine too or in addition


Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

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