[FFmpeg-devel] [PATCH] mpegts: prevent division by zero

[Andreas Cadhalpun]

On 08.11.2016 21:09, Michael Niedermayer wrote:
> On Tue, Nov 08, 2016 at 07:47:02PM +0100, Andreas Cadhalpun wrote:
>> On 08.11.2016 00:54, Michael Niedermayer wrote:
>>> On Mon, Nov 07, 2016 at 11:49:52PM +0100, Andreas Cadhalpun wrote:
>>>> Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun at googlemail.com>
>>>> ---
>>>>  libavformat/mpegts.c | 4 ++++
>>>>  1 file changed, 4 insertions(+)
>>>>
>>>> diff --git a/libavformat/mpegts.c b/libavformat/mpegts.c
>>>> index fad10c6..77d63f2 100644
>>>> --- a/libavformat/mpegts.c
>>>> +++ b/libavformat/mpegts.c
>>>> @@ -2692,6 +2692,10 @@ static int mpegts_read_header(AVFormatContext *s)
>>>>          /* NOTE1: the bitrate is computed without the FEC */
>>>>          /* NOTE2: it is only the bitrate of the start of the stream */
>>>>          ts->pcr_incr = (pcrs[1] - pcrs[0]) / (packet_count[1] - packet_count[0]);
>>>> +        if (ts->pcr_incr <= 0) {
>>>> +            av_log(s, AV_LOG_ERROR, "invalid pcr increment %d\n", ts->pcr_incr);
>>>> +            return AVERROR_INVALIDDATA;
>>>> +        }
>>>
>>> if a pcr pair is bad i would suggest to run the loop by another
>>> iteration
>>
>> That's a good idea. New patch attached.
> 
> LGTM, maybe add a av_log() so the user knows of the issue

Makes sense, patch with added log message is attached.

> (especially
> if all pcr are systematically bad, n which case this would need to be
> adjusted to not fail)

What do you think should be done in that case?

Best regards,
Andreas
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