[Libav-user] (AVStream *)av_malloc(sizeof(AVStream)) crashed the application

Wenpeng Zhou zhou.wenpeng at rdnet.fi
Tue Oct 30 12:34:58 CET 2012

Hi Chandranath and Geek.Song



I see.


I fixed as your suggested.


From: libav-user-bounces at ffmpeg.org [mailto:libav-user-bounces at ffmpeg.org]
On Behalf Of Chandranath Bhattacharyya
Sent: 30. lokakuuta 2012 13:28
To: This list is about using libavcodec, libavformat, libavutil, libavdevice
and libavfilter.
Subject: Re: [Libav-user] (AVStream *)av_malloc(sizeof(AVStream)) crashed
the application


>> Hi Chandranath


>> Thanks!


>> But I already allocated memory for the pointer *ic_enc_mjpeg

                OK. Sorry. I did not realize you meant the crash occurred
even after allocation.


>> AVFormatContext *ic_enc_mjpeg;

>> ic_enc_mjpeg = (AVFormatContext *)av_malloc(sizeof(AVFormatContext));


>> Then I tried to allocate the memory for ic_enc_mjpeg->streams[0], then it


streams variable inside AVFormatContext is AVStream **. So the allocation of
AVFormatContext using av_malloc is not supposed to initialize/allocate it.
Hence the crash.


Check the documentation in header avformat.h for more info. 


The crash can be fixed by the following code. 


AVFormatContext *ic_enc_mjpeg;

ic_enc_mjpeg = (AVFormatContext *)av_malloc(sizeof(AVFormatContext));

ic_enc_mjpeg->streams = (AVStream **)av_malloc(sizeof(AVStream *)); // ç DO

ic_enc_mjpeg->nb_streams = 1; // OR WHATEVER.

ic_enc_mjpeg->streams[0] = (AVStream *)av_malloc(sizeof(AVStream));





-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://ffmpeg.org/pipermail/libav-user/attachments/20121030/662fed96/attachment.html>

More information about the Libav-user mailing list