cvp
Sep 11, 2016 - 17:42
A little script to show how to extract exifs from a photo, get its GPS tags and display an Apple map in the sheet view, with a pin where the photo has been taken.
Select a photo in a mail (long press on the photo) or in the photos app (or anywhere else) and run the script in the Pythonista share sheet.
The script only runs in Python 2 because appex.get_image crashes in Python 3 (bug for @omz).
In appex mode, dezooming too much crashes, perhaps due to a memory problem.
The MKMapView part was initially copied from OMZ MapView demo
then "cleaned" to keep the easiest code as possible
#!python2
# coding: utf-8
#
# Needs Python 2 because appex.get_image crashes in Python 3
#
# MKMapView part initially copied from OMZ MapView demo
# https://gist.github.com/omz/451a6685fddcf8ccdfc5
# then "cleaned" to keep the easiest code as possible
#
# In appex mode, dezooming too much crashes, perhaps memory problem?
import console
import clipboard
from objc_util import *
import ctypes
import ui
from PIL import Image
from PIL.ExifTags import TAGS,GPSTAGS
import appex
#import photos # used to test in non-appex mode
class CLLocationCoordinate2D (Structure):
_fields_ = [('latitude', c_double), ('longitude', c_double)]
class MKCoordinateSpan (Structure):
_fields_ = [('d_lat', c_double), ('d_lon', c_double)]
class MKCoordinateRegion (Structure):
_fields_ = [('center', CLLocationCoordinate2D), ('span', MKCoordinateSpan)]
def get_gps(image):
gps_latitude = None
gps_latitude_ref = None
gps_longitude = None
gps_longitude_ref = None
exif_info = image._getexif() # Extract exifs from photo
if exif_info:
for tag, value in exif_info.items(): # Loop on exifs of photo
decoded = TAGS.get(tag, tag) # Exif code
if decoded == "GPSInfo": # Exif is GPSInfo
for t in value: # Loop on sub-exifs
sub_decoded = GPSTAGS.get(t, t) # Sub-exif code
if sub_decoded == 'GPSLatitude':
gps_latitude = value[t]
elif sub_decoded == 'GPSLatitudeRef':
gps_latitude_ref = value[t]
elif sub_decoded == 'GPSLongitude':
gps_longitude = value[t]
elif sub_decoded == 'GPSLongitudeRef':
gps_longitude_ref = value[t]
if gps_latitude and gps_latitude_ref and gps_longitude and gps_longitude_ref:
lat = convert_to_degrees(gps_latitude)
lat_lon_txt = str(lat)+gps_latitude_ref
if gps_latitude_ref != "N":
lat = 0 - lat
lon = convert_to_degrees(gps_longitude)
lat_lon_txt = lat_lon_txt+' - '+str(lon)+gps_longitude_ref
if gps_longitude_ref != "E":
lon = 0 - lon
return lat, lon, lat_lon_txt
return False,False,None
def convert_to_degrees(value):
# convert the GPS coordinates d m s to degrees in float
d0 = value[0][0]
d1 = value[0][1]
d = float(d0) / float(d1)
m0 = value[1][0]
m1 = value[1][1]
m = float(m0) / float(m1)
s0 = value[2][0]
s1 = value[2][1]
s = float(s0) / float(s1)
return d + (m / 60.0) + (s / 3600.0)
class MapView(ui.View):
@on_main_thread
def __init__(self, *args, **kwargs):
ui.View.__init__(self, *args, **kwargs)
MKMapView = ObjCClass('MKMapView')
frame = CGRect(CGPoint(0, 0), CGSize(self.width, self.height))
self.mk_map_view = MKMapView.alloc().initWithFrame_(frame)
flex_width, flex_height = (1<<1), (1<<4)
self.mk_map_view.setAutoresizingMask_(flex_width|flex_height)
self_objc = ObjCInstance(self)
self_objc.addSubview_(self.mk_map_view)
self.mk_map_view.release()
@on_main_thread
def add_pin(self, lat, lon, title):
'''Add a pin annotation to the map'''
MKPointAnnotation = ObjCClass('MKPointAnnotation')
coord = CLLocationCoordinate2D(lat, lon)
annotation = MKPointAnnotation.alloc().init().autorelease()
annotation.setTitle_(title)
annotation.setCoordinate_(coord, restype=None, argtypes=[CLLocationCoordinate2D])
self.mk_map_view.addAnnotation_(annotation)
@on_main_thread
def set_region(self, lat, lon, d_lat, d_lon, animated=False):
'''Set latitude/longitude of the view's center and the zoom level (specified implicitly as a latitude/longitude delta)'''
region = MKCoordinateRegion(CLLocationCoordinate2D(lat, lon), MKCoordinateSpan(d_lat, d_lon))
self.mk_map_view.setRegion_animated_(region, animated, restype=None, argtypes=[MKCoordinateRegion, c_bool])
def will_close(self):
appex.finish()
def main():
#----- Main process -----
console.clear()
if not appex.is_running_extension():
#img = photos.pick_image()
console.hud_alert('Must run in appex mod','error')
return
else:
img = appex.get_image(image_type='pil')
if img == None:
console.alert('No image passed','','Ok',hide_cancel_button=True)
return
lat,lon, lat_lon_txt = get_gps(img)
if not lat or not lon:
console.alert('No GPS tags in image','','Ok',hide_cancel_button=True)
return
# Hide script
back = MapView(frame=(0, 0, 540, 620))
back.background_color='white'
back.name = 'GPS = '+lat_lon_txt
back.present('sheet', hide_title_bar=False)
back.set_region(lat, lon, 0.05, 0.05, animated=True)
back.add_pin(lat, lon,str((lat, lon)))
# Protect against import
if __name__ == '__main__':
main()