Raspberry Pi - Image processing for UAV navigation

RE: Raspberry Pi - Image processing for UAV navigation

e14 Contributor — Sun, 15 Nov 2015 13:46:44 GMT

Need help in image processing by pi 2.

Regards

Hassan mughal

RE: Raspberry Pi - Image processing for UAV navigation

e14 Contributor — Mon, 18 Feb 2013 21:27:09 GMT

Changed to a discussion

http://www.element14.com/community/message/69975#69975/l/re-raspberry-pi-webcam-python-opencv-weird-problems-no-solutions

RE: Raspberry Pi - Image processing for UAV navigation

e14 Contributor — Mon, 18 Feb 2013 01:16:11 GMT

Now, That TakePic function works really well thankyou, so this is my code below. I run the program and can see the webcam feed, I then press a key capturing an image as img1, then again but as img2, and again img3. Now when the final image displays (img2+img3) it just shows img3 added to itself, i.e. as though I coded Add(img3,img3,img1). I have also tried AddWeighted and AND functions.

I have tried and tried and cannot find the problem, is it the Add function that is not reading img2, or could img2 not be saved properly? or what is going on!!

Any help would be great,

Cheers,

Dan.

# Daniel Myers
# cvTest.py
# 18 Feb 13

from cv import *

SIZE=(HEIGHT,WIDTH)=(640,480) # Image capture size
CAMERA_INDEX=-1 # -1 means any camera attached

def TakePic(cam):
    NamedWindow('cvTest',CV_WINDOW_AUTOSIZE)
    while True:
        img=QueryFrame(cam)
        ShowImage('cvTest',img)
        k=WaitKey(2)
        if k>=0:
            return img

cam=CaptureFromCAM(CAMERA_INDEX) # Initializes capturing a video from a camera
SetCaptureProperty(cam,CV_CAP_PROP_FRAME_WIDTH,WIDTH) # Set the capture image width
SetCaptureProperty(cam,CV_CAP_PROP_FRAME_HEIGHT,HEIGHT) # Set the capture image height

img1=TakePic(cam)
ShowImage('img1',img1)

img2=TakePic(cam)
ShowImage('img2',img2)

img3=TakePic(cam)
ShowImage('img3',img3)

AddWeighted(img2,0.4,img3,0.6,20,img1)
ShowImage('img2+img3',img1)

k=WaitKey(100000)
DestroyAllWindows()
del(cam)

RE: Raspberry Pi - Image processing for UAV navigation

e14 Contributor — Sun, 17 Feb 2013 09:27:29 GMT

Thanks Eduardo,

I have been away for the weekend but will be trying out your code tomorrow, it looks like that may fix my problem, or maybe I really want it to.

James, think that link is broken now, did you mean Texas in QLD or USA?

Anyway, I'll be on tomorrow to reveal if the problem is fixed and if so I'll post the max frames per second I can get my program running at.

Cheers,

Dan

RE: Raspberry Pi - Image processing for UAV navigation

e14 Contributor — Sat, 16 Feb 2013 06:18:10 GMT

I hope you don't live in Texas. Although, it is a great Q.

http://www.popsci.com/technology/article/2013-02/privacy-and-drones

RE: Raspberry Pi - Image processing for UAV navigation

e14 Contributor — Wed, 13 Feb 2013 21:32:24 GMT

Hi all,

I have got openCV working for python and C, just using python for now. But I have ran into problems and need help since I've tried everywhere and everything I can think of.

-Using python with openCV but can use C instead
-Running Raspberry Pi, 512Mb model B
-Using a logitech QuickCam Communicate MP/S5500 Webcam

Now, my ultimate goal is to capture an image, wait some time, capture another image, merge (add) the images together, save the output.

The issue is the second image captured is just like the first, dispite the program correctly waiting, the camera does not wait to capture the next image. I have tried in both python and C and had the same issue so I believe I must be missing some key element.

Here is the Code:

# PudFish
# cvTest.py
# 11 Feb 13
from cv import *
SIZE=(HEIGHT,WIDTH)=(640,480) # Image capture size
CAMERA_INDEX=-1 # -1 means any camera attached
WAIT_TIME=10 # In seconds
cam=CaptureFromCAM(CAMERA_INDEX) # Initializes capturing a video from a camera
SetCaptureProperty(cam,CV_CAP_PROP_FRAME_WIDTH,WIDTH) # Set the capture image width
SetCaptureProperty(cam,CV_CAP_PROP_FRAME_HEIGHT,HEIGHT) # Set the capture image height
img1=QueryFrame(cam) # Capture an image and store as img
print "img1 captured"
SaveImage("img1.png",img1) # Save the img to file
print "img1 saved"
# Delay, indexed for debugging
for i in range(0,WAIT_TIME):
print "i: %d" %i # Print the current index
WaitKey(1000)

img2=QueryFrame(cam) # Capture an image and store as img
print "img2 captured"
SaveImage("img2.png",img2) # Save the img to file
print "img2 saved"
# Print the data types and ID's for debugging
print "img1 Type: %s" %type(img1) # Print the data type of the img variable
print "img1 ID: %d" %id(img1) # Print the unique ID of the img1 object
print "img2 Type: %s" %type(img2) # Print the data type of the img variable
print "img2 ID: %d" %id(img2) # Print the unique ID of the img2 object

And the Output:

VIDIOC_QUERYMENU: Invaild argument
VIDIOC_QUERYMENU: Invaild argument
VIDIOC_QUERYMENU: Invaild argument
VIDIOC_QUERYMENU: Invaild argument
VIDIOC_QUERYMENU: Invaild argument
VIDIOC_QUERYMENU: Invaild argument
VIDIOC_QUERYMENU: Invaild argument
VIDIOC_QUERYMENU: Invaild argument
VIDIOC_QUERYMENU: Invaild argument
VIDIOC_QUERYMENU: Invaild argument
VIDIOC_QUERYMENU: Invaild argument
VIDIOC_QUERYMENU: Invaild argument
VIDIOC_QUERYMENU: Invaild argument
VIDIOC_QUERYMENU: Invaild argument
img1 captured
img1 saved
i: 0
i: 1
i: 2
i: 3
i: 4
i: 5
i: 6
i: 7
i: 8
i: 9
img2 captured
img2 saved
img1 Type: <type 'cv2.cv.iplimage'>
img1 ID: 1147448688
img2 Type: <type 'cv2.cv.iplimage'>
img2 ID: 1147448712

So, I had the webcam facing the monitor for debugging:

-img1 shows the last line as "VIDIOC_QUERYMENU: Invaild argument"
-img2 shows the last line as "i: 2"

Now the odd thing which occurs, I comment out the capturing of img1, and then img2 is captured at the correct time, i.e. the last line in the picture is i: 9

Let me know if you need any more info or to clear things up, thanks in advance for any help.

Dan.

RE: Raspberry Pi - Image processing for UAV navigation

eduardofv — Wed, 13 Feb 2013 15:13:11 GMT

Hope this posts I wrote (a while ago) may help:

http://eduardofv.com/read_post/185-Installing-OpenCV-on-the-Raspberry-Pi

http://eduardofv.com/read_post/192-OpenCV-on-the-Raspberry-Pi-with-Arch-Linux-ARM

http://eduardofv.com/read_post/194-A-Laser-Range-Finder-using-RapsberryPi-Arduino-and-OpenCV

Let me tell you that a USB camera is pretty slow (usually no more than 3fps). I'm waiting for the CSI camera to be released.

Regards,

Eduardo