JezK
Edit File: rel.py
#!/usr/bin/env python3 ############################################################################### # $Id$ # # Project: GDAL Python samples # Purpose: Script to produce a shaded relief image from elevation data # Author: Andrey Kiselev, dron@remotesensing.org # ############################################################################### # Copyright (c) 2003, Andrey Kiselev <dron@remotesensing.org> # Copyright (c) 2009, Even Rouault <even dot rouault at spatialys.com> # # Permission is hereby granted, free of charge, to any person obtaining a # copy of this software and associated documentation files (the "Software"), # to deal in the Software without restriction, including without limitation # the rights to use, copy, modify, merge, publish, distribute, sublicense, # and/or sell copies of the Software, and to permit persons to whom the # Software is furnished to do so, subject to the following conditions: # # The above copyright notice and this permission notice shall be included # in all copies or substantial portions of the Software. # # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS # OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL # THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING # FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER # DEALINGS IN THE SOFTWARE. ############################################################################### import math import sys import numpy as np from osgeo import gdal, gdal_array gdal.TermProgress = gdal.TermProgress_nocb # ============================================================================= def Usage(): print("Usage: rel.py -lsrcaz azimuth -lsrcel elevation [-elstep step]") print(" [-dx xsize] [-dy ysize] [-b band] [-ot type] infile outfile") print("Produce a shaded relief image from elevation data") print("") print( " -lsrcaz azimuth Azimuth angle of the diffuse light source (0..360 degrees)" ) print( " -lsrcel elevation Elevation angle of the diffuse light source (0..180 degrees)" ) print( " -elstep step Elevation change corresponding to a change of one grey level" ) print(" (default 1)") print( " -dx xsize X and Y dimensions (in meters) of one pixel on the ground" ) print(" -dy ysize (taken from the geotransform matrix by default)") print(" -r range Dynamic range for output image (default 255)") print(" -b band Select a band number to convert (default 1)") print(" -ot type Data type of the output dataset") print(" (Byte/Int16/UInt16/UInt32/Int32/Float32/Float64/") print(" CInt16/CInt32/CFloat32/CFloat64, default is Byte)") print(" infile Name of the input file") print(" outfile Name of the output file") print("") return 2 def ParseType(typ): if typ == "Byte": return gdal.GDT_Byte if typ == "Int16": return gdal.GDT_Int16 if typ == "UInt16": return gdal.GDT_UInt16 if typ == "Int32": return gdal.GDT_Int32 if typ == "UInt32": return gdal.GDT_UInt32 if typ == "Float32": return gdal.GDT_Float32 if typ == "Float64": return gdal.GDT_Float64 if typ == "CInt16": return gdal.GDT_CInt16 if typ == "CInt32": return gdal.GDT_CInt32 if typ == "CFloat32": return gdal.GDT_CFloat32 if typ == "CFloat64": return gdal.GDT_CFloat64 return gdal.GDT_Byte def main(argv=sys.argv): infile = None outfile = None iBand = 1 # The first band will be converted by default driver_name = "GTiff" typ = gdal.GDT_Byte lsrcaz = None lsrcel = None elstep = 1.0 xsize = None ysize = None dyn_range = 255.0 # Parse command line arguments. i = 1 while i < len(argv): arg = argv[i] if arg == "-b": i += 1 iBand = int(argv[i]) elif arg == "-ot": i += 1 typ = ParseType(argv[i]) elif arg == "-lsrcaz": i += 1 lsrcaz = float(argv[i]) elif arg == "-lsrcel": i += 1 lsrcel = float(argv[i]) elif arg == "-elstep": i += 1 elstep = float(argv[i]) elif arg == "-dx": i += 1 xsize = float(argv[i]) elif arg == "-dy": i += 1 ysize = float(argv[i]) elif arg == "-r": i += 1 dyn_range = float(argv[i]) elif infile is None: infile = arg elif outfile is None: outfile = arg else: return Usage() i += 1 if infile is None: return Usage() if outfile is None: return Usage() if lsrcaz is None: return Usage() if lsrcel is None: return Usage() # translate angles from degrees to radians lsrcaz = lsrcaz / 180.0 * math.pi lsrcel = lsrcel / 180.0 * math.pi lx = -math.sin(lsrcaz) * math.cos(lsrcel) ly = math.cos(lsrcaz) * math.cos(lsrcel) lz = math.sin(lsrcel) lxyz = math.sqrt(lx**2 + ly**2 + lz**2) indataset = gdal.Open(infile, gdal.GA_ReadOnly) if indataset is None: print("Cannot open", infile) return 2 if indataset.RasterXSize < 3 or indataset.RasterYSize < 3: print("Input image is too small to process, minimum size is 3x3") return 3 out_driver = gdal.GetDriverByName(driver_name) outdataset = out_driver.Create( outfile, indataset.RasterXSize, indataset.RasterYSize, indataset.RasterCount, typ, ) outband = outdataset.GetRasterBand(1) geotransform = indataset.GetGeoTransform() projection = indataset.GetProjection() if xsize is None: xsize = abs(geotransform[1]) if ysize is None: ysize = abs(geotransform[5]) inband = indataset.GetRasterBand(iBand) if inband is None: print("Cannot load band", iBand, "from the", infile) return 2 numtype = gdal_array.GDALTypeCodeTonpTypeCode(typ) outline = np.empty((1, inband.XSize), numtype) prev = inband.ReadAsArray(0, 0, inband.XSize, 1, inband.XSize, 1)[0] outband.WriteArray(outline, 0, 0) gdal.TermProgress(0.0) cur = inband.ReadAsArray(0, 1, inband.XSize, 1, inband.XSize, 1)[0] outband.WriteArray(outline, 0, inband.YSize - 1) gdal.TermProgress(1.0 / inband.YSize) dx = 2 * xsize dy = 2 * ysize for i in range(1, inband.YSize - 1): next_ = inband.ReadAsArray(0, i + 1, inband.XSize, 1, inband.XSize, 1)[0] dzx = (cur[0:-2] - cur[2:]) * elstep dzy = (prev[1:-1] - next_[1:-1]) * elstep nx = -dy * dzx ny = dx * dzy nz = dx * dy nxyz = nx * nx + ny * ny + nz * nz nlxyz = nx * lx + ny * ly + nz * lz cosine = dyn_range * (nlxyz / (lxyz * np.sqrt(nxyz))) cosine = np.clip(cosine, 0.0, dyn_range) outline[0, 1:-1] = cosine.astype(numtype) outband.WriteArray(outline, 0, i) prev = cur cur = next_ # Display progress report on terminal gdal.TermProgress(float(i + 1) / (inband.YSize - 1)) outdataset.SetGeoTransform(geotransform) outdataset.SetProjection(projection) return 0 if __name__ == "__main__": sys.exit(main(sys.argv))