How to enumerate MTP and PTP devices

Question

This answer explains how to use WMI to find attached USB mass storage devices by drive letter but I am trying to find the names of (or UNC paths to) attached MTP or PTP devices, such as attached cameras or mobile devices which are mounted without a drive letter, so that I can crawl their directories to search for images. How can I do this?

Answer 1

First of all, you need to understand that having MTP device name will not allow you to crawl it directories or search for images with methods you use for simple PC filesystems. It's only simplified view from Windows Explorer, not really state of things.

I don't know how exeactly do it with Delphi, but there is a Windows Portable Devices API and it all uses COM, so I beleave there is a way to get it works even on Delphi.

Another way you may try, is using libmtp it's a plain C library, you definetely can call it's dll methods from Delphi with some helper code.

If you want just names, you can find names of attached WPD devices (Windows Portable Devices, they are using MTP and PTP protocols) using SetupDiGetDeviceRegistryProperty WinApi function.

First you need to call SetupDiGetClassDevs with GUID_DEVINTERFACE_WPD (it is defined in PortableDevice.h but you can find it easy in google
{6AC27878-A6FA-4155-BA85-F98F491D4F33} )

Then iterate on devices using SetupDiEnumDeviceInfo, get id of each device from WPD cathegory with CM_Get_Device_ID function call and pass it to SetupDiGetDeviceRegistryProperty with SPDRP_FRIENDLYNAME (or SPDRP_DEVICEDESC, maybe you should try different parameters)

There are a lot of samples of using this functions, for example this one: SetupDiGetDeviceProperty usage example