Windows 3.1x via API via MCI 16-bit app 16-bit QTW 2.1 16-bit QTW 2.1 32-bit app NA 16-bit QTW 2.1 Windows 95 via API via MCI 16-bit app 16-bit QTW 2.1 16-bit QTW 2.1 32-bit app 32-bit QTW 2.1 16-bit QTW 2.1 Windows NT via API via MCI 16-bit app 16-bit QTW 2.1 32-bit QTW 2.1 32-bit app 32-bit QTW 2.1 32-bit QTW 2.1
If you only want to develop one version of your application, Windows 3.1's Win32s is the limiting factor. Win32s does not support the multimedia extensions required by QTW and thus does not support use of the 32-bit QTW API.
If you access QTW via MCI, you can write one 32-bit application that will run on all platforms. Your installer will need to install the 16-bit version of QTW under Windows 3.1 and 95, and the 32-bit version under Windows NT.
For Windows 95, regardless of whether your application is 16- or 32-bit, if you only access QuickTime for Windows via MCI, you only need to install 16-bit QTW 2.1. This is because Windows 95 only recognizes 16-bit MCI drivers.
Another option is to write one 16-bit application that accesses QTW via the
16-bit API. This would provide the best QuickTime performance on all platforms
and not require the installer to know what version of Windows it is running
under. 16-bit QTW 2.1 would be installed uniformly across all three Windows
platforms.