# This script takes *.BIL files that are still packed in a *.zip file

# extracts them and converts the output to GeoTIFF files

# The actual example below handles SRTM files as downloaded from EarthExplorer.usgs.gov



# Some information on how to do this came from this post:

# http://gis.stackexchange.com/questions/42584/how-to-call-gdal-translate-from-python-code





import os, gdal, zipfile

from gdalconst import *



# Function converts one BIL file to a GeoTiff file

def BILtoTIF(inBilPath,outTifPath):

    

    inBil = gdal.Open(inBilPath)           # InBIL    

    driver = gdal.GetDriverByName('Gtiff') # Output Driver    

    outTif =  driver.CreateCopy( outTifPath, inBil, 0 )    



    # Properly close the datasets to flush to disk

    inBil = None

    outTif = None



    

# Actual example on how to convert an entire folder    

    

inFol = ".../BIL_SRTM_Original/"           # Folder containing the zipped BIL files

outFol = ".../Single_TIFF_SRTM/"           # Folder to save converted *.tif files to

scratchFol = ".../Scratch/Convert/"        # extract files here first before converting, files in here will be deleted again



for zipFile in os.listdir(inFol):               # iterate through zip files in folder

    if zipFile[-3:].lower() == "zip":

        zipName = inFol+zipFile

        zipped = zipfile.ZipFile(zipName, mode='r')

        zipped.extractall(scratchFol, pwd=None) # extract all contents in zip to scratch

        

        # convert BIL files in scratch 

        for j in os.listdir(scratchFol):        

            if j[-3:].lower() == "bil":

                BIL = scratchFol + j

                out = outFol+zipFile[:8]+".tif"

                BILtoTIF(BIL, out)

        

        # remove all file contents in scratch 

        for old_file in os.listdir(scratchFol):

            file_path = os.path.join(scratchFol, old_file)

            os.remove(file_path)

        

        print(zipFile, " done")