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Flora
May 21, 2004, 09:34:25
Hi, I am very new to MontiVision.
I have just installed the evaluation version.
The filters are very impressive, however, I need to extend some of the functionalities.
Can the filters be extended from the C++ code?
For example, can I extend MVTextOverlay?
Do I need to use inheritance in the code generated from the MontiVision Filter Wizard, or I need to write a new transform filter using DirectShow SDK together with MVFilterSDK?
If this can happen, I will really consider to buy the full version.
Thanks.

Cheers,
Flora

Bernd Peretzke
May 24, 2004, 18:02:23
Hi,

What do you want do do?

You can create new filter with the MV Filter SDK (Wizard) but you can't extend MV Imaging Filters with the Filter SDK like C++ inheritance. To create new filters you doesn't need the DirectShow SDK.

You can extend filter functions during image processing with the filter events mechanism. You can get processed data from the filter with the filter interfaces. Look at the FindObject Sample how to use filter events.

To extend the MV Text Overlay Filter you can use the MV GDI Overlay filter to draw additional objects into the video stream with GDI functions (Look at the LiveDraw sample).

Regards
Bernd Peretzke

Flora
June 1, 2004, 03:11:31
Thanks for your reply.
But what I need to do is not only to create a filter that can be used within the filter graph of DirectX SDK, but to create a transform filter that has can work as a plug-in for Windows Media Encoder.

That means the filter needs to inherit from CTransformFilter or CTransInPlaceFilter interface from DirectX SDK, and at the same time I would like it to have the functionalities of MVTextOverlay and get the text input from a socket (the filter will also act as a server for incoming sockets).

Is that possible?

Thanks.

Marc Cymontkowski
June 2, 2004, 09:08:27
Hi,

Our filters are 100% DirectShow compatible filters, inherited from CTransformFilter.

Isn't it possible to receive the data from the socket within the application and then to give it to the MV Text Overlay filter?


Best Regards,

Marc Cymontkowski

Flora
June 2, 2004, 16:17:27
Hi,
I fully understand what you mean.
But what I need at this stage is not to build an application or to build DirectShow filters that will interact with other filters in the graph edit.
I need to build some filters (stand-alone registered filters) that should act as Windows media encoder plug in (which should be implemented a DirectX transform filter). Why? Because Windows media encoder needs a CTransformFilter interface in the registered dll to recognise that it can act as a plug-in.

That's why transform filters need to expose CTransformFilter interface. I have tried the evaluation versions of Montivision, and many features there are basically what I need to implement. The only sad thing is if I can't extend the interfaces to be transform filters with direct inheritance to CTransformFilter.

Thanks.