Providing a UVC INF File

This section illustrates various portions of a device-specific INF file.

An INF file like this one could be used to provide a device-specific name or to register the Extension Unit plug-in.

In general, vendors who supply a setup package can register the plug-in DLL by using the setup package, in which case the vendor does not provide an INF file. For driver signing, it may be easier to provide a setup package instead of a device-specific INF file.

Be aware, however, that you must install this specific sample by using an INF file.

To do so, include the following code in the INF file, here arbitrarily named Xuplgin.inf:

; Copyright (c) CompanyName. All rights reserved.

[Version]
...
Class=Camera
ClassGuid={ca3e7ab9-b4c3-4ae6-8251-579ef933890f}
...

[SourceDisksNames]
1=%Package%

[SourceDisksFiles]
MyPlugin.ax=1

[ControlFlags]
ExcludeFromSelect=*

[DestinationDirs]
MyDevice.CopyList=11    ; %systemroot%\system32 on NT-based systems

[Manufacturer]
%CompanyName%=CompanyName,NT$ARCH$

The device-specific INF file is matched with the device based on the VID/PID identifier. In this case, the device-specific INF file takes precedence over Usbvideo.inf.

[CompanyName.NT$ARCH$]
%MyDevice.DeviceDesc%=MyDevice,USB\Vid_XXXX&Pid_XXXX&MI_XX

[MyDevice]
Include=usbvideo.inf, ks.inf, kscaptur.inf
Needs=USBVideo.NT, KS.Registration, KSCAPTUR.Registration.NT
AddReg=MyDevice.Plugins
CopyFiles=MyDevice.CopyList

Additional sections of Usbvideo.inf need to be included for completeness.

[MyDevice.SERVICES]
Include=usbvideo.inf
Needs=USBVideo.NT.SERVICES

[MyDevice.HW]
Include=usbvideo.inf
Needs=USBVideo.NT.HW

[MyDevice.WDF]
Include=usbvideo.inf
Needs=USBVideo.NT.WDF

[WdmCompanionFilter_CompanionSect]
CompanionServices = SecureUSBVideo

[WdmCompanionFilter_KmdfSvcSect]
KmdfLibraryVersion = %KMDF_VERSION%

[SecureUSBVideo_UmdfSvcSect]
UmdfLibraryVersion = %UMDF_VERSION%
ServiceBinary = %12%\UMDF\SecureUSBVideo.dll
ServiceType = SecureCompanion ; allowed options are: Driver (default), SecureCompanion, NonSecureCompanion
TrustletIdentity = 4096          ; required if it is SecureCompanion

The INF also needs a CopyFiles section to copy the plug-in into the system folder.

[MyDevice.CopyList]
MyPlugin.ax

The first part of the following INF AddReg section registers the plug-in. The remainder of this section shows the registry entries for a node-based Extension Unit plug-in. Refer to Usbvideo.inf for similar examples.

[MyDevice.PlugIns]
HKCR,CLSID\%Plugin.CLSID%,,,%PlugIn_IExtensionUnit%
HKCR,CLSID\%Plugin.CLSID%\InprocServer32,,,MyPlugin.ax
HKCR,CLSID\%Plugin.CLSID%\InprocServer32,ThreadingModel,,Both

; The IID is aggregated onto the node given the GUID of the property set
HKLM,System\CurrentControlSet\Control\NodeInterfaces\%XU_GUID%,,,
   %PlugIn_IExtensionUnit%
; IID in Little-Endian form
HKLM,System\CurrentControlSet\Control\NodeInterfaces\%XU_GUID%,IID,
   1,yy,yy,yy,yy,yy,yy,yy,yy,yy,yy,yy,yy,yy,yy,yy,yy
;CLSID in Little-Endian form
HKLM,System\CurrentControlSet\Control\NodeInterfaces\%XU_GUID%,
   CLSID,1,zz,zz,zz,zz,zz,zz,zz,zz,zz,zz,zz,zz,zz,zz,zz,zz

The following INF section shows how to populate interface-specific registry entries.

[MyDevice.Interfaces]
AddInterface=%KSCATEGORY_CAPTURE%,<Custom GUID/Global>,MyDevice.Interface
AddInterface=%KSCATEGORY_VIDEO_CAMERA%,<Custom GUID/Global>,MyDevice.Interface
AddInterface=%KSCATEGORY_VIDEO%,<Custom GUID/Global>,MyDevice.Interface

[MyDevice.Interface]
AddReg=MyDevice.Interface.AddReg

[MyDevice.Interface.AddReg]
HKR,,CLSID,,%ProxyVCap.CLSID%
HKR,,FriendlyName,,%MyDevice.DeviceDesc%
HKR,,RTCFlags,0x00010001,0x00000010

For USB Cameras, if the device interface registry key location contains a DWORD registry entry EnableDependentStillPinCapture with a non-zero value, the dependent pin on such cameras will be used for photo capture. If the registry entry is not present or set to zero, the dependent pin will not be used. Instead, the photo capture will be done using a frame taken from the preview pin. The following enables dependent still pin capture:

HKR,,EnableDependentStillPinCapture,0x00010001,1

You can also define an optional registry value called UvcFlags. UvcFlags should be a DWORD value. When the device is plugged in, the UVC driver receives a Plug and Play (PnP) Start request. The driver then searches for UvcFlags in the device registry key. The DWORD value is a bitmask and can contain the values in the following table.

Include a line similar to the following example to specify the bitmask to be applied:

HKR,,UvcFlags,0x00010001,0x00000010

If you are using the UVC driver on Windows Server 2003 and Windows Vista or later versions of the operating system, the FID and EOF masks can be used with stream-based formats such as MPEG-2 TS.

In low frame rate conditions, the EOF bit might report completion faster than the FID bit of the following frame. The EOF bit can be used to reduce latency in the delivery of MPEG-2 frames.

For more information about the positional syntax of AddReg directives, see INF AddReg Directive.

This final section supplies missing definitions for the INF.

[Strings]
; Non-localizable
Plugin.CLSID="{zzzzzzzz-zzzz-zzzz-zzzz-zzzzzzzzzzzz}"
ProxyVCap.CLSID="{17CCA71B-ECD7-11D0-B908-00A0C9223196}"
XU_GUID="{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}"
KSCATEGORY_VIDEO_CAMERA="{E5323777-F976-4f5b-9B55-B94699C46E44}"
KSCATEGORY_CAPTURE="{65E8773D-8F56-11D0-A3B9-00A0C9223196}"
KSCATEGORY_VIDEO="{6994AD05-93EF-11D0-A3CC-00A0C9223196}"

; Localizable
CompanyName="CompanyName"
Package="Installation Package"
MyDevice.DeviceDesc="CompanyName Camera"

PlugIn_IMyExtensionUnit="CompanyName Extension Unit Interface"