Download Satellite Images from NASA Worldview, Add a watermark with the date

Partly taken form some old "watermark" code I found several years ago, this script allows you do download MODIS images from NASA's Worldview image viewer. I then compiled the images into an animated GIF.

# Brian Blaylock
# University of Utah

# Download True Color Images from NASA WorldView
# and add the time stamp to the image

## Images downloaded from NASA's Worldview
## https://earthdata.nasa.gov/labs/worldview/
# 1) zoom in to desired location
# 2) click "take a snapshot" icon
# 3) Draw the region you wish to take a photo
# 4) Modify the URL below, particularly the lat and lon
# 5) Edit the start and end dates

import urllib
from datetime import datetime, timedelta
import numpy as np

from PIL import Image, ImageDraw, ImageFont, ImageEnhance

FONT = 'Arial.ttf'
watermark_label = "THE DATE GOES HERE"


def add_watermark(in_file, text, out_file='watermark.jpg', angle=0, opacity=0.8):
  img = Image.open(in_file).convert('RGB')
  watermark = Image.new('RGBA', img.size, (0,0,0,0))
  size = 2
  n_font = ImageFont.truetype(FONT, size)
  n_width, n_height = n_font.getsize(text)
  text_size_scale = 1.5
  while n_width+n_height < watermark.size[0]/text_size_scale:
    size += 2
    n_font = ImageFont.truetype(FONT, size)
    n_width, n_height = n_font.getsize(text)
  draw = ImageDraw.Draw(watermark, 'RGBA')
  draw.text(((watermark.size[0] - n_width) / 10,
            (watermark.size[1] - n_height) / 100),
  text, font=n_font)
  watermark = watermark.rotate(angle,Image.BICUBIC)
  alpha = watermark.split()[3 ]
  alpha = ImageEnhance.Brightness(alpha).enhance(opacity)
  watermark.putalpha(alpha)
  Image.composite(watermark, img, watermark,).save(out_file, 'JPEG')

##--------------------------------------

outdir = 'satellite_img/'

start_date = datetime(2015,8,15)
end_date = datetime(2015,8,25)


# specify the dates you want to retrieve

date = start_date

while end_date >= date:
  for sat in np.array(["Terra","Aqua"]):
    year = str(date.year)
    dayofyear = str(date.timetuple().tm_yday)
    stringdate = datetime.strftime(date,"%Y-%m-%d")

    URL = "http://map2.vis.earthdata.nasa.gov/image-downloadTIME="+year+dayofyear+"&extent=-116.6972484336448,35.054396923451016,-106.9589671836448,43.896193798451016&epsg=4326&layers=MODIS_"+sat+"_CorrectedReflectance_TrueColor,Coastlines,Reference_Features,MODIS_Fires_All&opacities=1,1,1,1&worldfile=false&format=image/jpeg&width=4433&height=4024"

    #Since the Terra satellite passes over before Aqua
    # we need to save it before Aqua (alphebetical order puts it in wrong order)
    if sat == "Terra":
      sat_order="1Terra"
    if sat == "Aqua":
      sat_order="2Aqua"
    image_name = 'MODIS_TrueColor_'+stringdate+'_'+sat_order+'.jpg'
    urllib.urlretrieve(URL, outdir+image_name)
    add_watermark(outdir+image_name,'MODIS '+sat+' True Color: '+stringdate,outdir+image_name)
    print "Saved", image_name
  date = date+timedelta(days=1)