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IDrawVideoImage Interface

 
Microsoft DirectShow 9.0

IDrawVideoImage Interface

  • **Note   **This interface has been deprecated. New applications should not use it.

The IDrawVideoImage interface enables an application to draw the same video image in multiple places simultaneously on the screen. The Video Renderer filter exposes this interface. The Video Mixing Renderer (VMR) filter provides a better way to accomplish the same effect, through the use of multiple input streams.

To use this interface, call DrawVideoImageBegin to put the Video Renderer into GDI mode. Then the application can call the DrawVideoImageDraw method as often as necessary. The renderer simply takes the current video frame and draws it to the specified rectangle. This process is asychronous to the delivery of frames to the renderer on the filter graph thread. The application is responsible for the frame rate at which it renders images; this rate will never be the same as the rate of the frames being delivered to the filter. In other words, calling this method is like taking a periodic shapshot of the video and putting it into a device context of your choosing at a rate of your choosing.

In addition to the methods inherited from IUnknown, the IDrawVideoImage interface exposes the following methods.

Methods Description
DrawVideoImageBegin Turns off DirectDraw in preparation for a call to DrawVideoImageDraw.
DrawVideoImageDraw Draws the specified source rectangle to the specified destination rectangle in the specified GDI device context.
DrawVideoImageEnd Turns DirectDraw back on after drawing has been performed.

See Also