open_cv_fundamentals.ipynb

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   "source": [
    "## Reading, Writing and Displaying images with opencv\n",
    "\n",
    "   - Lets start by importing opencv library"
   ]
  },
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   "cell_type": "code",
   "execution_count": 1,
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     "text": [
      "Requirement already satisfied: opencv-contrib-python in ./anaconda3/lib/python3.7/site-packages (4.1.0.25)\n",
      "Requirement already satisfied: numpy>=1.14.5 in ./anaconda3/lib/python3.7/site-packages (from opencv-contrib-python) (1.16.2)\n",
      "Note: you may need to restart the kernel to use updated packages.\n"
     ]
    }
   ],
   "source": [
    "pip install opencv-contrib-python"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [],
   "source": [
    "import cv2\n",
    "import numpy as np"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "- Let's now load our first image"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [],
   "source": [
    "\n",
    "#Load an image using imread specifying the path to image\n",
    "\n",
    "input = cv2.imread('/home/anonymous_pk7/anaconda3/images/elephant.jpeg')\n",
    "\n",
    "#Our file 'input.jpg' is now loaded and stored in python\n",
    "# as a variable we named 'image'\n",
    "\n",
    "# To display our image variable, we use 'imshow'\n",
    "# The first parameter will be title shown on imaage window\n",
    "# The second parameter is the image variable\n",
    "\n",
    "cv2.imshow('Test Elephant Image',input)\n",
    "\n",
    "# 'waitkey' allows us to input information when a image window is open\n",
    "# By leaving it blank it just waits for anykey to be pressed before\n",
    "# continuing, By placing numbers (except 0), we can specify a delay for\n",
    "# how long you keep the window open(time is in milliseconds here)\n",
    "\n",
    "cv2.waitKey(7000)\n",
    "\n",
    "# This closes all open windows\n",
    "# Failure to palce this will cause your program to hang\n",
    "\n",
    "cv2.destroyAllWindows()\n"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Let's take a closer look at how images are stored"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "(351, 500, 3)\n"
     ]
    }
   ],
   "source": [
    "print(input.shape)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Let us  print each dimension of image"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Height of Image:  351  pixels\n",
      "Width of Image:  500  pixels\n"
     ]
    }
   ],
   "source": [
    "print('Height of Image: ',int(input.shape[0]),' pixels')\n",
    "print('Width of Image: ',int(input.shape[1]),' pixels')"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### How do we save images we edit in Opencv"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 6,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Simply write 'imwrite' specifying the file name and the image to be saved\n",
    "\n",
    "cv2.imwrite('output.jpg',input)\n",
    "cv2.imwrite('output.png',input)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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