How to crop video using ROI

[joycejoy86]

Hello,

Would some one please help me?

I have a loop which continuously aquire images from a camera and saves it to a video . I would like to crop a region of this video by passing the co-ordinates of a rectangle.After I have the cropped video, I would like to do a intensity profile of the whole video and display it using a single graph ( intesnity changes for diffferent frames in the y axis and the the number of the frame in x - axis.

Joyce Joy

[Phil_]

I think you will have to crop each frame individually. Use the IMAQ extract VI (http://zone.ni.com/reference/en-XX/help/370281P-01/imaqvision/imaq_extract/)

Depending on the frame rate of your video capture, will determine if you can do this live or offline.

(I usually work with still images, and not continuous video)

[soumendras]

Did you get the answer to your question..I want to do the same thing...please send me the program if you got the solution

[MariusU]

Hi,

You can implement image cropping following the example:
https://decibel.ni.com/content/docs/DOC-11222

You would have to programmatically generate the ROI rectangle if you do not wish to have user interaction in the code.

I am not quite sure what kind of intensity profile you want, but here is a good example that performs it along a line, so you could just build an array of those and plot it.
https://decibel.ni.com/content/docs/DOC-20840

Hope this helps!