Rohan12111's profile - activity

Hello, I am relatively new to OpenCV. I have gleaned from tutorials and such that you can crop by using this script:

import cv2
import numpy as np
import video

cam = cv2.VideoCapture(0)
ret,vis = cam.read()    
crop = vis[100:400, 100:300]    
cv2.imshow("Img",vis)
cv2.imshow("Crop",crop)    
cv2.waitKey(0)

And this works fine. I get no errors.

However, when i put it into my main script, it doesn't work, i've narrowed it down to this section of code:

def PicTake(self):
    ret,vis = self.cam.read()
    x1,y1 = self.selection[0]
    x2,y2 = self.selection[1]
    a = 0
    taken = 0
    while taken == 0:
        if cv2.imread("C:\Python27\opencv\samples\python2\Major\Test"+str(a)+".png") == None:
            crop = vis[x1:y1, x2:y2]
            print crop
            cv2.imshow("crop",crop)
            cv2.imwrite("C:\Python27\opencv\samples\python2\Major\Test"+str(a)+".png",crop)
            taken = 1
        else:
            a+=1
    return ("Picture Taken")

where self.selection is just a list of two tuples [(x1,y1),(x2,y2)]. After the first if statement, print crop returns "[]" and empty list.

So yeah, why does it work with numbers and other situations fine, but not here?!

Any help is greatly appreciated, thanks!

Hi there,

I'm using cv2 and python.

I'm trying to change my program from checking two images against each other to checking a video feed against a video. So when i get the cam.read(), how do i change it to the same type of array you get when you cv2.imread() an img.

Thanks, any help is appreciated :)

So you don't know how to call it?

So how would i use cv2 to import cv into the program? Thank you very much :)

Hi there, I'm having trouble looking for a way to install the old cv. If anyone has any ideas how to do it, that would be great! Thanks

Hi there, I'm using cv2 for a school major work. And I was wondering, is there a way to get a cv window into a pygame window. And if not, is there a way to either integrate a cv window into tkinter OR include a GUI interface using cv2 functions.

Thanks for you time.