Freeing SyntheticSampleTable

[michaeljoelphillips]

Greetings,

I am encountering a Segfault when attempting to delete a pointer to a SyntheticSampleTable object. I am trying to cleanup inputs and a SampleTable for an application that processes multiple inputs when it Segfaults. I've done a few tests with the Mp4Mux application and can replicate the issue with the SyntheticSampleTable object there as well. I couldn't find any examples of what I'm needing so I'm not sure if deleteing the pointer is the right solution to being with.

Any and all help is appreciated!

[barbibulle]

deleting a SyntheticSampleTable object is a valid operation. When you do this, it will decrement the ref count of all the AP4_Sample objects referenced by the table. So this may be a case of improper reference counting of sample data (maybe one-too-many call to Release()), but it could be a bug lurking somewhere in the SyntheticSampleTable code. If you can share a description of how to reproduce the issue, I can take a look.

[michaeljoelphillips]

I think I actually found my issue. The AP4_Track was scoping out before I was deleting the SampleTable object. If I understand this correctly, the AP4_Track destructor frees the SampleTable object so it looks like I was trying to delete a pointer to an object that was already freed. If I have any other issues, I'll check back but it seems to have fixed it for now. Thanks for your help!

[barbibulle]

Yes, the AP4_Track constructor takes ownership of the AP4_SampleTable that's passed to it.