Mostly so I myself can remember how to do it, here is how to create a random geotiff with GDAL in Python

**Note**: the width and height are given in opposite order in the GDAL raster and numpy arrays!

import osr import numpy import gdal import math width = 4000 height = 3000 format = "GTiff" driver = gdal.GetDriverByName( format ) dst_ds = driver.Create( "test.tiff", width, height, 1, gdal.GDT_Byte ) dst_ds.SetGeoTransform( [ 444720, 30, 0, 3751320, 0, -30 ] ) srs = osr.SpatialReference() srs.ImportFromEPSG(25832) dst_ds.SetProjection( srs.ExportToWkt() ) raster = numpy.zeros( (height, width), dtype=numpy.uint32 ) color_range = 2**8 seed = math.pi**10 for i in range(height): for j in range(width): color = (seed*i*j) % color_range raster[i][j] = color dst_ds.GetRasterBand(1).WriteArray( raster ) |

It's kind of slow, so perhaps the operation can be speeded up somehow? The result looks kind of nice though (image created with width and height both 4000):

So, not completely random.