Created Radiation, Photo classes and slimmed down main program.

- Radiation creates a list with timezone_aware datetime and radiation in µS/h.
- Photo reads DateTimeOriginal from photo.
- Photo.write_exif compiles new metadata object and writes exif tags to photo.
- Documentd changes in CHANGELOG.md.
- Changed Readme.me to match changes in code.
- Removed obsolete line from .gitignore

.gitignore

@@ -1,5 +1,4 @@
+testdata
 testsource
 testdest
-testdata
-usercomment.sh
 __pycache__

CHANGELOG.md

@@ -8,12 +8,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Added GPX parser
 - Added optional dry-run modifier
 - Made timezone-aware for timesources without timezone
-- Added optional parameter to override timezone to local timezone, defaults to localtime
-- Swith to oop style programming. Made code easier to read.
+- Added optional parameter to override timezone to local timezone, defaults to utc
+- Refactored variable name_scheme.
+- Switch to oop style programming. Made code easier to read.
+- Put CSV processing and Exif reading / writing into a class.
 
 ## [0.2] - 2020-02-05
 ### Added
-- uses pyexiv2 instead of piexif which is also able to tag various camera raw formats, e. g. CR2
+- uses pyexiv2 instead of piexif which is also able to tag various camera raw formats, e. g. CR2 and is capable of writing properly formed UTF-8 strings.
 - added copy function to be able to place files to outdir before modification
 - added verbose output about what it going to happen
 - added table header for output

Readme.md

@@ -1,12 +1,14 @@
 # radiation tagger
 
-exif_rad.py is a simple unix-style cross-platform Python 3 tool which can write certain tags to an image file.
+rad_tag.py is a simple unix-style cross-platform Python 3 tool which can write certain tags to an image file.
 
 It can scan a couple of images, extract their Exif-tags, and compare the `DateTimeOriginal` with other sources.
 
-By now it can parse a .his (CSV) file from a [GeigerLog](https://sourceforge.net/projects/Geigerlog/) file export and calculate the radiation in µS/h using the factor in `SIFACTOR`.
+It can parse a .his (CSV) file from a [GeigerLog](https://sourceforge.net/projects/Geigerlog/) file export and calculate the radiation in µS/h using the factor in `sifactor`.
 
-It then creates a `UserComment` Exif tag with the actual measured radiation at the time the photo has been taken.
+Furthermore it can optionally read a gpx-file, compare the timestamps to 'DateTimeOriginal' and determine closest-matching latitude / longitude. If your gpx-file has times stored including the timezone, you can set --timezone to the local timezone, your camera / geiger counter ran at.
+
+It then creates a `UserComment` with the actual measured radiation at the time the photo has been taken and writes the geocoordinates into the appropiate Exif tags.
 
 ## Dependencies
 Right now it depends on the following non-core Python 3 libraries:
@@ -32,7 +34,7 @@ These exported .his files look like this:
 ## Usage
 
 ```
-usage: exif_rad.py [-h] [-si SIFACTOR] [-tz Timezone] [-d] [-g GPX]
+usage: rad_tag.py [-h] [-si SIFACTOR] [-tz Timezone] [-d] [-g GPX]
                    [-o OUTDIR]
                    CSV Photo [Photo ...]
 
@@ -63,7 +65,7 @@ optional arguments:
 Use test.hisdb.his from current working dir and modify (overwrite) all .CR2 files in place.
 
 ```
-./exif_rad.py test.hisdb.his *.CR2
+./rat_tag.py test.hisdb.his *.CR2
 Modifying photos in place (overwrite)
 filename        date / time          Exif UserComment
 DSC_0196.JPG    2020-03-03 18:33:33  NOT FOUND!
@@ -74,7 +76,7 @@ DSC_0198.JPG    2020-03-03 22:18:13  Radiation ☢ 0.07 µS/h
 Use test.hisdb.his in folder 'testdata', read all .JPG files from 'testsource' and write them to 'testdest'.
 
 ```
-./exif_rad.py testdata/test.hisdb.his -o testdest/ testsource/*.JPG
+./rad_tag.py testdata/test.hisdb.his -o testdest/ testsource/*.JPG
 Modifying photos in testdest/ (copy)
 filename        date / time          Exif UserComment
 DSC_0196.JPG    2020-03-03 18:33:33  NOT FOUND!
@@ -99,6 +101,8 @@ The GMC* defaults are quite sane, but you might want to set the correct serial p
 
 `usbport   = /dev/ttyUSB0`
 
+GeigerLog can also use a bunch of other devices while still outputting a csv-file in compatible format.
+
 ### Using GeigerLog to download history
 
 Now the program can be started by double-clicking `geigerlog` or by executing `./geigerlog` on the command prompt.
@@ -110,11 +114,10 @@ GeigerLog now presents you a rendering of the radiation over time in its main wi
 
 [main_window]: images/geigerlog_main_window.png "GeigerLog Main Window with graph"
 
-Once imported, you can export the history into a hisdb.his-file, which is basically the CSV-file `exif_rad.py` can process. Choose 'History' -> Save History Data into .his file (CSV)'.
+Once imported, you can export the history into a hisdb.his-file, which is basically the CSV-file `rad_tag.py` can process. Choose 'History' -> Save History Data into .his file (CSV)'.
 
 
 ## future possibilities
 
-  * In the future it should also be able to do the same with a gpx-file to extract geolocations and to write them into the appropiate Exif-fields.
   * It might get a setup.py if I want to waste my time on it.
   * I might want to get rid of the requirement to use a bloated GUI application to download the history data off the Geigercounter. There must be a neat working command line tool. Maybe I'll write it myself.

functions.py

@@ -1,14 +1,16 @@
 #!/usr/bin/env python
 # -*- coding: utf-8 -*-
 
-"""Classes used by main program. Handles CSV and GPX processing."""
+''' Classes used by main program. '''
 
 from datetime import datetime
+import pyexiv2
 
 class Radiation:
+    ''' Handles CSV processing.'''
     def __init__(self, timestamp, radiation, local_timezone, si_factor):
         self.timestamp = self._time_conversion(timestamp, local_timezone)
-        self.radiation = self._radiation(radiation, si_factor)
+        self.radiation = self._radiation_conversion(radiation, si_factor)
 
     def __repr__(self):
         return '%s %f µS/h' % (str(self.timestamp), self.radiation)
@@ -19,7 +21,49 @@ class Radiation:
         csv_aware_time = csv_naive_time.astimezone(local_timezone)
         return csv_aware_time
 
-    def _radiation(self, radiation, si_factor):
+    def _radiation_conversion(self, radiation, si_factor):
         # Convert CP/M to µS/h using si_factor
         radiation = round(float(radiation) * si_factor, 2)
         return radiation
+
+class Photo:
+    ''' Reads and writes Exif metadata'''
+    def __init__(self, photo, local_timezone):
+        self.get_date = self._get_creation_date(photo, local_timezone)
+        self.photo = photo
+
+    def __repr__(self):
+        return 'Photo Creation Date: %s' % str(self.get_date)
+
+    def _get_creation_date(self, photo, local_timezone):
+        # Load Exif data from photo
+        metadata = pyexiv2.ImageMetadata(photo)
+        metadata.read()
+        date = metadata['Exif.Photo.DateTimeOriginal']
+        # date.value creates datetime object in pic_naive_time
+        pic_naive_time = date.value
+        # Set timezone
+        pic_aware_time = pic_naive_time.astimezone(local_timezone)
+        return pic_aware_time
+
+    def write_exif(self, radiation, latitude, longitude, dry_run):
+
+        ''' UNTESTED ! '''
+
+        metadata = pyexiv2.ImageMetadata(self.photo)
+        
+        # Set new UserComment
+        new_comment = 'Radiation ☢ ' + str(radiation) + ' µS/h'
+        # Exif tags to write
+        keys = ['Exif.Photo.UserComment', 'Exif.Photo.latitude', 'Exif.Photo.longitude']
+        # Values to write
+        values = [new_comment, latitude, longitude]
+        
+        # Create metadata object with all data to write
+        for key, value in zip(keys, values):
+            metadata[key] = pyexiv2.ExifTag(key, value)
+
+        # Write Exif tags to file, if not in dry-run mode
+        if dry_run == 'True':
+            metadata.write()
+        return new_comment

rad_tag.py

@@ -1,20 +1,18 @@
 #!/usr/bin/env python
 # -*- coding: utf-8 -*-
 
-"""Iterates over a bunch of .jpg or .cr2 files and matches 
+''' Iterates over a bunch of .jpg or .cr2 files and matches 
 DateTimeOriginal from Exif tag to DateTime in a csv log 
 of a GeigerMuellerCounter and writes its value to the UserComment
-Exif tag in µS/h"""
+Exif tag in µS/h '''
 
-from datetime import datetime, timedelta
 import os
 import shutil
 import csv
 import argparse
 import pytz
-import pyexiv2
 import gpxpy
-from functions import Radiation
+from functions import Radiation, Photo
 
 # SIFACTOR for GQ Geiger counters
 
@@ -110,14 +108,14 @@ for src_photo in args.photos:
         else:
             photo = src_photo
 
-    # Load Exif data from image
-    metadata = pyexiv2.ImageMetadata(photo)
-    metadata.read()
-    tag = metadata['Exif.Photo.DateTimeOriginal']
-    # tag.value creates datetime object in pictime
-    pic_naive_time = tag.value
-    # Set timezone
-    pic_time = pic_naive_time.astimezone(local_timezone)
+    pic_aware_time = Photo(photo, local_timezone)
+    print(photo_basename, pic_aware_time)
+
+    # Here the matching magic has to happen
+
+    # Write exif data
+    # exif_tags = Photo.write_exif(radiation, latitude, longitude, args.dry)
+    # print(exif_tags)
 
 # Print table header
 print('{:<15} {:<25} {:<22}'.format('filename', 'date / time', 'Exif UserComment'))