Feature extraction and take color histogram

Question

I am working on an image processing feature extraction. I have a photo of a bird in which I have to extract bird area and tell what color the bird has. I used canny feature extraction method to get the edges of a bird.

How to extract only bird area and make the background to blue color?

openCv solution should also be fine.

import skimage
import numpy as np
%matplotlib inline
import matplotlib.pyplot as plt

import os
filename = os.path.join(os.getcwd(),'image\image_bird.jpeg')
from skimage import io
bird =io.imread(filename,as_grey=True)
plt.imshow(bird)

from skimage import feature
edges = feature.canny(bird,sigma=1)
plt.imshow(edges )

Actual bird image can be taken from bird link

Answer 1

1. Identify the edges of your image

2. Binarize the image via automatic thresholding

3. Use contour detection to identify black regions which are inside a white region and merge them with the white region. (Mockup, image may slightly vary)

4. Use the created image as mask to color the background and color it This can be done by simply setting each background pixel (black) to its respective color.

As you can see, the approach is far from perfect, but should give you a general idea about how to accomplish your task. The final image quality might be improved by slightly eroding the map to tighten it to the contours of the bird. You then also use the mask to calculate your color histogram by only taking foreground pixels into account. Edit: Look here:

1. Eroded mask

2. Final image