Lecture 3.8 - Bitwise Operations and Masking.ipynb

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    "## Bitwise Operations and Masking\n",
    "\n",
    "To demonstrate these operations let's create some simple images"
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    "import cv2\n",
    "import numpy as np\n",
    "\n",
    "# If you're wondering why only two dimensions, well this is a grayscale image, \n",
    "# if we doing a colored image, we'd use \n",
    "# rectangle = np.zeros((300, 300, 3),np.uint8)\n",
    "\n",
    "#making a square\n",
    "\n",
    "square = np.zeros((300,300), np.uint8)\n",
    "cv2.rectangle(square, (50,50), (250,250), 255,-1)\n",
    "cv2.imshow('square', square)\n",
    "\n",
    "ellipse = np.zeros((300,300),np.uint8)\n",
    "cv2.ellipse(ellipse, (150,150), (150,150), 30,0,120,255,-1)\n",
    "cv2.imshow('ellpise', ellipse)\n",
    "cv2.waitKey(0)\n",
    "cv2.destroyAllWindows()"
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    "### Experimenting with some bitwise operations"
   ]
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   "execution_count": 19,
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   "source": [
    "# Shows only where they intersect\n",
    "And = cv2.bitwise_and(square, ellipse)\n",
    "cv2.imshow(\"AND\", And)\n",
    "cv2.waitKey(0)\n",
    "\n",
    "# Shows where either square or ellipse is \n",
    "bitwiseOr = cv2.bitwise_or(square, ellipse)\n",
    "cv2.imshow(\"OR\", bitwiseOr)\n",
    "cv2.waitKey(0) \n",
    "\n",
    "# Shows where either exist by itself\n",
    "bitwiseXor = cv2.bitwise_xor(square, ellipse)\n",
    "cv2.imshow(\"XOR\", bitwiseXor)\n",
    "cv2.waitKey(0)\n",
    "\n",
    "# Shows everything that isn't part of the square\n",
    "bitwiseNot_sq = cv2.bitwise_not(square)\n",
    "cv2.imshow(\"NOT - square\", bitwiseNot_sq)\n",
    "cv2.waitKey(0)\n",
    "\n",
    "bitwiseNot_el = cv2.bitwise_not(ellipse)\n",
    "cv2.imshow(\"NOT - ellipse\", bitwiseNot_el)\n",
    "cv2.waitKey(0)\n",
    "### Notice the last operation inverts the image totally\n",
    "\n",
    "cv2.destroyAllWindows()"
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    "\n",
    "\n",
    "\n",
    "\n",
    "\n"
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