[FFmpeg-devel] [PATCH] mpegtsenc: fix free of adts when not using AAC
bitbytebit at groovy.org
Fri Oct 21 15:05:47 CEST 2011
On Wed, Oct 19, 2011 at 4:10 PM, Michael Niedermayer <michaelni at gmx.at>wrote:
> On Wed, Oct 19, 2011 at 12:12:25AM -0500, Chris Kennedy wrote:
> > On Tue, Oct 18, 2011 at 8:05 PM, Michael Niedermayer <michaelni at gmx.at
> > > On Wed, Oct 12, 2011 at 09:59:44PM -0500, Chris Kennedy wrote:
> > > > On Wed, Oct 12, 2011 at 10:18:22PM +0000, Carl Eugen Hoyos wrote:
> > > > > Chris Kennedy <bitbytebit <at> gmail.com> writes:
> > > > >
> > > > > Please upload the sample that triggers the segfault for you.
> > > >
> > > > It's actually from a live stream from a clearQAM mpegts broadcast,
> > > > so unfortunately has been impossible to get a file that triggers it.
> > > > It's rare, once every week, and when it happens backtraces always
> > > > point into libavformat somewhere from either the write trailer
> > > > function or read frame function. Here's the two backtraces I've
> > > > gotten, always seems to be when closing an output context and opening
> > > > a new one for mpegts.
> > >
> > > if you cannot upload a sample then maybe running the stuff under
> > > valgrind might point more clearly to the cause
> > >
> > >
> > This is what it does under valgrind: This is the write frame one that
> > happens, reading clearQAM HD signals over udp and from clearQAM cards.
> > There's also a av_read_frame issue too that seems to be either the
> > parser doing something odd or somehow the input context streams changing.
> > Often times from what I can tell basically when the stream is very
> > 'corrupted' then these cause the input context to get confused (thinking
> > audio codec or settings suddenly change, they don't, and new streams keep
> > appearing). Then output wise as below, it seems suddenly the packet
> > has some frames possibly that have a fully negative large stream index
> > and those cause a crash from trying to reference a stream with them as
> > index. So just seems like the whole internal system is being somewhat
> > thrashed by the mpegts packets, admittedly from a probably bad input
> > clearQAM signal.
> I tried to fix the issue valgrind pointed too, please test and report
> if the change fixed it or if theres some issue left
Reporting back that your patch has fixed this issue entirely. Demuxing is
now able to handle mpegts that was giving segfaults and double free's every
8 to 12 hours before. Thanks for getting this to work!
> Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
> The real ebay dictionary, page 3
> "Rare item" - "Common item with rare defect or maybe just a lie"
> "Professional" - "'Toy' made in china, not functional except as doorstop"
> "Experts will know" - "The seller hopes you are not an expert"
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
More information about the ffmpeg-devel