Distance transform from geoJSON to a bumpy array

distancexform.py

import json
from shapely.geometry import Polygon, shape, Point
import gdal
import numpy as np
import sys
fn = sys.argv[1]
path = sys.argv[2]

def Pixel2World ( geoMatrix, i , j ):
    ulX = geoMatrix[0]
    ulY = geoMatrix[3]
    xDist = geoMatrix[1]
    yDist = geoMatrix[5]
    rtnX = geoMatrix[2]
    rtnY = geoMatrix[4]
    return(1.0 * i * xDist  + ulX, -1.0 * j * xDist + ulY)
ds8 = gdal.Open(path+'8band/'+'8band_'+fn+'.tif')
ds3 = gdal.Open(path+'3band/'+'3band_'+fn+'.tif')
geoTrans = ds8.GetGeoTransform()
with open(path + 'vectorData/geoJson/'+fn+'_Geo.geojson','r') as f:
    js = json.load(f)
    dist = np.zeros((ds8.RasterXSize, ds8.RasterYSize))
    for i in range(ds8.RasterXSize):
        for j in range(ds8.RasterYSize):
            point = Point(Pixel2World( geoTrans, i , j ))
            pd = -100000.0
            for feature in js['features']:
                polygon = shape(feature['geometry'])
                newpd = point.distance(polygon.boundary)
                 if False == polygon.contains(point):
                     newpd = -1.0 * newpd
                 if newpd > pd :
                     pd = newpd
             dist[i,j] = pd
np.save(path+'CosmiQ_distance/'+fn+'.distance',dist)

Thank you for the code! Is there a faster algorithm/library for this procedure? It takes very long if the the image size and the number of objects is big.

Great and thank you very much for providing code. Can you please help me how to show dist ?

As it is now, it contains 5 indentation errors, fixed version here:

https://gist.github.com/bquast/eec2b10fe2594c166e2bfd2c5d67dde5

Hello. Can somebody show me a json file?