如何解决在 Streamlit 中下载 Google Earth Engine 图像时出现的错误？

Question

我想从 Google Earth Engine 下载 GeoTiff 格式的火灾数据。我正在努力执行下载按钮。它给我一个错误“无效的二进制数据格式：”。我怎样才能让它发挥作用？ 在此输入图片描述谢谢！我将附上错误消息和代码如下：

import datetime
import ee
import streamlit as st
import geemap.foliumap as geemap
import os
import folium

Map = geemap.Map(locate_control=True)

col1, col2, col3, col4, col5= st.columns([1, 1, 1, 2, 2])
with col1:
    longitude = st.number_input("Longitude", 102, 110, 105)
with col2:
    latitude = st.number_input("Latitude", 10, 16, 12)
with col3:
    zoom = st.number_input("Zoom", 0, 20, 7)

Map.setCenter(longitude, latitude, zoom)

with col4:
    start = st.date_input("Start Date for Fire Forest: YYYY/MM/DD", datetime.date(2021, 1, 1))
with col5:
    end = st.date_input("End Date for Fire Forest: YYYY/MM/DD", datetime.date(2021, 1, 3))

start_date = start.strftime("%Y-%m-%d")
end_date = end.strftime("%Y-%m-%d")

countries=ee.FeatureCollection("USDOS/LSIB_SIMPLE/2017")
country = countries.filter(ee.Filter.eq('country_na', 'Cambodia'));
esa = ee.ImageCollection("FIRMS").select('T21').filterBounds(country).filterDate(start_date,end_date).mosaic().clip(country)
esa_vis = {"min": 325,"max": 400,"palette": ['red', 'orange', 'yellow'],}
Map.addLayer(country,{}, name ="Cambodia Global Boundary")
Map.addLayer(esa, esa_vis, 'fire')

#To test export image
out_dir = os.path.join(os.path.expanduser('~'), 'Downloads')
filename = os.path.join(out_dir, 'fire.tiff')
# image = esa.clip(country).unmask()
date=(start_date,end_date)
geemap.ee_export_image(esa, filename=filename, scale=30, region=country, file_per_band=False)
st.download_button('Download fire Output (.tiff)',
                esa,
                file_name = "fire.tiff",
                mime= "image/GeoTIFF")

#Add legend
labels = ['Fire Detection']
colors = ['#FF0000']
Map.add_legend(
            title="Legend",
            labels=labels,
            colors=colors)

#Press on map and show lat and lng
Map.add_child(folium.LatLngPopup())

Map.to_streamlit(height=550)

Answer 1

我不认为

st.download_button

支持所有文件格式。您可能最好使用

st.button

，单击时会导致 文件下载。

Answer 2

我使用了https://developers.google.com/earth-engine/apidocs/ee-image-getdownloadurl中存在的逻辑。

我的代码如下所示：

# Function to export the image to a GeoTIFF file
def export_image(image, date):
    try:
        # Export the image directly to the deployment environment
        url = image.getDownloadURL({
            'name': f'image{date}',
            'scale': 20,
            'crs': 'EPSG:4674',
            'region': roi.geometry().getInfo(),
            'format': 'GEO_TIFF'
        })
        st.sidebar.success(f"Image exported for {date} successfully. Download [here]({url}).")
    except Exception as e:
        st.sidebar.error(f"Error exporting the image: {str(e)}")

...

# Button to trigger the data download
if st.sidebar.button("Download Data"):
    # Check if the ROI is defined
    if 'roi' in locals() and roi is not None:
        # Export the selected collection to GeoTIFF files
        for date in selected_dates:
            # Filter the collection for the selected date
            selected_collection_date = selected_collection.filter(ee.Filter.eq('data', date))
            # Export the first image in the filtered collection
            export_image(selected_collection_date.first(), date)
    else:
        st.warning("Please select an area of interest before downloading.")