gradients_and_edge_detection.ipynb

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 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Gradients and Edge Detection"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Gradients of an Image"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "import numpy as np\n",
    "import cv2"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [],
   "source": [
    "image = cv2.imread('sample_image.jpg')\n",
    "cv2.imshow(\"Original\", image)\n",
    "cv2.waitKey(0)\n",
    "cv2.destroyAllWindows()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [],
   "source": [
    "gray_image = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)\n",
    "cv2.imshow(\"Grayscaled Image\", gray_image)\n",
    "cv2.waitKey(0)\n",
    "cv2.destroyAllWindows()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Laplacian Gradient"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [],
   "source": [
    "lap_gradient = cv2.Laplacian(gray_image, cv2.CV_64F)\n",
    "lap_gradient = np.uint8(np.absolute(lap_gradient))\n",
    "cv2.imshow(\"Laplacian Gradient\", lap_gradient)\n",
    "cv2.waitKey(0)\n",
    "cv2.destroyAllWindows()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Sobel Gradient"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [],
   "source": [
    "sobelX = cv2.Sobel(gray_image, cv2.CV_64F, 1, 0) # For Vertical Edge Features\n",
    "sobelY = cv2.Sobel(gray_image, cv2.CV_64F, 0, 1) # For Horizontal Edge Features\n",
    "sobelX = np.uint8(np.absolute(sobelX))\n",
    "sobelY = np.uint8(np.absolute(sobelY))\n",
    "sobelCombined = cv2.bitwise_or(sobelX, sobelY)\n",
    "cv2.imshow(\"SobelX Gradient\", sobelX)\n",
    "cv2.imshow(\"SobelY Gradient\", sobelY)\n",
    "cv2.imshow(\"Sobel Combined Gradient\", sobelCombined)\n",
    "cv2.waitKey(0)\n",
    "cv2.destroyAllWindows()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Canny Edge Detection"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [],
   "source": [
    "blurred_image = cv2.GaussianBlur(gray_image, (5, 5), 0)\n",
    "cv2.imshow(\"Blurred Image\", blurred_image)\n",
    "\n",
    "canny_edge_image = cv2.Canny(blurred_image, 30, 150)\n",
    "cv2.imshow(\"Canny Edge Detection\", canny_edge_image)\n",
    "\n",
    "cv2.waitKey(0)\n",
    "cv2.destroyAllWindows()"
   ]
  }
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