where is write the CLSID of a directshow filter?

Question

please consider the microsoft "AVI mux" directshow filter, it have CLSID: {E2510970-F137-11CE-8B67-00AA00A3F1A6}

suppose that, just for an experiment, I want to change this code. I opened the file qcap.dll with WinHex qcap.dll but I can not find this string inside it, then I wonder where is written, if it's written in qcap.dll. Thanks

Answer 1

It is there but it is not a string, it is hardcoded as a binary value. Then you are to consider registration of the DLL, which stands alone from file contents. Whatever you are trying to achieve patching a stock DLL, it is wrong and a no-go for a real task. Not to mention that the file is proceted by System Restore and reversing is likely to be an EULA violation.