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IWMDRMTranscryptor interface

[IWMDRMTranscryptor is available for use in the operating systems specified in the Requirements section. It may be altered or unavailable in subsequent versions. Instead, use Microsoft PlayReady. ]

The IWMDRMTranscryptor interface transforms a DRM-protected ASF file into a secure data stream conforming to the Windows Media DRM 10 for Network Devices protocol. The resulting stream can be sent to devices that support Windows Media DRM 10 for Network Devices.

IWMDRMTranscryptor is the primary interface of the DRM transcryptor object. You can obtain a pointer to an instance of this interface by calling the WMCreateDRMTranscryptor function.


The IWMDRMTranscryptor interface inherits from the IUnknown interface. IWMDRMTranscryptor also has these types of members:


The IWMDRMTranscryptor interface has these methods.


Removes the file from the transcryptor and releases all associated resources.


Loads a file into the transcryptor.


Generates encrypted data for streaming to devices that support Windows Media DRM 10 for Network Devices from the file loaded in the transcryptor.


Sets the transcryptor to a point in the data stream of the loaded ASF file. Subsequent reads will begin from this point in the file.



The DRM transcryptor is initialized after a policy request message is sent by a device. You can parse a license request and obtain the device certificate, the device serial number, and the requested action by calling IWMDRMMessageParser::ParseLicenseRequestMsg.

The methods of the IWMDRMTranscryptor interface use the IWMStatusCallback::OnStatus callback method to inform the application of progress. For more information, see Using the Callback Methods.


Minimum supported client

Windows XP [desktop apps only]

Minimum supported server

Windows Server 2003 [desktop apps only]

See also