[FFmpeg-devel] debuggin ffmpeg

[Maxim Polijakowski]

Am 18.02.2014 11:41, schrieb Wolfgang Haupt:
> Hi ffmpeg-devs,
>
> I'm quite new to ffmpeg just trying to figure out how the mpegts 
> demuxer works in detail.
> Therefore I started debugging into ffprobe (-show_frames).
> However I wonder how you guys do debugging because every second 
> variable is optimized out.
> I guess optimizing is rather important in ffmpeg, so I'd like to ask 
> if it's safe to disable optimizing for debug builds?

I debug the ffmpeg executable quite often. Below the description of how 
I do that:

1) obtain the debug build by running

cd [path/to/your/ffmpeg/local/clone]
./configure --enable-debug=3 --disable-optimizations --disable-inline-asm
make

2) fire up GDB and type in the following commands:

gdb [path/to/ffmpeg/executable]
set args -i [path/to/input/file] test.avi [or some other output file or 
null]
break libavformat/mpegts.c:135 [or some other line]
run

Surely, you can do the same with ffprobe and use another debugger...

Best regards
Maxim