DirectShow dynamically changes the media type dynamic format changes

Among the three filter types of DS, trans are generally considered to be the easiest to write, and it is easy to write a demo. However, if you want to write a trans, you should pay attention to it, in particular, dynamic format changes, which I think is the most troublesome. for top-to-bottom requests, bottom-to-top requests, the buffer size changes .... and so on. If you do not handle the issue, the memory access is in violation, and a bunch of problems will occur.

 

Recently I wrote a trans, and I think it takes the most time to deal with this, but it is better that it has finally been completed.