How do I detect encode flags like Qpel and N-VOP?

[asanted]

Hello all, I'm in the process of writing a database program along the lines of AMDb, but it will also store audio/video codec information on all programmes stored.

My problem is pulling out video codec data. Using the avi header I can get some details about the video i.e. the codec used, but I can't get the bit rate or various codec flags such as Qpel, and therefore can't indicate whether or not a programme will be suitable for all players.

For testing purposes I used to take the text export from G-spot and use that, but there are bugs in the export.

Can anyone tell me how I can drag this information out of a Divx/Xvid file, I'm currently coding in C++.

Daniel.

[foxyshadis]

You'll have to parse the mpeg4 header inside the bitstream, the avi wouldn't hold any of that. (Also for aspect ratio.) I don't know where to find documentation and some quick searches didn't come up with one, though GPAC (mp4box and other tools) might help there.

[asanted]

Thanks for the reply, I was dreading that answer, I'd better get started.

[movax]

You could try the MediaInfo SDK, either DLL or lib.

[communist]

MPEG4Modifier displays these values too but its written in C# - dont know if its of much help but you can find the binary / source here: http://forum.doom9.org/showthread.php?t=78050

[asanted]

again, thanks for your input.
I've tried Media Info, although it returns alot of information my program already returns that. That info is in the AVI header but the video codec flags like qpel are not (well at least I don't think they are).

Thanks communist, I'll brush up on my C#.