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JPEG coordinates from GPS track
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| import piexif | |
| from datetime import datetime, timedelta, timezone | |
| import gpxpy | |
| import os | |
| def geotag_photos(offset=0, datefmt="b'%Y:%m:%d %H:%M:%S'", | |
| recursive=False, max_secs=300): | |
| """ | |
| Appends coordinates to metadata of JPEG images in the current working directory | |
| (recursive search is possible). Note that it changes the metadata of original | |
| files. Be careful! | |
| The coordinates are taken from the GPX track files | |
| located in the working directory based on | |
| temporal proximity of track nodes and JPEG timestamps. | |
| There are too many ways to store timezone info in JPEG. | |
| Thus, here it is passed as the 'offset' argument. | |
| Parameters | |
| ---------- | |
| offset : int or float, default 0 | |
| Timezone info (in hours ahead GMT). | |
| datefmt : string, default "b'%Y:%m:%d %H:%M:%S'" | |
| JPEG timestamp format (passed to datetime.strptime). | |
| recursive : bool, default False | |
| Recursive search of JPEG and GPX files, starting from current working directory | |
| max_secs : int or float, default 300 | |
| Desired temporal accuracy of geotag coordinates (in seconds). | |
| If a photo is geotagged using a point with timestamp differing from | |
| JPEG timestamp by more than max_secs, the function gives a warning. | |
| """ | |
| # Extracting all jpg names from working directory | |
| if recursive: | |
| files = [dir[0] + '/' + f for dir in os.walk('./') for f in dir[2]] | |
| else: | |
| files = [*os.walk('./')][0][2] | |
| # Parsing JPG metadata and GPX tracks | |
| photos = {f: piexif.load(f) for f in files if f.lower().endswith('.jpg')} | |
| gpsdata = [gpxpy.parse(open(f)) for f in files if f.lower().endswith('.gpx')] | |
| # Comparing photo timestamp with gpx points timestamps | |
| success = [] | |
| no_timestamp = [] | |
| for file, photo in photos.items(): | |
| if 36867 in photo['Exif']: | |
| photo_time = datetime.strptime(f"{photo['Exif'][36867]}", datefmt) | |
| photo_time = photo_time.replace(tzinfo=timezone(timedelta(seconds = offset * 3600))) | |
| for gpx in gpsdata: | |
| for track in gpx.tracks: | |
| for segment in track.segments: | |
| if segment.points[0].time<=photo_time<=segment.points[-1].time: | |
| deltas = [] | |
| for point in segment.points: | |
| deltas.append(point.time - photo_time) | |
| deltas = list(map(abs, deltas)) | |
| geotag = segment.points[deltas.index(min(deltas))] | |
| lat = int(abs(geotag.latitude) * 100000) | |
| lon = int(abs(geotag.longitude) * 100000) | |
| alt = int(abs(geotag.elevation) * 100) | |
| if geotag.latitude > 0: | |
| latr = b'N' | |
| else: | |
| latr = b'S' | |
| if geotag.longitude > 0: | |
| lonr = b'E' | |
| else: | |
| lonr = b'W' | |
| if geotag.elevation > 0: | |
| altr = 0 | |
| else: | |
| altr = 1 | |
| zeroth_ifd = photo['0th'] | |
| exif_ifd = photo['Exif'] | |
| gps_ifd = {piexif.GPSIFD.GPSVersionID: (2, 0, 0, 0), | |
| piexif.GPSIFD.GPSLatitudeRef: latr, | |
| piexif.GPSIFD.GPSLatitude: ((lat, 100000), (0, 1), (0, 1)), | |
| piexif.GPSIFD.GPSLongitudeRef: lonr, | |
| piexif.GPSIFD.GPSLongitude: ((lon, 100000), (0, 1), (0, 1)), | |
| piexif.GPSIFD.GPSAltitudeRef: altr, | |
| piexif.GPSIFD.GPSAltitude: (alt, 100) | |
| } | |
| first_ifd = photo['1st'] | |
| thumbnail = photo['thumbnail'] | |
| exif_dict = {"0th":zeroth_ifd, "Exif":exif_ifd, "GPS":gps_ifd, "1st":first_ifd, "thumbnail":thumbnail} | |
| exif_bytes = piexif.dump(exif_dict) | |
| piexif.insert(exif_bytes, file) | |
| text = f'{file} geotag found in track {track.name}' | |
| if min(deltas) < timedelta(0, max_secs): | |
| print(text) | |
| else: | |
| print(text + f' Warning! Timedelta between photo and track node exceeds {max_secs} seconds' + \ | |
| f' ({min(deltas).total_seconds()} seconds)') | |
| success.append(file) | |
| break | |
| else: | |
| continue | |
| break | |
| else: | |
| continue | |
| break | |
| else: | |
| continue | |
| break | |
| else: | |
| no_timestamp.append(file) | |
| # Returning paths to photos we failed to geotag | |
| unsuccessful = [i for i in photos.keys() if i not in success + no_timestamp] | |
| if len(no_timestamp) > 0: | |
| print(f'No timestamp: {chr(10).join(no_timestamp)}') # chr(10) stands for '\n' | |
| if len(unsuccessful) > 0: | |
| print(f'No relevant track segments: {chr(10).join(unsuccessful)}') |
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