The MM_DRVM_OPEN callback message notifies a client that a user-mode video capture driver has finished processing a DVM_STREAM_INIT message.
Parameters
dwMsg
MM_DRVM_OPEN
dwParam1
Not used.
dwParam2
Not used.
Comments
A user-mode video capture driver sends an MM_DRVM_OPEN message to its client, by means of a callback, when the driver finishes processing a DVM_STREAM_INIT message. The driver sends the message to the client by calling DriverCallback, passing the specified parameters.
The driver sends the MM_DRVM_OPEN message only if the client has specified a notification target with the DVM_STREAM_INIT message.
Drivers using VCUser.lib do not have to call DriverCallback to send callback messages. Code within VCUser.lib handles delivery of callback messages for the driver.
For more information about notifying clients, see Notifying Clients from Video Capture Drivers.