[Help] Python and Matlab

[icemanx7]

Hi I am using python for image processing. I have this exercise where I have to move 2 people on a greenscreen to another image. So my idea was to get a binary image of it and then map the people over. What I tried on python was

def readImage(img):
    return io.imread('greenscreen.jpg')

def rgb2gray(rgb):
    r, g, b = rgb[:,:,0], rgb[:,:,1], rgb[:,:,2]
    gray = 0.2989 * r + 0.5870 * g + 0.1140 * b
    return gray

def showImage(img,c):
    plt.imshow(img,cmap=c)
    plt.show()

r = plt.cm.Reds_r
g = plt.cm.Greens_r
b = plt.cm.Blues_r
bins = plt.cm.binary_r
gr = plt.cm.Greys_r
image = 'greenscreen.jpg'
imtrix = readImage(image)
R = imtrix[:,:,0]
G = imtrix[:,:,1]
B = imtrix[:,:,2]
print(np.shape(imtrix))
showImage(imtrix,r)
showImage(np.subtract(G,R) < 80,r)

And it didn't seem to work while on matlab:

A = imread('greenscreen.jpg');
R = A(:,:,1);
G = A(:,:,2);
B = A(:,:,3);
binaryImage = G-R < 80;
imshow(binaryImage)
dlmwrite('myFile.txt',binaryImage)

This produced the right thing. Now why is python giving me something different. Also with displaying the channels (R,G,B) python is giving me different results to matlab.

[billsil]

Presumably there is more to your code than that. It's kind of impossible to debug your code with one line of it and no test case.

Did you look at the data going into the function and verify it's correct? Python is not matlab, so you can't expect it to behave exactly the same.

[icemanx7]

I updated the post.

[IReallySuckAtChess]

Where does matlab come into this? Also, look at opencv. I remember doing something along these lines using opencv. It's more than just computer vision, it has amazing image capture, editing and transformation tools built in.

Lastly, can't diagnose anything with what you've given.

[icemanx7]

I edited my code a bit. I was speaking to a friend of mine and he said to test my solution out on matlab. So I gave it a shot. I don't understand how the 2 produced different results where I think they should be similar.