notebooks/composite/closest_date.ipynb

{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Composite \"Closest Date\"\n",
    "Takes the last image of the given collection and fills the masked pixels with the last available pixel"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "import ee\n",
    "ee.Initialize()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [],
   "source": [
    "from geetools import tools, composite, cloud_mask, algorithms"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [],
   "source": [
    "import geedatasets\n",
    "import ipygee as ui"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "data": {
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       "model_id": "da7561a8e7f54c18b1a08f1b44557a4a",
       "version_major": 2,
       "version_minor": 0
      },
      "text/plain": [
       "Map(center=[0, 0], controls=(ZoomControl(options=['position', 'zoom_in_text', 'zoom_in_title', 'zoom_out_text'…"
      ]
     },
     "metadata": {},
     "output_type": "display_data"
    },
    {
     "data": {
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       "model_id": "573e88a2517c4f6695eb8291927f10e1",
       "version_major": 2,
       "version_minor": 0
      },
      "text/plain": [
       "Tab(children=(CustomInspector(children=(SelectMultiple(options=OrderedDict(), value=()), Accordion(selected_in…"
      ]
     },
     "metadata": {},
     "output_type": "display_data"
    }
   ],
   "source": [
    "Map = ui.Map()\n",
    "Map.show()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [],
   "source": [
    "l8 = geedatasets.landsat.Landsat8SR()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [],
   "source": [
    "vis = l8.visualization('NSR')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [],
   "source": [
    "l8col = l8.collection()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [],
   "source": [
    "p = ee.Geometry.Point([-70.72, -41.92]).buffer(50000)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [],
   "source": [
    "Map.addLayer(p)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 12,
   "metadata": {},
   "outputs": [],
   "source": [
    "Map.centerObject(p, zoom=8)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### add date band"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {},
   "outputs": [],
   "source": [
    "col = l8col.map(lambda img: img.addBands(tools.date.makeDateBand(img)))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Filter and mask clouds"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [],
   "source": [
    "col = col.filterBounds(p)\\\n",
    "         .filterDate('2017-01-01', '2017-03-01')\\\n",
    "         .map(lambda img: l8.applyMask(img, 'pixel_qa', ['cloud', 'shadow', 'snow']))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "application/vnd.jupyter.widget-view+json": {
       "model_id": "acef348bfdac408286e6891f46efa5b7",
       "version_major": 2,
       "version_minor": 0
      },
      "text/plain": [
       "VBox(children=(Accordion(children=(Button(description='Cancel', style=ButtonStyle()),), _titles={'0': 'Loading…"
      ]
     },
     "metadata": {},
     "output_type": "display_data"
    }
   ],
   "source": [
    "ui.eprint(col.size())"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### add all images to the map"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 16,
   "metadata": {},
   "outputs": [],
   "source": [
    "Map.addImageCollection(col, vis, '{system_date} {id}')"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Make composite"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 17,
   "metadata": {},
   "outputs": [],
   "source": [
    "comp = composite.closestDate(col)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "metadata": {},
   "outputs": [],
   "source": [
    "Map.addLayer(comp, vis, 'composite')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {},
   "outputs": [],
   "source": [
    "Map.addLayer(comp.select('date').randomVisualizer(), {'bands':['viz-red', 'viz-green', 'viz-blue'], 'min':0, 'max':255}, 'dates')"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### clip to first image (target date)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 20,
   "metadata": {},
   "outputs": [],
   "source": [
    "comp_clip = composite.closestDate(col, clip_to_first=True)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 21,
   "metadata": {},
   "outputs": [],
   "source": [
    "Map.addLayer(comp_clip, vis, 'composite 2017-02-25 clip to first')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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