IWMReader interface (wmsdkidl.h)

[The feature associated with this page, Windows Media Format 11 SDK, is a legacy feature. It has been superseded by Source Reader and Sink Writer. Source Reader and Sink Writer have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use Source Reader and Sink Writer instead of Windows Media Format 11 SDK, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

The IWMReader interface is used to open, close, start, pause, resume, and unlock the WMReader object. It is also used to stop reading files, and to get and set the output properties.

Many of the methods in this interface are asynchronous and send status notifications to the application through an IWMStatusCallback::OnStatus method implemented in the application.

Inheritance

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

Methods

The IWMReader interface has these methods.

 
IWMReader::Close

The Close method deletes all outputs on the reader and releases the file resources.
IWMReader::GetOutputCount

The GetOutputCount method retrieves the number of uncompressed media streams that will be delivered for the file loaded in the reader.
IWMReader::GetOutputFormat

The GetOutputFormat method retrieves the supported formats for a specified output media stream.
IWMReader::GetOutputFormatCount

The GetOutputFormatCount method is used for determining all possible format types supported by this output media stream on the reader.
IWMReader::GetOutputProps

The GetOutputProps method retrieves the current properties of an uncompressed output stream.
IWMReader::Open

The Open method opens an ASF file for reading.
IWMReader::Pause

The Pause method pauses the current read operation.
IWMReader::Resume

The Resume method starts the reader from the current position, after a Pause method call.
IWMReader::SetOutputProps

The SetOutputProps method specifies the media properties of an uncompressed output stream.
IWMReader::Start

The Start method causes the reader object to start reading from the specified starting time offset. As data is read, it is passed to the application through the application's IWMReaderCallback::OnSample callback method.
IWMReader::Stop

The Stop method stops reading the file.

Requirements

Requirement Value
Target Platform Windows
Header wmsdkidl.h

See also

IWMReaderAdvanced Interface

IWMReaderAdvanced2 Interface

IWMReaderAdvanced3 Interface

IWMReaderAdvanced4 Interface

IWMReaderCallback Interface

IWMReaderCallbackAdvanced Interface

Interfaces

Reading ASF Files