Visualization/image_stretch.ipynb

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        "<table class=\"ee-notebook-buttons\" align=\"left\">\n",
        "    <td><a target=\"_blank\"  href=\"https://github.com/giswqs/earthengine-py-notebooks/tree/master/Visualization/image_stretch.ipynb\"><img width=32px src=\"https://www.tensorflow.org/images/GitHub-Mark-32px.png\" /> View source on GitHub</a></td>\n",
        "    <td><a target=\"_blank\"  href=\"https://nbviewer.jupyter.org/github/giswqs/earthengine-py-notebooks/blob/master/Visualization/image_stretch.ipynb\"><img width=26px src=\"https://upload.wikimedia.org/wikipedia/commons/thumb/3/38/Jupyter_logo.svg/883px-Jupyter_logo.svg.png\" />Notebook Viewer</a></td>\n",
        "    <td><a target=\"_blank\"  href=\"https://colab.research.google.com/github/giswqs/earthengine-py-notebooks/blob/master/Visualization/image_stretch.ipynb\"><img src=\"https://www.tensorflow.org/images/colab_logo_32px.png\" /> Run in Google Colab</a></td>\n",
        "</table>"
      ]
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    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "## Install Earth Engine API and geemap\n",
        "Install the [Earth Engine Python API](https://developers.google.com/earth-engine/python_install) and [geemap](https://geemap.org). The **geemap** Python package is built upon the [ipyleaflet](https://github.com/jupyter-widgets/ipyleaflet) and [folium](https://github.com/python-visualization/folium) packages and implements several methods for interacting with Earth Engine data layers, such as `Map.addLayer()`, `Map.setCenter()`, and `Map.centerObject()`.\n",
        "The following script checks if the geemap package has been installed. If not, it will install geemap, which automatically installs its [dependencies](https://github.com/giswqs/geemap#dependencies), including earthengine-api, folium, and ipyleaflet."
      ]
    },
    {
      "cell_type": "code",
      "metadata": {},
      "source": [
        "# Installs geemap package\n",
        "import subprocess\n",
        "\n",
        "try:\n",
        "    import geemap\n",
        "except ImportError:\n",
        "    print('Installing geemap ...')\n",
        "    subprocess.check_call([\"python\", '-m', 'pip', 'install', 'geemap'])"
      ],
      "outputs": [],
      "execution_count": null
    },
    {
      "cell_type": "code",
      "metadata": {},
      "source": [
        "import ee\n",
        "import geemap"
      ],
      "outputs": [],
      "execution_count": null
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "## Create an interactive map \n",
        "The default basemap is `Google Maps`. [Additional basemaps](https://github.com/giswqs/geemap/blob/master/geemap/basemaps.py) can be added using the `Map.add_basemap()` function. "
      ]
    },
    {
      "cell_type": "code",
      "metadata": {},
      "source": [
        "Map = geemap.Map(center=[40,-100], zoom=4)\n",
        "Map"
      ],
      "outputs": [],
      "execution_count": null
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "## Add Earth Engine Python script "
      ]
    },
    {
      "cell_type": "code",
      "metadata": {},
      "source": [
        "# Add Earth Engine dataset\n",
        "# Load a Landsat 8 raw image.\n",
        "image = ee.Image('LANDSAT/LC08/C01/T1/LC08_044034_20140318')\n",
        "\n",
        "# Define a RasterSymbolizer element with '_enhance_' for a placeholder.\n",
        "template_sld = \\\n",
        "  '<RasterSymbolizer>' + \\\n",
        "    '<ContrastEnhancement><_enhance_/></ContrastEnhancement>' + \\\n",
        "    '<ChannelSelection>' + \\\n",
        "      '<RedChannel>' + \\\n",
        "        '<SourceChannelName>B5</SourceChannelName>' + \\\n",
        "      '</RedChannel>' + \\\n",
        "      '<GreenChannel>' + \\\n",
        "        '<SourceChannelName>B4</SourceChannelName>' + \\\n",
        "      '</GreenChannel>' + \\\n",
        "      '<BlueChannel>' + \\\n",
        "        '<SourceChannelName>B3</SourceChannelName>' + \\\n",
        "      '</BlueChannel>' + \\\n",
        "    '</ChannelSelection>' + \\\n",
        "  '</RasterSymbolizer>'\n",
        "\n",
        "# Get SLDs with different enhancements.\n",
        "equalize_sld = template_sld.replace('_enhance_', 'Histogram')\n",
        "normalize_sld = template_sld.replace('_enhance_', 'Normalize')\n",
        "\n",
        "# Display the results.\n",
        "Map.centerObject(image, 10)\n",
        "Map.addLayer(image, {'bands': ['B5', 'B4', 'B3'], 'min': 0, 'max': 15000}, 'Linear')\n",
        "Map.addLayer(image.sldStyle(equalize_sld), {}, 'Equalized')\n",
        "Map.addLayer(image.sldStyle(normalize_sld), {}, 'Normalized')"
      ],
      "outputs": [],
      "execution_count": null
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "## Display Earth Engine data layers "
      ]
    },
    {
      "cell_type": "code",
      "metadata": {},
      "source": [
        "Map.addLayerControl() # This line is not needed for ipyleaflet-based Map.\n",
        "Map"
      ],
      "outputs": [],
      "execution_count": null
    }
  ],
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