def contour_images(xstart,xend,ystart,yend,latlen,longlen,centerlat,centerlong,coordinates,uid,fieldid,imagedate):
	import math
	import matplotlib.path
	from matplotlib.path import Path
	import numpy as np
	import cv2
	from PIL import Image
	from merge_contour_images import merge_contour_images
	import collections
	coordinates = collections.OrderedDict(sorted(coordinates.items()))
	print(coordinates)
	path_codes = []
	p1= len(coordinates)
	x_pixel_nos = np.zeros(p1)
	y_pixel_nos = np.zeros(p1)
	temp_list = []
	half_lat_len = longlen/2
	half_long_len = latlen/2
	x_pixel_length = xend-xstart
	y_pixel_length = yend-ystart
	pixelsperlat = x_pixel_length/latlen
	pixelsperlong = y_pixel_length/longlen
	iter_path = 0
	for k,v in coordinates.items():
		temp_lat = v['Latitude']
		temp_long = v['Longitude']
		temp_lat = float(temp_lat)
		temp_long = float(temp_long)
		lat_distance_from_center = centerlat-temp_lat
		long_distance_from_center = centerlong-temp_long
		lat_distance_from_start_edge = half_lat_len-lat_distance_from_center
		long_distance_from_start_edge = half_long_len - long_distance_from_center
		temp_x = round(lat_distance_from_start_edge*pixelsperlat)
		temp_y = round(long_distance_from_start_edge*pixelsperlong)
		temp_list.append([temp_x,temp_y])
		if iter_path == 0:
			path_codes.append(Path.MOVETO)
		elif (iter_path<p1)&(iter_path>0):
			path_codes.append(Path.LINETO)
		else:
			path_codes.append(Path.CLOSEPOLY)
		iter_path = iter_path+1
		
	polygon = np.array(temp_list)
	left = np.min(polygon,axis=0)
	right = np.max(polygon,axis=0)
	x = np.arange(math.ceil(left[0]),math.floor(right[0])+1)
	y = np.arange(math.ceil(left[1]),math.floor(right[1])+1)
	xv,yv = np.meshgrid(x,y,indexing='xy')
	points = np.hstack((xv.reshape((-1,1)),yv.reshape((-1,1))))
	path = matplotlib.path.Path(polygon,path_codes)
	mask = path.contains_points(points)
	mask.shape = xv.shape
	print('mask')
	#print(mask)
	h_mask, w_mask = mask.shape
	
	
	mask_img = np.zeros([h_mask,w_mask])
	for py in range(0,h_mask):
		for px in range(0,w_mask):
			if mask[py][px]==True:
				mask_img[py][px]=255
				
			else:
				mask_img[py][px]=0
	status = cv2.imwrite('mask_img.png',mask_img)
	mask_img = cv2.imread('mask_img.png',0)
	h_mask = int(1.2*h_mask)
	w_mask = int(1.2*w_mask)
	mask_img = cv2.resize(mask_img,(w_mask,h_mask))
	M = cv2.getRotationMatrix2D((round(w_mask/2),round(h_mask/2)),90,1.0)
	rotated_mask = cv2.warpAffine(mask_img,M,(h_mask,w_mask))
	status = cv2.imwrite('mask_img.png',rotated_mask)
	mask = rotated_mask
	
	merge_contour_images(uid,'ndvi',mask,half_lat_len,half_long_len,fieldid,imagedate)
	merge_contour_images(uid,'ndwi',mask,half_lat_len,half_long_len,fieldid,imagedate)
	merge_contour_images(uid,'ndre',mask,half_lat_len,half_long_len,fieldid,imagedate)
	merge_contour_images(uid,'vari',mask,half_lat_len,half_long_len,fieldid,imagedate)
	return