is there any way to get the frame type (P and B) after calling
av_read_frame(pFormatCtx, &avPacket) on an Mpeg2 file?
I only know, that if(avPacket.flags) I've got an I-frame. And if I could
rely upon dts and pts, I think it should be possible to decide, what's a
P- and a B-frame. But I can't.