How can I creat a window to display the videostream.

[toidi]

I am programming with CVI to control an camera, there is dll i can use, but i need an window to display the videostream, i used the imaqDisPlay function, but it did not work , can anybody help me?

[toidi]

I think the imaqDisPlay function may be having no the function, beacause the help said it is an image window, can an image window display the videostream?

[Dan_Quinn]

Hi Zhao,

Thank you for using our discussion forums! There are a few other options for displaying IMAQ images in CVI. You might try displaying to a Canvas, or if you have Vision, you may use the WindDraw function as well.

A great way to see how this works is to check out some of the CVI example programs that install with IMAQ. Navigate to C:\Program Files\National Instruments\CVI71\samples\IMAQ\ and you will see some good examples that show you how to do this.

Regards

Dan
National Instruments

[toidi]

Hi DannyQ
Thanks for you kindness!
but i think you do not know my meaning. I am programming with CVI to control an camera(not the NI card), there is dll I can use. When I call the functions connecting the device and intilize the parameters, then I can capture pictures, and there is funtion that need a window to display the active movie window, my problem is i do know how to creat a window in cvi which and return the handle of the window. Does CVI have such function? if it does, how to creat a window in cvi?

[Dan_Quinn]

Zhao,

I'm sorry if I assumed it was an IMAQ board. In this case, the only trouble is that we at NI don't know what datastructure your dll uses for the image you are acquiring. Once you know what type of data it is, we would be able to point you to a good display method.

Regards

Dan
National Instruments

[LuisG]

Hello Zhao,

Like Danny mentioned, without knowing the specifics of your camera interface, it's hard to come up with good display suggestions. However, if all you need to do is give a Windows handle to the DLL, then I might be able to help.

For any CVI panel, you can obtain the underlying Windows handle by obtaining the value of the ATTR_SYSTEM_WINDOW_HANDLE panel attribute (with GetPanelAttribute). The main thing to keep in mind is that, not knowing what the camera will do with this window, you should not expect any other CVI controls that you create on this panel to work. The best thing to do might be to simply create an empty panel, separate from any other CVI-specific UI that you might be using.

Luis
NI