Raw_To_Reflectance_EnMAP.py

import requests
import os
import subprocess
import numpy as np
import rasterio
import matplotlib.pyplot as plt


# Constants
ENMAP_PORTAL_URL = "https://enmap.org/data_portal/download"
USERNAME = "your_username"  # Replace with your username
PASSWORD = "your_password"  # Replace with your password
L0_FILE_URL = "https://enmap.org/data/L0_sample_file_path"  # Replace with the L0 data file URL
DOWNLOAD_DIR = "./enmap_data"
L0_FILE_PATH = os.path.join(DOWNLOAD_DIR, "enmap_l0_data.tar.gz")
L2_OUTPUT_DIR = "./enmap_reflectance"
RAW_RADIANCE_FILE = "./enmap_data/raw_radiance.tif"  # Replace with the actual radiance file path
REFLECTANCE_FILE = "./enmap_reflectance/reflectance.tif"  # Replace with the actual reflectance file path

# Function to download EnMAP data
def download_enmap_data(url, username, password, output_path):
    """Download EnMAP data using HTTP Basic Authentication."""
    with requests.get(url, auth=(username, password), stream=True) as response:
        if response.status_code == 200:
            os.makedirs(os.path.dirname(output_path), exist_ok=True)
            with open(output_path, "wb") as file:
                for chunk in response.iter_content(chunk_size=8192):
                    file.write(chunk)
            print(f"Downloaded: {output_path}")
        else:
            print(f"Failed to download file. HTTP Status: {response.status_code}, {response.text}")

# Function to convert L0 to L2
def convert_l0_to_l2(l0_file_path, output_dir):
    """Convert L0 data to L2 reflectance using EnMAP-Box or a custom tool."""
    os.makedirs(output_dir, exist_ok=True)

    # Assuming you have a command-line tool for L0 to L2 conversion
    # Replace `enmap_converter` with the actual command or script
    command = [
        "enmap_converter",  # Replace with the actual tool
        "-i", l0_file_path,
        "-o", output_dir,
    ]

    try:
        subprocess.run(command, check=True)
        print(f"Conversion to L2 completed. Output saved to {output_dir}")
    except subprocess.CalledProcessError as e:
        print(f"Error during conversion: {e}")

# Function to plot raster data
def plot_hyperspectral_data(file_path, title, band_index=0):
    """Plot a single band of hyperspectral data."""
    with rasterio.open(file_path) as src:
        data = src.read(band_index + 1)  # Read the specific band (1-based index)
        plt.figure(figsize=(10, 8))
        plt.imshow(data, cmap="viridis")
        plt.colorbar(label="Value")
        plt.title(f"{title} (Band {band_index + 1})")
        plt.xlabel("X Pixel")
        plt.ylabel("Y Pixel")
        plt.show()

# Main Workflow
if __name__ == "__main__":
    # Step 1: Download L0 data
    download_enmap_data(L0_FILE_URL, USERNAME, PASSWORD, L0_FILE_PATH)
    
    # Step 2: Convert L0 to L2 data
    if os.path.exists(L0_FILE_PATH):
        convert_l0_to_l2(L0_FILE_PATH, L2_OUTPUT_DIR)
    else:
        print("L0 file not found. Skipping conversion.")

    # Step 3: Plot raw radiance data
    if os.path.exists(RAW_RADIANCE_FILE):
        plot_hyperspectral_data(RAW_RADIANCE_FILE, "Raw Radiance Data", band_index=0)
    else:
        print("Raw radiance file not found.")

    # Step 4: Plot reflectance data
    if os.path.exists(REFLECTANCE_FILE):
        plot_hyperspectral_data(REFLECTANCE_FILE, "Reflectance Data", band_index=0)
    else:
        print("Reflectance file not found.")