import os
from datetime import datetime
import ee
import json
import geemap
import numpy as np
import geemap.foliumap as gee_folium
import leafmap.foliumap as leaf_folium
import streamlit as st
import pandas as pd
import geopandas as gpd
from shapely.ops import transform
from functools import reduce
import plotly.express as px
import branca.colormap as cm
st.set_page_config(layout="wide")
m = st.markdown(
"""
""",
unsafe_allow_html=True,
)
# Logo
cols = st.columns([1, 7, 1])
with cols[0]:
st.image("Final_IITGN-Logo-symmetric-Color.png")
with cols[-1]:
st.image("IFS.jpg")
# Title
# make title in center
with cols[1]:
st.markdown(
f"""
Vrinda (वृन्दा): Interactive Vegetation Index Analyzer
""",
unsafe_allow_html=True,
)
############################################
# Hyperparameters
############################################
st.write("User Inputs
", unsafe_allow_html=True)
st.write("Select the vegetation indices to calculate:")
all_veg_indices = ["NDVI", "EVI", "EVI2"]
formulas = {
"NDVI": r"$\frac{NIR - Red}{NIR + Red}$",
"EVI": r"$G \times \frac{NIR - Red}{NIR + C1 \times Red - C2 \times Blue + L}$",
"EVI2": r"$G \times \frac{NIR - Red}{NIR + L + C \times Red}$",
}
defaults = [True, False, False]
veg_indices = []
for veg_index, default in zip(all_veg_indices, defaults):
if st.checkbox(f"{veg_index} = {formulas[veg_index]}", value=default):
veg_indices.append(veg_index)
with st.expander("EVI/EVI2 Parameters"):
st.write("Select the parameters for the EVI/EVI2 calculation (default is as per EVI's Wikipedia page)")
cols = st.columns(5)
evi_vars = {}
for col, name, default in zip(cols, ["G", "C1", "C2", "L", "C"], [2.5, 6, 7.5, 1, 2.4]):
value = col.number_input(f"{name}", value=default)
evi_vars[name] = value
############################################
# Functions
############################################
def daterange_str_to_dates(daterange_str):
start_date, end_date = daterange_str.split("-")
start_date = pd.to_datetime(start_date)
end_date = pd.to_datetime(end_date)
return start_date, end_date
def daterange_dates_to_str(start_date, end_date):
return f"{start_date.strftime('%Y/%m/%d')}-{end_date.strftime('%Y/%m/%d')}"
def daterange_str_to_year(daterange_str):
start_date, _ = daterange_str.split("-")
year = pd.to_datetime(start_date).year
return year
def shape_3d_to_2d(shape):
if shape.has_z:
return transform(lambda x, y, z: (x, y), shape)
else:
return shape
def preprocess_gdf(gdf):
gdf = gdf.to_crs(epsg=7761) # epsg for Gujarat
gdf["geometry"] = gdf["geometry"].apply(shape_3d_to_2d)
return gdf
def check_valid_geometry(geometry_gdf):
geometry = geometry_gdf.geometry.item()
if geometry.type != "Polygon":
st.error(f"Selected geometry is of type '{geometry.type}'. Please provide a 'Polygon' geometry.")
st.stop()
def add_geometry_to_maps(map_list, opacity=0.0):
for m in map_list:
m.add_gdf(
buffer_geometry_gdf,
layer_name="Geometry Buffer",
style_function=lambda x: {"color": "red", "fillOpacity": opacity, "fillColor": "red"},
)
m.add_gdf(
geometry_gdf,
layer_name="Geometry",
style_function=lambda x: {"color": "blue", "fillOpacity": opacity, "fillColor": "blue"},
)
def get_dem_slope_maps(buffer_ee_geometry):
# Create the map for DEM
dem_map = gee_folium.Map()
dem_map.add_tile_layer(
wayback_mapping[latest_date], name=f"Esri Wayback - {latest_date.replace('-', '/')}", attribution="Esri"
)
dem_layer = ee.Image("USGS/SRTMGL1_003")
# Set the target resolution to 10 meters
target_resolution = 10
dem_layer = (
dem_layer.resample("bilinear").reproject(crs="EPSG:4326", scale=target_resolution).clip(buffer_ee_geometry)
)
# Generate contour lines using elevation thresholds
terrain = ee.Algorithms.Terrain(dem_layer)
contour_interval = 1
contours = (
terrain.select("elevation").subtract(terrain.select("elevation").mod(contour_interval)).rename("contours")
)
# Calculate the minimum and maximum values
stats = contours.reduceRegion(reducer=ee.Reducer.minMax(), scale=30, maxPixels=1e13)
max_value = stats.get("contours_max").getInfo()
min_value = stats.get("contours_min").getInfo()
vis_params = {"min": min_value, "max": max_value, "palette": ["blue", "green", "yellow", "red"]}
dem_map.addLayer(contours, vis_params, "Contours")
# Create a colormap
colormap = cm.LinearColormap(colors=vis_params["palette"], vmin=vis_params["min"], vmax=vis_params["max"])
dem_map.add_child(colormap)
# Create the map for Slope
slope_map = gee_folium.Map()
slope_map.add_tile_layer(
wayback_mapping[latest_date], name=f"Esri Wayback - {latest_date.replace('-', '/')}", attribution="Esri"
)
# Calculate slope from the DEM
slope_layer = (
ee.Terrain.slope(
ee.Image("USGS/SRTMGL1_003").resample("bilinear").reproject(crs="EPSG:4326", scale=target_resolution)
)
.clip(buffer_ee_geometry)
.rename("slope")
)
# Calculate the minimum and maximum values
stats = slope_layer.reduceRegion(reducer=ee.Reducer.minMax(), scale=30, maxPixels=1e13)
max_value = stats.get("slope_max").getInfo()
min_value = stats.get("slope_min").getInfo()
vis_params = {"min": min_value, "max": max_value, "palette": ["blue", "green", "yellow", "red"]}
slope_map.addLayer(slope_layer, vis_params, "Slope Layer")
# Create a colormap
colormap = cm.LinearColormap(colors=vis_params["palette"], vmin=vis_params["min"], vmax=vis_params["max"])
slope_map.add_child(colormap)
return dem_map, slope_map
def add_indices(image, nir_band, red_band, blue_band):
# Add negative cloud
neg_cloud = image.select("MSK_CLDPRB").multiply(-1).rename("Neg_MSK_CLDPRB")
nir = image.select(nir_band).divide(10000)
red = image.select(red_band).divide(10000)
blue = image.select(blue_band).divide(10000)
numerator = nir.subtract(red)
ndvi = (numerator).divide(nir.add(red)).rename("NDVI").clamp(-1, 1)
# EVI formula taken from: https://en.wikipedia.org/wiki/Enhanced_vegetation_index
denominator = nir.add(red.multiply(evi_vars["C1"])).subtract(blue.multiply(evi_vars["C2"])).add(evi_vars["L"])
evi = numerator.divide(denominator).multiply(evi_vars["G"]).rename("EVI").clamp(-1, 1)
evi2 = (
numerator.divide(nir.add(evi_vars["L"]).add(red.multiply(evi_vars["C"])))
.multiply(evi_vars["G"])
.rename("EVI2")
.clamp(-1, 1)
)
return image.addBands([neg_cloud, ndvi, evi, evi2])
def process_date(daterange, satellite, veg_indices):
start_date, end_date = daterange
daterange_str = daterange_dates_to_str(start_date, end_date)
prefix = f"Processing {satellite} - {daterange_str}"
try:
attrs = satellites[satellite]
collection = attrs["collection"]
collection = collection.filterBounds(buffer_ee_geometry)
collection = collection.filterDate(start_date, end_date)
bucket = {}
for veg_index in veg_indices:
mosaic_veg_index = collection.qualityMosaic(veg_index)
fc = geemap.zonal_stats(
mosaic_veg_index, ee_feature_collection, scale=attrs["scale"], return_fc=True
).getInfo()
mean_veg_index = fc["features"][0]["properties"][veg_index]
bucket[veg_index] = mean_veg_index
fc = geemap.zonal_stats(
mosaic_veg_index, buffer_ee_feature_collection, scale=attrs["scale"], return_fc=True
).getInfo()
buffer_mean_veg_index = fc["features"][0]["properties"][veg_index]
bucket[f"{veg_index}_buffer"] = buffer_mean_veg_index
bucket[f"{veg_index}_ratio"] = mean_veg_index / buffer_mean_veg_index
bucket[f"mosaic_{veg_index}"] = mosaic_veg_index
# Get median mosaic
bucket["mosaic_visual_max_ndvi"] = collection.qualityMosaic("NDVI")
bucket["mosaic_visual_median"] = collection.median()
bucket["image_visual_least_cloud"] = collection.sort("CLOUDY_PIXEL_PERCENTAGE").first()
if satellite == "COPERNICUS/S2_SR_HARMONIZED":
cloud_mask_probability = fc["features"][0]["properties"]["MSK_CLDPRB"] / 100
else:
cloud_mask_probability = None
bucket["Cloud (0 to 1)"] = cloud_mask_probability
result_df.loc[daterange_str, list(bucket.keys())] = list(bucket.values())
count = collection.size().getInfo()
suffix = f" - Processed {count} images"
write_info(f"{prefix}{suffix}")
except Exception as e:
print(e)
suffix = f" - Imagery not available"
write_info(f"{prefix}{suffix}")
def write_info(info):
st.write(f"{info}", unsafe_allow_html=True)
############################################
# One time setup
############################################
def one_time_setup():
credentials_path = os.path.expanduser("~/.config/earthengine/credentials")
if os.path.exists(credentials_path):
pass # Earth Engine credentials already exist
elif "EE" in os.environ: # write the credentials to the file
ee_credentials = os.environ.get("EE")
os.makedirs(os.path.dirname(credentials_path), exist_ok=True)
with open(credentials_path, "w") as f:
f.write(ee_credentials)
else:
raise ValueError(
f"Earth Engine credentials not found at {credentials_path} or in the environment variable 'EE'"
)
ee.Initialize()
satellites = {
"COPERNICUS/S2_SR_HARMONIZED": {
"scale": 10,
"collection": ee.ImageCollection("COPERNICUS/S2_SR_HARMONIZED")
.select(
["B2", "B4", "B8", "MSK_CLDPRB", "TCI_R", "TCI_G", "TCI_B"],
["Blue", "Red", "NIR", "MSK_CLDPRB", "R", "G", "B"],
)
.map(lambda image: add_indices(image, nir_band="NIR", red_band="Red", blue_band="Blue")),
},
}
st.session_state.satellites = satellites
with open("wayback_imagery.json") as f:
st.session_state.wayback_mapping = json.load(f)
if "one_time_setup_done" not in st.session_state:
one_time_setup()
st.session_state.one_time_setup_done = True
satellites = st.session_state.satellites
wayback_mapping = st.session_state.wayback_mapping
############################################
# App
############################################
# Input: Satellite Sources
st.write("Select the satellite sources:")
satellite_selected = {}
for satellite in satellites:
satellite_selected[satellite] = st.checkbox(satellite, value=True, disabled=True)
# Date range input
max_year = datetime.now().year
jan_1 = pd.to_datetime(f"{max_year}/01/01", format="%Y/%m/%d")
dec_31 = pd.to_datetime(f"{max_year}/12/31", format="%Y/%m/%d")
nov_15 = pd.to_datetime(f"{max_year}/11/15", format="%Y/%m/%d")
dec_15 = pd.to_datetime(f"{max_year}/12/15", format="%Y/%m/%d")
input_daterange = st.date_input(
"Date Range (Ignore year. App will compute indices for all possible years)", (nov_15, dec_15), jan_1, dec_31
)
min_year = int(st.number_input("Minimum Year", value=2019, min_value=2015, step=1))
max_year = int(st.number_input("Maximum Year", value=max_year, min_value=2015, step=1))
# Input: GeoJSON/KML file
file_url = st.query_params.get("file_url", None)
if file_url is None:
file_url = st.file_uploader("Upload KML/GeoJSON file", type=["geojson", "kml", "shp"])
if file_url is None:
st.stop()
if isinstance(file_url, str):
if file_url.startswith("https://drive.google.com/file/d/"):
ID = file_url.replace("https://drive.google.com/file/d/", "").split("/")[0]
file_url = f"https://drive.google.com/uc?id={ID}"
elif file_url.startswith("https://drive.google.com/open?id="):
ID = file_url.replace("https://drive.google.com/open?id=", "")
file_url = f"https://drive.google.com/uc?id={ID}"
buffer = st.number_input("Buffer (m)", value=50, min_value=0, step=1)
input_gdf = preprocess_gdf(gpd.read_file(file_url))
# Input: Geometry
def format_fn(x):
return input_gdf.drop(columns=["geometry"]).loc[x].to_dict()
input_geometry_idx = st.selectbox("Select the geometry", input_gdf.index, format_func=format_fn)
geometry_gdf = input_gdf[input_gdf.index == input_geometry_idx]
check_valid_geometry(geometry_gdf)
outer_geometry_gdf = geometry_gdf.copy()
outer_geometry_gdf["geometry"] = outer_geometry_gdf["geometry"].buffer(buffer)
buffer_geometry_gdf = (
outer_geometry_gdf.difference(geometry_gdf).reset_index().drop(columns="index")
) # reset index forces GeoSeries to GeoDataFrame
buffer_geometry_gdf["Name"] = "Buffer"
# Derived Inputs
ee_geometry = ee.Geometry(geometry_gdf.to_crs(4326).geometry.item().__geo_interface__)
ee_feature_collection = ee.FeatureCollection(ee_geometry)
buffer_ee_geometry = ee.Geometry(buffer_geometry_gdf.to_crs(4326).geometry.item().__geo_interface__)
buffer_ee_feature_collection = ee.FeatureCollection(buffer_ee_geometry)
outer_ee_geometry = ee.Geometry(outer_geometry_gdf.to_crs(4326).geometry.item().__geo_interface__)
outer_ee_feature_collection = ee.FeatureCollection(outer_ee_geometry)
# visualize the geometry
m = leaf_folium.Map()
keys = list(wayback_mapping.keys())
latest_date = sorted(keys, key=lambda x: pd.to_datetime(x))[-1]
m.add_tile_layer(
wayback_mapping[latest_date], name=f"Esri Wayback - {latest_date.replace('-', '/')}", attribution="Esri"
)
# m.add_layer(buffer_ee_feature_collection)
add_geometry_to_maps([m], opacity=0.3)
write_info(
f"""
Latest Esri Imagery - {latest_date.replace('-', '/')}
"""
)
m.to_streamlit()
# Generate stats
stats_df = pd.DataFrame(
{
"Area (m^2)": geometry_gdf.area.item(),
"Perimeter (m)": geometry_gdf.length.item(),
"Points": json.loads(geometry_gdf.to_crs(4326).to_json())["features"][0]["geometry"]["coordinates"],
}
)
st.write("Geometry Metrics
", unsafe_allow_html=True)
st.markdown(
f"""| Metric | Value |
| --- | --- |
| Area (m^2) | {stats_df['Area (m^2)'].item():.2f} m^2 = {stats_df['Area (m^2)'].item()/10000:.2f} ha |
| Perimeter (m) | {stats_df['Perimeter (m)'].item():.2f} m |
| Points | {stats_df['Points'][0]} |
"""
)
stats_csv = stats_df.to_csv(index=False)
st.download_button("Download Geometry Metrics", stats_csv, "geometry_metrics.csv", "text/csv", use_container_width=True)
# Submit
submit = st.button("Calculate Vegetation Indices", use_container_width=True)
st.write("Results
", unsafe_allow_html=True)
if submit:
if not any(satellite_selected.values()):
st.error("Please select at least one satellite source")
st.stop()
# Create range
start_day = input_daterange[0].day
start_month = input_daterange[0].month
end_day = input_daterange[1].day
end_month = input_daterange[1].month
dates = []
for year in range(min_year, max_year + 1):
start_date = pd.to_datetime(f"{year}-{start_month:02d}-{start_day:02d}")
end_date = pd.to_datetime(f"{year}-{end_month:02d}-{end_day:02d}")
dates.append((start_date, end_date))
result_df = pd.DataFrame()
for satellite, attrs in satellites.items():
if not satellite_selected[satellite]:
continue
with st.spinner(f"Processing {satellite} ..."):
progress_bar = st.progress(0)
for i, daterange in enumerate(dates):
process_date(daterange, satellite, veg_indices)
progress_bar.progress((i + 1) / len(dates))
st.session_state.result = result_df
print("Printing result...")
if "result" in st.session_state:
result_df = st.session_state.result
print(result_df.columns)
# drop rows with all NaN values
result_df = result_df.dropna(how="all")
# drop columns with all NaN values
result_df = result_df.dropna(axis=1, how="all")
print(result_df.columns)
print(result_df.head(2))
# df.reset_index(inplace=True)
# df.index = pd.to_datetime(df["index"], format="%Y-%m")
for column in result_df.columns:
result_df[column] = pd.to_numeric(result_df[column], errors="ignore")
df_numeric = result_df.select_dtypes(include=["float64"])
st.write(df_numeric)
df_numeric_csv = df_numeric.to_csv(index=True)
st.download_button(
"Download Time Series Data", df_numeric_csv, "vegetation_indices.csv", "text/csv", use_container_width=True
)
df_numeric.index = [daterange_str_to_year(daterange) for daterange in df_numeric.index]
for veg_index in veg_indices:
fig = px.line(df_numeric, y=[veg_index, f"{veg_index}_buffer"], markers=True)
fig.update_layout(xaxis=dict(tickvals=df_numeric.index, ticktext=df_numeric.index))
st.plotly_chart(fig)
st.write(
"Visual Comparison between Two Years
", unsafe_allow_html=True
)
cols = st.columns(2)
with cols[0]:
year_1 = st.selectbox("Year 1", result_df.index, index=0, format_func=lambda x: daterange_str_to_year(x))
with cols[1]:
year_2 = st.selectbox(
"Year 2", result_df.index, index=len(result_df.index) - 1, format_func=lambda x: daterange_str_to_year(x)
)
vis_params = {"min": 0, "max": 1, "palette": ["white", "green"]} # Example visualisation for Sentinel-2
# Create a colormap and name it as NDVI
colormap = cm.LinearColormap(colors=vis_params["palette"], vmin=vis_params["min"], vmax=vis_params["max"])
for veg_index in veg_indices:
st.write(f"{veg_index}
", unsafe_allow_html=True)
cols = st.columns(2)
for col, daterange_str in zip(cols, [year_1, year_2]):
mosaic = result_df.loc[daterange_str, f"mosaic_{veg_index}"]
with col:
m = gee_folium.Map()
veg_index_layer = gee_folium.ee_tile_layer(mosaic, {"bands": [veg_index], "min": 0, "max": 1})
if satellite == "COPERNICUS/S2_SR_HARMONIZED":
min_all = 0
max_all = 255
else:
raise ValueError(f"Unknown satellite: {satellite}")
m.add_layer(mosaic.select(veg_index), vis_params)
# add colorbar
# m.add_colorbar(colors=["#000000", "#00FF00"], vmin=0.0, vmax=1.0)
add_geometry_to_maps([m])
m.add_child(colormap)
m.to_streamlit()
for name, key in zip(
["RGB (Least Cloud Tile Crop)", "RGB (Max NDVI Mosaic)", "RGB (Median Mosaic)"],
["image_visual_least_cloud", "mosaic_visual_max_ndvi", "mosaic_visual_median"],
):
st.write(f"{name}
", unsafe_allow_html=True)
cols = st.columns(2)
for col, daterange_str in zip(cols, [year_1, year_2]):
start_date, end_date = daterange_str_to_dates(daterange_str)
mid_date = start_date + (end_date - start_date) / 2
esri_date = min(wayback_mapping.keys(), key=lambda x: abs(pd.to_datetime(x) - mid_date))
with col:
m = gee_folium.Map()
visual_mosaic = result_df.loc[daterange_str, key]
# visual_layer = gee_folium.ee_tile_layer(mosaic, {"bands": ["R", "G", "B"], "min": min_all, "max": max_all})
m.add_layer(visual_mosaic.select(["R", "G", "B"]))
add_geometry_to_maps([m])
m.to_streamlit()
st.write("Esri RGB Imagery
", unsafe_allow_html=True)
cols = st.columns(2)
for col, daterange_str in zip(cols, [year_1, year_2]):
start_date, end_date = daterange_str_to_dates(daterange_str)
mid_date = start_date + (end_date - start_date) / 2
esri_date = min(wayback_mapping.keys(), key=lambda x: abs(pd.to_datetime(x) - mid_date))
with col:
m = leaf_folium.Map()
m.add_tile_layer(wayback_mapping[esri_date], name=f"Esri Wayback Imagery - {esri_date}", attribution="Esri")
add_geometry_to_maps([m])
write_info(
f"""
Esri Imagery - {esri_date.replace('-', '/')}
"""
)
m.to_streamlit()
st.write(
"DEM and Slope from SRTM at 30m resolution
",
unsafe_allow_html=True,
)
cols = st.columns(2)
dem_map, slope_map = get_dem_slope_maps(
ee.Geometry(outer_geometry_gdf.to_crs(4326).geometry.item().__geo_interface__)
)
for col, param_map, title in zip(cols, [dem_map, slope_map], ["DEM Map", "Slope Map"]):
with col:
add_geometry_to_maps([param_map])
write_info(
f"""
{title}
"""
)
param_map.to_streamlit()