scripts/find_nodata.py

import rasterio
from pathlib import Path
import numpy as np

#areas = {'ATA_MV', 'BRA_SP', 'CHN_WS', 'ESP_EH', 'FIN_LM', 'GER_BN', 'IDN_SV', 
#         'KAZ_AC', 'KSA_WA', 'NAM_HF', 'NZL_KP', 'PHL_TA', 'USA_GC'}

areas = {'ATA_MV'}

path = Path("/home/sabrina/Documents/Tese/05_Dataset/MatchGeo-DEM-v1/data")

print("=" * 70)
print("MatchGeo-DEM NoData Checker")
print("=" * 70)

for location in sorted(areas):
    loc_path = Path(path, f"{location}/{location}.tif")

    if not loc_path.exists():
        print(f"\n⚠️  {location}: File not found at {loc_path}")
        continue

    with rasterio.open(loc_path) as src:
        nodata = src.nodata
        dtype = src.dtypes[0]
        width = src.width
        height = src.height
        is_bigtiff = src.profile.get('bigtiff', 'NO')
        is_tiled = src.profile.get('tiled', False)
        compress = src.profile.get('compress', 'NONE')

        print(f"\n📁 {location}")
        print(f"   File: {loc_path}")
        print(f"   Size: {width} x {height} pixels")
        print(f"   Data type: {dtype}")
        print(f"   Compression: {compress}")
        print(f"   BigTIFF: {is_bigtiff}")
        print(f"   Tiled: {is_tiled}")
        print(f"   Current NoData: {nodata}")

        if nodata == -9999.0:
            print(f"   ✅ NoData already set to -9999.0 — no action needed")
            continue

        if nodata is None:
            print(f"   ⚠️  NoData is NOT SET")
        else:
            print(f"   ⚠️  NoData is {nodata} — needs to be changed to -9999.0")

        # Check actual data range
        band = src.read(1)
        actual_min = np.min(band)
        actual_max = np.max(band)
        print(f"   Data range: {actual_min:.2f} to {actual_max:.2f}")

        # Check for existing -9999 values
        has_neg9999 = np.any(band == -9999)
        print(f"   Contains -9999 values: {has_neg9999}")

        # Check for NaN values
        has_nan = np.isnan(band).any()
        print(f"   Contains NaN values: {has_nan}")

print("\n" + "=" * 70)
print("Run 'fix_nodata.py' to fix any issues found above.")
print("=" * 70)