geometric_transformations.ipynb

{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Performing Geometric Transformations on an Image"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "import cv2\n",
    "import numpy as np"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [],
   "source": [
    "img = cv2.imread(\"sample_image.jpg\")\n",
    "cv2.imshow(\"Original\", img)\n",
    "cv2.waitKey(0)\n",
    "cv2.destroyAllWindows()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Image Translation"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [],
   "source": [
    "def translate(image, x, y):\n",
    "    M = np.float32([[1, 0, x], [0, 1, y]])\n",
    "    shifted = cv2.warpAffine(image, M, (image.shape[1], image.shape[0]))\n",
    "    return shifted\n",
    "\n",
    "shifted = translate(img, x=70, y=-50)\n",
    "cv2.imshow(\"Shifted\", shifted)\n",
    "cv2.waitKey(0)\n",
    "cv2.destroyAllWindows()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Image Rotation"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [],
   "source": [
    "def rotate(image, angle, center=None, scale=1.0):\n",
    "    (h, w) = image.shape[:2]\n",
    "    \n",
    "    if center is None:\n",
    "        center = (w//2, h//2)\n",
    "        \n",
    "    M = cv2.getRotationMatrix2D(center, angle, scale)\n",
    "    rotate = cv2.warpAffine(image, M, (w, h))\n",
    "    return rotate\n",
    "\n",
    "rotated = rotate(img, 60, scale=0.2)\n",
    "cv2.imshow(\"Rotated\", rotated)\n",
    "cv2.waitKey(0)\n",
    "cv2.destroyAllWindows()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Image Resizing (Maintaining Aspect Ratio)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [],
   "source": [
    "def resize(image, width=None, height=None, inter=cv2.INTER_AREA):\n",
    "    dim=None\n",
    "    (h, w) = image.shape[:2]\n",
    "    \n",
    "    if width is None and height is None:\n",
    "        return image\n",
    "    \n",
    "    if width is None:\n",
    "        r = height/float(h)\n",
    "        dim = (int(w*r), height)\n",
    "        \n",
    "    else:\n",
    "        r = width/float(w)\n",
    "        dim = (width, int(h*r))\n",
    "        \n",
    "    resized = cv2.resize(image, dim, interpolation=inter)\n",
    "    return resized\n",
    "\n",
    "resized = resize(img, height=400)\n",
    "cv2.imshow(\"Resized(Height)\", resized)\n",
    "cv2.waitKey(0)\n",
    "cv2.destroyAllWindows()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Image Flipping"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [],
   "source": [
    "flipped_horizontally = cv2.flip(img, 1)\n",
    "flipped_vertically = cv2.flip(img, 0)\n",
    "flipped_horizontally_vertically = cv2.flip(img, -1)\n",
    "\n",
    "cv2.imshow(\"Flipped Horizontally\", flipped_horizontally)\n",
    "cv2.imshow(\"Flipped Vertically\", flipped_vertically)\n",
    "cv2.imshow(\"Flipped Horizontally & Vertically\", flipped_horizontally_vertically)\n",
    "cv2.waitKey(0)\n",
    "cv2.destroyAllWindows()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Image Cropping"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [],
   "source": [
    "cropped = img[500:1400, 100:1800]\n",
    "cv2.imshow(\"Cropped Image\", cropped)\n",
    "\n",
    "cv2.waitKey(0)\n",
    "cv2.destroyAllWindows()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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