extract line and plot

read_grayscale_image.ipynb

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    "language_info": {
      "name": "python"
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  "cells": [
    {
      "cell_type": "code",
      "source": [
        "!wget https://upload.wikimedia.org/wikipedia/commons/f/fa/Grayscale_8bits_palette_sample_image.png"
      ],
      "metadata": {
        "id": "TQwyJ7Wbps1b"
      },
      "execution_count": null,
      "outputs": []
    },
    {
      "cell_type": "code",
      "source": [
        "import cv2\n",
        "import numpy as np\n",
        "from matplotlib import pyplot as plt\n",
        "\n",
        "# Load the image in grayscale\n",
        "img = cv2.imread('Grayscale_8bits_palette_sample_image.png')\n",
        "plt.imshow(img)"
      ],
      "metadata": {
        "id": "_5PsleQgpgoz"
      },
      "execution_count": null,
      "outputs": []
    },
    {
      "cell_type": "code",
      "source": [
        "# Extract a line of pixels (from (0, 10) to (0, 60))\n",
        "line_pixels = img[50, 10:60]\n",
        "\n",
        "plt.figure(figsize=(10, 4))\n",
        "plt.plot(line_pixels, marker='o')\n",
        "plt.title('Pixel Intensities')\n",
        "plt.xlabel('Pixel Position')\n",
        "plt.ylabel('Intensity')\n",
        "plt.grid(True)\n",
        "plt.show()\n",
        "\n",
        "img_highlighted = img.copy()\n",
        "img_highlighted[50, 10:60] = 255\n",
        "\n",
        "plt.figure(figsize=(6, 6))\n",
        "plt.imshow(img_highlighted, cmap='gray')\n",
        "plt.title('Image with Highlighted Line')\n",
        "plt.axis('off')\n",
        "plt.show()\n",
        "\n"
      ],
      "metadata": {
        "id": "aZIAwLDBpqgU"
      },
      "execution_count": null,
      "outputs": []
    },
    {
      "cell_type": "code",
      "source": [],
      "metadata": {
        "id": "SVPJ1IIFsNlx"
      },
      "execution_count": null,
      "outputs": []
    }
  ]
}