Notifies a video capture driver to initialize a video device for streaming.
DV_ERR_ALLOCATED | Indicates the specified resource is already allocated. |
DV_ERR_NOMEM | Indicates the driver is unable to allocate or lock memory. |
This message must precede all other streaming messages for a channel.
If a window or callback function will receive callback messages, the device driver uses the following messages to indicate the progress of video input: MM_DRVM_OPEN, MM_DRVM_CLOSE, MM_DRVM_DATA, and MM_DRVM_ERROR.
If a callback function is used, it must reside in a DLL. You do not have to use MakeProcInstance to get a procedure-instance address for the callback function.
For VIDEO_EXTERNALIN channels, DVM_STREAM_INIT triggers capturing of data to the frame buffer.
For VIDEO_EXTERNALOUT channels with overlay capabilities, DVM_STREAM_INIT enables the overlay.
VIDEO_STREAM_INIT_PARMS