mosaic-rasts-virt

#!/usr/bin/env python3
# Author: Daniel Rode
# Dependencies:
#   python 3.12
#   gdal
#   find
# Created: 30 Sep 2024
# Updated: -


import sys
import tempfile
import subprocess as sp
from sys import exit
from pathlib import Path


HELP_TEXT = """Usage: this.py  TIF_DIR  OUT_TIF_PATH"""


def print2(*args, **kwargs):
  print(*args, file=sys.stderr, **kwargs)

def find(query, dir_list):
  cmd = [
    'find', '-L', *dir_list,
    '-type', 'f',
    '-regex', query,
    '-print0',
  ]
  p = sp.run(cmd, check=True, text=True, capture_output=True)

  return p.stdout.split('\x00')

def gdal_translate(*args):
  args = [str(a) for a in args]
  cmd = [
    'gdal_translate',
    '-co', 'COMPRESS=LZW',
    '-co', 'TILED=YES',
    *args
  ]
  sp.run(cmd, check=True)

def gdal_mosaic(tile_list, dst_pth):
  # Virtual mosaic raster tiles
  cmd = [
    'gdalbuildvrt',
    '-input_file_list', tile_list,
    dst_pth,
  ]
  sp.run(cmd, check=True)

  return dst_pth

def main():
  # Parse command line arguments
  args = sys.argv[1:]
  try:
    src_dir = Path(args[0])
    dst_pth = Path(args[1])
  except IndexError:
    print(HELP_TEXT)
    exit(1)
  if not src_dir.is_dir():
    print2("error: Directory not found:", d)
    exit(1)

  # Use temp directory for intermediate files
  with tempfile.TemporaryDirectory() as tmp_dir:
    tmp_dir = Path(tmp_dir)

    # Create temp text file with list of source raster tiles
    tile_paths = find(r'.*\.tif$', [src_dir])
    tile_list = tmp_dir/"tile_list.txt"
    with tile_list.open('w') as f:
      f.write('\n'.join(tile_paths))

    # Virtual mosaic raster tiles
    gdal_mosaic(tile_list, dst_pth)

if __name__ == '__main__':
  main()