def create_dist_map(rasterSrc, vectorSrc, npDistFileName='',
noDataValue=0, burn_values=255,
dist_mult=1, vmax_dist=64):
source_ds = ogr.Open(vectorSrc)
source_layer = source_ds.GetLayer()
srcRas_ds = gdal.Open(rasterSrc)
cols = srcRas_ds.RasterXSize
rows = srcRas_ds.RasterYSize
geoTrans, poly, ulX, ulY, lrX, lrY = gT.getRasterExtent(srcRas_ds)
transform_WGS84_To_UTM, transform_UTM_To_WGS84, utm_cs \
= gT.createUTMTransform(poly)
line = ogr.Geometry(ogr.wkbLineString)
line.AddPoint(geoTrans[0], geoTrans[3])
line.AddPoint(geoTrans[0]+geoTrans[1], geoTrans[3])
line.Transform(transform_WGS84_To_UTM)
metersIndex = line.Length()
memdrv = gdal.GetDriverByName('MEM')
dst_ds = memdrv.Create('', cols, rows, 1, gdal.GDT_Byte)
dst_ds.SetGeoTransform(srcRas_ds.GetGeoTransform())
dst_ds.SetProjection(srcRas_ds.GetProjection())
band = dst_ds.GetRasterBand(1)
band.SetNoDataValue(noDataValue)
gdal.RasterizeLayer(dst_ds, [1], source_layer, burn_values=[burn_values])
srcBand = dst_ds.GetRasterBand(1)
memdrv2 = gdal.GetDriverByName('MEM')
prox_ds = memdrv2.Create('', cols, rows, 1, gdal.GDT_Int16)
prox_ds.SetGeoTransform(srcRas_ds.GetGeoTransform())
prox_ds.SetProjection(srcRas_ds.GetProjection())
proxBand = prox_ds.GetRasterBand(1)
proxBand.SetNoDataValue(noDataValue)
opt_string = 'NODATA='+str(noDataValue)
options = [opt_string]
gdal.ComputeProximity(srcBand, proxBand, options)
memdrv3 = gdal.GetDriverByName('MEM')
proxIn_ds = memdrv3.Create('', cols, rows, 1, gdal.GDT_Int16)
proxIn_ds.SetGeoTransform(srcRas_ds.GetGeoTransform())
proxIn_ds.SetProjection(srcRas_ds.GetProjection())
proxInBand = proxIn_ds.GetRasterBand(1)
proxInBand.SetNoDataValue(noDataValue)
opt_string2 = 'VALUES='+str(noDataValue)
options = [opt_string, opt_string2]
gdal.ComputeProximity(srcBand, proxInBand, options)
proxIn = gdalnumeric.BandReadAsArray(proxInBand)
proxOut = gdalnumeric.BandReadAsArray(proxBand)
proxTotal = proxIn.astype(float) - proxOut.astype(float)
proxTotal = proxTotal*metersIndex
proxTotal *= dist_mult
proxTotal = np.clip(proxTotal, -1*vmax_dist, 1*vmax_dist)
if npDistFileName != '':
np.save(npDistFileName, proxTotal)
def create_dist_map(rasterSrc,
vectorSrc,
npDistFileName='',
noDataValue=0,
burn_values=1,
dist_mult=1,
vmax_dist=64):
'''
Create building signed distance transform from Yuan 2016
(https://arxiv.org/pdf/1602.06564v1.pdf).
vmax_dist: absolute value of maximum distance (meters) from building edge
Adapted from createNPPixArray in labeltools
'''
## open source vector file that truth data
source_ds = ogr.Open(vectorSrc)
source_layer = source_ds.GetLayer()
## extract data from src Raster File to be emulated
## open raster file that is to be emulated
srcRas_ds = gdal.Open(rasterSrc)
cols = srcRas_ds.RasterXSize
rows = srcRas_ds.RasterYSize
geoTrans, poly, ulX, ulY, lrX, lrY = gT.getRasterExtent(srcRas_ds)
transform_WGS84_To_UTM, transform_UTM_To_WGS84, utm_cs \
= gT.createUTMTransform(poly)
line = ogr.Geometry(ogr.wkbLineString)
line.AddPoint(geoTrans[0], geoTrans[3])
line.AddPoint(geoTrans[0] + geoTrans[1], geoTrans[3])
line.Transform(transform_WGS84_To_UTM)
metersIndex = line.Length()
memdrv = gdal.GetDriverByName('MEM')
dst_ds = memdrv.Create('', cols, rows, 1, gdal.GDT_Byte)
dst_ds.SetGeoTransform(srcRas_ds.GetGeoTransform())
dst_ds.SetProjection(srcRas_ds.GetProjection())
band = dst_ds.GetRasterBand(1)
band.SetNoDataValue(noDataValue)
gdal.RasterizeLayer(dst_ds, [1], source_layer, burn_values=[burn_values])
srcBand = dst_ds.GetRasterBand(1)
memdrv2 = gdal.GetDriverByName('MEM')
prox_ds = memdrv2.Create('', cols, rows, 1, gdal.GDT_Int16)
prox_ds.SetGeoTransform(srcRas_ds.GetGeoTransform())
prox_ds.SetProjection(srcRas_ds.GetProjection())
proxBand = prox_ds.GetRasterBand(1)
proxBand.SetNoDataValue(noDataValue)
opt_string = 'NODATA=' + str(noDataValue)
options = [opt_string]
gdal.ComputeProximity(srcBand, proxBand, options)
memdrv3 = gdal.GetDriverByName('MEM')
proxIn_ds = memdrv3.Create('', cols, rows, 1, gdal.GDT_Int16)
proxIn_ds.SetGeoTransform(srcRas_ds.GetGeoTransform())
proxIn_ds.SetProjection(srcRas_ds.GetProjection())
proxInBand = proxIn_ds.GetRasterBand(1)
proxInBand.SetNoDataValue(noDataValue)
opt_string2 = 'VALUES=' + str(noDataValue)
options = [opt_string, opt_string2]
#options = ['NODATA=0', 'VALUES=0']
gdal.ComputeProximity(srcBand, proxInBand, options)
proxIn = gdalnumeric.BandReadAsArray(proxInBand)
proxOut = gdalnumeric.BandReadAsArray(proxBand)
proxTotal = proxIn.astype(float) - proxOut.astype(float)
proxTotal = proxTotal * metersIndex
proxTotal *= dist_mult
# clip array
proxTotal = np.clip(proxTotal, -1 * vmax_dist, 1 * vmax_dist)
if npDistFileName != '':
# save as numpy file since some values will be negative
np.save(npDistFileName, proxTotal)
#cv2.imwrite(npDistFileName, proxTotal)
return proxTotal