gpmf_demo.c with time-lapse SEGV / program incompatible?

[time4tea]

Hi,

I'm trying to show the timing and packet information from a time-lapse recording. The recording does appear to have a data stream.

However, the short recordings I have cause a SEGV when using the gpmf_demo.c

The SEGV is caused by a problem in cleanup, with the following sequence of events:

https://github.com/gopro/gpmf-parser/blob/master/demo/GPMF_mp4reader.c#L895

for the time lapse videos, sample count is always 1, while num seems to be the number of frames or something, so always greater than 1.

This causes the loop of entries to exit, without setting mp4->basemetadataduration

The program continues to:

https://github.com/gopro/gpmf-parser/blob/master/demo/GPMF_demo.c#L144

calling:

https://github.com/gopro/gpmf-parser/blob/master/demo/GPMF_mp4reader.c#L1007

which exits with an error condition, jumping to cleanup, which SEGV, in GPMF_FreeCodebook due to ms->cbhandle being improperly initialized in this code path (although this is hard to see because metadata_stream is used uninitialised.

https://github.com/gopro/gpmf-parser/blob/master/demo/GPMF_demo.c#L63

maybe consider something like

GPMF_stream metadata_stream = {0}, ...

(this does in fact fix the SEGV - as now pointers are initialised to 0 - but doesn't fix the parsing issue)

I'm trying to do this to show timing information for meta data streams in the time-lapse footage.

Thanks!

[dnewman-gpsw]

That was bug fixed in the develop branch, I just moved that fix over.

[time4tea]

Awesome. Thanks for merging the fix.