save portion of a waveform chart

[DonyD]

First of all I acquire 2 voltage signals and save them in a file.
The next thing I have to do is to read that file and show a portion of the waveform in a picture inside the page of a tab control, so each page of the tab control has a picture of a different portion of the waveform y different moments.
For example on the page 1, the portion of the waveform from 0 seconds to 2 seconds. The page 2 from 2 seconds to 4 seconds....

What I don´t know how to do is to save that portion of the waveform in a file so i can read it later as an image and put it on a tab control

Thank you.

[smercurio_fc]

Are you using actual picture controls to display these sections? If so, you can use the functions in the Graphics & Sound palette. To write out the images to file use the Picture to Pixmap (you may need to use the Background Color and rect input - use as needed), followed by one of the VIs to write out the graphics file, like Write PNG File. To read in the file and draw it, use the corresponding Read File function, followed by the Draw Flattened Pixmap.


Message Edited by smercurio_fc on 04-22-2008 05:09 PM

[DonyD]

First of all, thank you for your answer.

I display the sections like a picture, but what I don´t  know how to do is to save a portion of the signal acquired in jpeg (for example).            

I mean, I first acquired the voltage signals and I want to save a portion of them in a picture file (for example from 0 seconds to 2 seconds). So when I read the picture file I have like a screenshot of the waveform acquired from 0 to 2 seconds.

I hope I explained it better this time.

[MikeS81]

Hi DonyD,

you can write your waveform data, from the seconds you want to a new waveform graph and use the invoke node to create a picture of it.

Mike

Message Edited by MikeS81 on 04-23-2008 09:30 AM

[smercurio_fc]

Like this:


To get the Invoke node, right-click on the graph and select Create->Invoke Node->Get Image.


Message Edited by smercurio_fc on 04-23-2008 08:25 AM