Signature verification using opencv

srajangupta144 · Oct 14, 2024 · e133134 · e133134
1 parent 847b0f8
commit e133134
Show file tree

Hide file tree

Showing 9 changed files with 225 additions and 0 deletions.
diff --git a/Signature Verification/Readme.md b/Signature Verification/Readme.md
@@ -0,0 +1,19 @@
+### Signature Verification System
+This project is a web-based Signature Verification System built using Flask and OpenCV. It allows users to upload two signature images, compares them, and verifies if the signatures are likely from the same person based on a similarity score.
+
+### Features
+Upload two signature images.
+Real-time comparison using OpenCV's image processing techniques.
+Displays the result indicating whether the signatures are likely the same.
+Simple and intuitive web interface.
+Result shown in bold text for easy identification.
+
+### Technologies Used
+Python (Flask, OpenCV, NumPy)
+HTML/CSS/JavaScript
+Jinja2 (Flask templating engine)
+
+### How to Use
+Upload two signature images using the form on the homepage.
+Click on Submit to compare the signatures.
+The system will display a message indicating whether the signatures are likely from the same person or not.
diff --git a/Signature Verification/app.py b/Signature Verification/app.py
@@ -0,0 +1,68 @@
+from flask import Flask, render_template, request
+import cv2
+import numpy as np
+import os
+
+app = Flask(__name__)
+app.config['UPLOAD_FOLDER'] = 'uploads/'
+os.makedirs(app.config['UPLOAD_FOLDER'], exist_ok=True)
+
+def preprocess_signature(image_path):
+    # Read the image
+    image = cv2.imread(image_path)
+    # Convert to grayscale
+    gray_image = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
+    # Resize the image to a standard size
+    resized_image = cv2.resize(gray_image, (128, 128))
+    # Threshold the image (binary)
+    _, binary_image = cv2.threshold(resized_image, 128, 255, cv2.THRESH_BINARY_INV)
+    return binary_image
+
+def compute_histogram(image):
+    # Compute the histogram (256 bins for grayscale image)
+    hist = cv2.calcHist([image], [0], None, [256], [0, 256])
+    # Normalize the histogram
+    hist = cv2.normalize(hist, hist).flatten()
+    return hist
+
+def compare_signatures(signature1, signature2):
+    # Compute histograms for both signatures
+    hist1 = compute_histogram(signature1)
+    hist2 = compute_histogram(signature2)
+    # Compare histograms using correlation method
+    score = cv2.compareHist(hist1, hist2, cv2.HISTCMP_CORREL)
+    return score
+
+@app.route('/')
+def index():
+    return render_template('index.html')
+
+@app.route('/compare', methods=['POST'])
+def compare():
+    if 'signature1' not in request.files or 'signature2' not in request.files:
+        return "No files uploaded", 400
+
+    file1 = request.files['signature1']
+    file2 = request.files['signature2']
+
+    path1 = os.path.join(app.config['UPLOAD_FOLDER'], file1.filename)
+    path2 = os.path.join(app.config['UPLOAD_FOLDER'], file2.filename)
+
+    file1.save(path1)
+    file2.save(path2)
+
+    # Process the signatures
+    sig1 = preprocess_signature(path1)
+    sig2 = preprocess_signature(path2)
+
+    # Compare signatures
+    similarity_score = compare_signatures(sig1, sig2)
+
+    # Set a threshold for verification
+    threshold = 0.7
+    result = "<b>The signatures matched successfully.</b>" if similarity_score > threshold else "<b>The signatures are likely to be different.</b>"
+
+    return result
+
+if __name__ == '__main__':
+    app.run(debug=True)
diff --git a/Signature Verification/methods.html b/Signature Verification/methods.html
@@ -0,0 +1,65 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Methods - Signature Verification</title>
+    <link rel="stylesheet" href="{{ url_for('static', filename='style.css') }}">
+</head>
+<body>
+
+    <header>
+        <h1>Signature Verification System</h1>
+        <nav>
+            <ul>
+                <li><a href="{{ url_for('index') }}">Home</a></li>
+                <li><a href="{{ url_for('methods') }}">Methods</a></li>
+                <li><a href="{{ url_for('compare') }}">Compare</a></li>
+            </ul>
+        </nav>
+    </header>
+
+    <main>
+        <section>
+            <h2>Methods Used in Signature Verification</h2>
+            <p>This Signature Verification System uses several steps to analyze and compare the signatures. Below are the main steps involved:</p>
+
+            <h3>1. Preprocessing the Signatures</h3>
+            <p>The first step is to preprocess the uploaded images. The following preprocessing techniques are applied:</p>
+            <ul>
+                <li><b>Grayscale Conversion:</b> The color images are converted into grayscale to reduce complexity.</li>
+                <li><b>Thresholding:</b> Thresholding is applied to the image to create a binary image that distinguishes the signature from the background.</li>
+                <li><b>Contour Detection:</b> Contours are detected in both the uploaded signatures using OpenCV to extract the structure of the signatures.</li>
+            </ul>
+
+            <h3>2. Comparing Signatures</h3>
+            <p>The core method of comparison involves calculating a similarity score between the two signatures:</p>
+            <ul>
+                <li><b>Histogram Comparison:</b> We use OpenCV’s <code>cv2.compareHist()</code> function to compare the histograms of the two signatures. This gives a score indicating the degree of similarity between the two images.</li>
+                <li><b>Correlation Method:</b> The correlation method is used to compute the similarity between the two histograms. A higher correlation score means the signatures are more similar.</li>
+            </ul>
+
+            <h3>3. Decision Making</h3>
+            <p>Once the similarity score is calculated, a threshold is applied to determine if the signatures match:</p>
+            <ul>
+                <li>If the similarity score is above the predefined threshold, the signatures are considered to be from the same person.</li>
+                <li>If the score is below the threshold, the signatures are likely different.</li>
+            </ul>
+        </section>
+
+        <section>
+            <h2>Technologies Used</h2>
+            <ul>
+                <li><b>Flask:</b> Flask is used to handle the backend logic and serve the web application.</li>
+                <li><b>OpenCV:</b> OpenCV is used for image processing and signature comparison.</li>
+                <li><b>Jinja2:</b> Flask’s templating engine Jinja2 is used to render dynamic HTML pages.</li>
+            </ul>
+        </section>
+    </main>
+
+    <footer>
+        <p>&copy; 2024 Signature Verification System. All rights reserved.</p>
+    </footer>
+
+</body>
+</html>
diff --git a/Signature Verification/results/Screenshot 2024-10-13 001054.png b/Signature Verification/results/Screenshot 2024-10-13 001054.png
diff --git a/Signature Verification/results/Screenshot 2024-10-13 001842.png b/Signature Verification/results/Screenshot 2024-10-13 001842.png
diff --git a/Signature Verification/results/Screenshot 2024-10-13 001923.png b/Signature Verification/results/Screenshot 2024-10-13 001923.png
diff --git a/Signature Verification/templates/index.html b/Signature Verification/templates/index.html
@@ -0,0 +1,73 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <!-- Required meta tags -->
+    <meta charset="utf-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1" />
+
+    <!-- Bootstrap CSS -->
+    <link
+      href="https://cdn.jsdelivr.net/npm/[email protected]/dist/css/bootstrap.min.css"
+      rel="stylesheet"
+      integrity="sha384-EVSTQN3/azprG1Anm3QDgpJLIm9Nao0Yz1ztcQTwFspd3yD65VohhpuuCOmLASjC"
+      crossorigin="anonymous"
+    />
+
+    <title>Signature Verification Tool</title>
+  </head>
+  <body>
+    <div class="container">
+      <nav class="navbar navbar-expand-lg navbar-dark bg-dark">
+        <div class="container-fluid">
+          <a class="navbar-brand" href="#">Dashboard</a>
+          <button
+            class="navbar-toggler"
+            type="button"
+            data-bs-toggle="collapse"
+            data-bs-target="#navbarSupportedContent"
+            aria-controls="navbarSupportedContent"
+            aria-expanded="false"
+            aria-label="Toggle navigation"
+          >
+            <span class="navbar-toggler-icon"></span>
+          </button>
+        </div>
+      </nav>
+      <div class = "container my-3">
+      <form
+        id="uploadForm"
+        action="/compare"
+        method="post"
+        enctype="multipart/form-data"
+      >
+        <div class="mb-3">
+          <label for="signature1" class="form-label">Upload signature 1</label>
+          <input
+            class="form-control"
+            type="file"
+            name="signature1"
+            accept="image/*"
+            required
+          />
+        </div>
+        <div class="mb-3">
+          <label for="signature2" class="form-label">Upload signature 2</label>
+          <input
+            class="form-control"
+            type="file"
+            name="signature2"
+            accept="image/*"
+            required
+          />
+        </div>
+        <button type="submit" class="btn btn-outline-success">Verify</button>
+      </form>
+    </div>
+    </div>
+    <script
+      src="https://cdn.jsdelivr.net/npm/[email protected]/dist/js/bootstrap.bundle.min.js"
+      integrity="sha384-MrcW6ZMFYlzcLA8Nl+NtUVF0sA7MsXsP1UyJoMp4YLEuNSfAP+JcXn/tWtIaxVXM"
+      crossorigin="anonymous"
+    ></script>
+  </body>
+</html>
diff --git a/Signature Verification/uploads/my sign_page-0001-min.jpg b/Signature Verification/uploads/my sign_page-0001-min.jpg
diff --git a/Signature Verification/uploads/my sign_page-0001.jpg b/Signature Verification/uploads/my sign_page-0001.jpg