blob detection with dfs

Author: invigorzz313

Blob Detection/BlobDetection.py

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+import  cv2
+from tkinter.filedialog import *
+
+
+# we will find number of blobs with pixel value 255 in the following image
+
+# finding binary image
+print("\nImage should preferably be white (lighter) blobs on black (darker) background ")
+photo = askopenfilename()
+img = cv2.imread(photo,cv2.IMREAD_GRAYSCALE)
+img = cv2.resize(img,(300,300))
+n,l = img.shape 
+count = 0
+
+# blur the image
+ksize = (5,5) # kernel size
+img = cv2.blur(img,ksize)
+
+# thresholding the image
+for i in range(n):
+    for j in range(l):
+        if(img[i,j]<=127):
+            img[i,j]=0
+        else:
+            img[i,j]=255
+
+def dfs(i,j):
+    img[i,j]=127 # implying that we have visited this pixel for further reference
+    if (i-1>=0):
+        if(img[i-1,j]==255):
+            dfs(i-1,j)
+    if (j-1>=0):
+        if(img[i,j-1]==255):
+            dfs(i,j-1)
+    if (j+1<l):
+        if(img[i,j+1]==255):
+            dfs(i,j+1) 
+    if (i+1<n):
+        if(img[i+1,j]==255):
+            dfs(i+1,j)
+    if((i-1>=0) and (j-1>=0)):
+        if(img[i-1,j-1]==255):
+            dfs(i-1,j-1)
+    if((i-1>=0) and (j+1<l)):
+        if(img[i-1,j+1]==255):
+            dfs(i-1,j+1)
+    if((i+1<n) and (j-1>=0)):
+        if(img[i+1,j-1]==255):
+            dfs(i+1,j-1)        
+    if((i+1<n) and (j+1<l)):
+        if(img[i+1,j+1]==255):
+            dfs(i+1,j+1)
+
+cv2.namedWindow('image',cv2.WINDOW_NORMAL)
+cv2.imshow("image",img)
+cv2.waitKey(1000)
+
+
+for i in range(n):
+    for j in range(l):
+        if(img[i,j]==255):
+            count += 1 #to count number of white blobs
+            dfs(i,j) 
+
+print("count is",count)

Blob Detection/ReadMe.md

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+# Blob detection
+This python script finds blobs in an image using DFS algorithm. 
+
+## Setup Instructions
+### Install python3
+sudo apt-get install python3
+### Install pip (package installer for python)
+sudo apt-get install python3-pip
+### Install OpenCV library with pip
+pip3 install opencv-python
+### Install tkinter library
+sudo apt-get install python3-tk
+
+## Details/Output
+The program asks user to select an image to count the number of blobs.  
+The image should preferably have **lighter blobs on a darker background**.  
+Eg. white blobs on a black background  
+The output is the count of blobs in the image.
+
+## Author
+Github: invigorzz313