DirectShow samples lived under (SDK samples root)\DirectShow\ in the Windows 7.1 SDK, but the Windows 8 SDK does not have the files neither in C:\Program Files (x86)\Windows Kits\8.0 nor C:\Program Files (x86)\Microsoft SDKs\Windows. The samples are also not for download at http://code.msdn.microsoft.com/windowsapps
I believe DirectShow is to be phased out and replaced by Microsoft Media Foundation (MF). I think that's been the intention since Windows Vista, although at that time MF was not capable enough to replace DirectShow. Microsoft representatives have stated that DirectShow will not be supported in Metro UI apps.
I think dshow.h, quartz.dll, etc. are still in the Window 8 SDK kit. However, while Windows 8 will still run DirectShow programs in a normal desktop, it might be that DirectShow samples will never be included in the Windows 8 SDK or new Windows Dev Center because it is considered deprecated. I could not find anything stating this definitively, but most information about MF seems to indicate that DirectShow is not a way forward, and there was a lot of clean-up and removal of obsolete artifacts from the Windows 8 SDK.
Anecdotal References:
Related Download Links:
Fwiw, there are a few unofficial samples using DirectShow in the Windows Dev Center.
Microsoft now has a github repo with the old samples: https://github.com/Microsoft/Windows-classic-samples/tree/master/Samples/Win7Samples/multimedia/directshow/baseclasses
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With