diff --git a/.gitignore b/.gitignore
index 5d381cc..fe9260d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,5 @@
+.idea
+
 # ---> Python
 # Byte-compiled / optimized / DLL files
 __pycache__/
@@ -15,7 +17,6 @@ dist/
 downloads/
 eggs/
 .eggs/
-lib/
 lib64/
 parts/
 sdist/
diff --git a/README.md b/README.md
index 300a0c2..10991e1 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,26 @@
 # gpx-to-image-tags
+_Geotag your photos from a GPX track._
 
-Read a GPX track and correlate that to the time photos were taken.
\ No newline at end of file
+This is a simple script used to add geotags (geographic metadata locating where the photo was taken) to images taken by
+a non-GPS camera.
+
+It reads the time a photo was taken and then finds the closest point in the GPX track.
+
+## Install
+
+1. `pip install -r requirements.txt`
+
+## Use
+
+```
+python3 main.py <path to the folder containing your photos> <path to GPX file>
+```
+
+You might need the `--timezone` argument. Double check the EXIF times are correct via `identify -verbose`.
+
+<br>
+
+Optional Arguments:
+
+- `--max-diff`: Maximum allowed difference in seconds between image timestamp and track point. Default: 300 (5 minutes).
+- `--timezone`: Three letter timezone the photos are in (e.g. EST). Default: auto-detect your local timezone.
\ No newline at end of file
diff --git a/lib/__init__.py b/lib/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/lib/geotags.py b/lib/geotags.py
new file mode 100644
index 0000000..dbfa8a8
--- /dev/null
+++ b/lib/geotags.py
@@ -0,0 +1,76 @@
+import datetime
+from fractions import Fraction
+from typing import Union
+
+import piexif
+
+"""
+Source: https://gist.github.com/c060604/8a51f8999be12fc2be498e9ca56adc72
+"""
+
+
+def to_deg(value, loc):
+    """convert decimal coordinates into degrees, munutes and seconds tuple
+
+    Keyword arguments: value is float gps-value, loc is direction list ["S", "N"] or ["W", "E"]
+    return: tuple like (25, 13, 48.343 ,'N')
+    """
+    if value < 0:
+        loc_value = loc[0]
+    elif value > 0:
+        loc_value = loc[1]
+    else:
+        loc_value = ""
+    abs_value = abs(value)
+    deg = int(abs_value)
+    t1 = (abs_value - deg) * 60
+    min = int(t1)
+    sec = round((t1 - min) * 60, 5)
+    return deg, min, sec, loc_value
+
+
+def change_to_rational(number):
+    """convert a number to rantional
+
+    Keyword arguments: number
+    return: tuple like (1, 2), (numerator, denominator)
+    """
+    f = Fraction(str(number))
+    return f.numerator, f.denominator
+
+
+def generate_geotags(lat: float, lon: float, alt: Union[int, float], timestamp_obj: datetime.datetime, original_exif: dict):
+    lat_deg = to_deg(lat, ["S", "N"])
+    lng_deg = to_deg(lon, ["W", "E"])
+
+    exiv_lat = (change_to_rational(lat_deg[0]), change_to_rational(lat_deg[1]), change_to_rational(lat_deg[2]))
+    exiv_lng = (change_to_rational(lng_deg[0]), change_to_rational(lng_deg[1]), change_to_rational(lng_deg[2]))
+
+    # Convert date and time to the format required by EXIF
+    datestamp = timestamp_obj.strftime("%Y:%m:%d")
+    timestamp = (change_to_rational(timestamp_obj.hour), change_to_rational(timestamp_obj.minute), change_to_rational(timestamp_obj.second))
+
+    if alt < 0:
+        altitude_ref = 1
+        altitude = abs(alt)
+    else:
+        altitude_ref = 0
+        altitude = alt
+
+    gps_ifd = {
+        piexif.GPSIFD.GPSVersionID: (2, 0, 0, 0),
+        piexif.GPSIFD.GPSAltitudeRef: altitude_ref,
+        piexif.GPSIFD.GPSAltitude: change_to_rational(round(altitude)),
+        piexif.GPSIFD.GPSLatitudeRef: lat_deg[3],
+        piexif.GPSIFD.GPSLatitude: exiv_lat,
+        piexif.GPSIFD.GPSLongitudeRef: lng_deg[3],
+        piexif.GPSIFD.GPSLongitude: exiv_lng,
+        piexif.GPSIFD.GPSDateStamp: datestamp,
+        piexif.GPSIFD.GPSTimeStamp: timestamp,
+    }
+    gps_exif = {"GPS": gps_ifd}
+
+    # Update original exif data to include GPS tag.
+    original_exif.update(gps_exif)
+
+    return original_exif
diff --git a/lib/gpx.py b/lib/gpx.py
new file mode 100644
index 0000000..582a98b
--- /dev/null
+++ b/lib/gpx.py
@@ -0,0 +1,32 @@
+from datetime import timedelta
+
+import gpxpy
+from gpxpy.gpx import GPXTrackPoint
+
+
+def get_closest_point(gpx, timestamp, max_diff) -> GPXTrackPoint | None:
+    closest_point = None
+    closest_diff = timedelta.max
+
+    for track in gpx.tracks:
+        for segment in track.segments:
+            for point in segment.points:
+                diff = abs(point.time - timestamp)
+                if diff < closest_diff and diff.total_seconds() <= max_diff:
+                    closest_diff = diff
+                    closest_point = point
+
+    return closest_point
+
+
+def get_gpx_data(file):
+    gpx_file = open(file, 'r')
+    gpx = gpxpy.parse(gpx_file)
+
+    data = []
+    for track in gpx.tracks:
+        for segment in track.segments:
+            for point in segment.points:
+                data.append((point.time, point.latitude, point.longitude))
+
+    return data
diff --git a/lib/image.py b/lib/image.py
new file mode 100644
index 0000000..c7dbe3c
--- /dev/null
+++ b/lib/image.py
@@ -0,0 +1,23 @@
+from datetime import datetime
+
+import pytz
+from PIL.ExifTags import TAGS
+
+
+def get_image_timestamp(img, timezone):
+    exif = img._getexif()
+    if not exif:
+        raise ValueError("No EXIF metadata found")
+
+    found_timestamp = None
+
+    for (idx, tag) in TAGS.items():
+        if tag == 'DateTime':
+            found_timestamp = exif.get(idx)
+        elif tag == 'DateTimeOriginal':
+            found_timestamp = exif.get(idx)
+
+    if found_timestamp:
+        dt = datetime.strptime(found_timestamp, '%Y:%m:%d %H:%M:%S')
+        tz = pytz.timezone(timezone)
+        return tz.localize(dt)
diff --git a/lib/time.py b/lib/time.py
new file mode 100644
index 0000000..c06acf4
--- /dev/null
+++ b/lib/time.py
@@ -0,0 +1,7 @@
+from datetime import datetime
+
+from tzlocal import get_localzone
+
+
+def get_local_timezone():
+    return datetime.now(tz=get_localzone()).strftime('%Z')
diff --git a/main.py b/main.py
new file mode 100644
index 0000000..9c45a34
--- /dev/null
+++ b/main.py
@@ -0,0 +1,57 @@
+import argparse
+from pathlib import Path
+
+import gpxpy
+import piexif
+import pytz
+from PIL import Image
+
+from lib.geotags import generate_geotags
+from lib.gpx import get_closest_point
+from lib.image import get_image_timestamp
+from lib.time import get_local_timezone
+
+
+def main(args):
+    with open(args.gpx, 'r') as gpxfile:
+        gpx = gpxpy.parse(gpxfile)
+
+    for file in args.photos.glob('*'):
+        if file.name.lower().endswith(('.jpg', '.jpeg')):
+            img = Image.open(file)
+            timestamp = get_image_timestamp(img, args.timezone)
+            del img
+            if not timestamp:
+                print(f'FAIL - "{file.name}" does not have a timestamp.')
+                continue
+            point = get_closest_point(gpx, timestamp, args.max_diff)
+            if not point:
+                point_forced = get_closest_point(gpx, timestamp, 99999999999999999999999999)
+                print(f'FAIL - Could not match image "{file.name}" @ {timestamp}. Closest point: {point_forced.latitude},{point_forced.longitude} @ {point_forced.time.astimezone(pytz.timezone(args.timezone))}')
+                continue
+            else:
+                original_exif = piexif.load(str(file))
+                geotags = generate_geotags(point.latitude, point.longitude, point.elevation, point.time, original_exif)
+                exif_bytes = piexif.dump(geotags)
+                piexif.insert(exif_bytes, str(file))
+                print('OKAY - ', file.name)
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(description='Add location tags to photos based on a GPX track.')
+    parser.add_argument('photos', help='Path to the directory containing the photos')
+    parser.add_argument('gpx', help='Path to the GPX file')
+    parser.add_argument('--max-diff', type=int, default=300, help='Maximum allowed difference in seconds between image timestamp and track point. Default: 300')
+    parser.add_argument('--timezone', default=get_local_timezone(), help='Three letter timezone the photos are in (e.g. EST). Default: auto-detect your local timezone')
+    args = parser.parse_args()
+
+    args.photos = Path(args.photos).expanduser().absolute().resolve()
+    if args.photos.is_file() or not args.photos.exists():
+        print('Invalid path to photos. Must be a directory.')
+        quit(1)
+
+    args.gpx = Path(args.gpx).expanduser().absolute().resolve()
+    if args.gpx.is_dir() or not args.gpx.exists():
+        print('Invalid path to GPX file.')
+        quit(1)
+    main(args)
diff --git a/requirements.txt b/requirements.txt
new file mode 100644
index 0000000..39cbe40
--- /dev/null
+++ b/requirements.txt
@@ -0,0 +1,5 @@
+gpxpy==1.6.2
+pillow==10.2.0
+tzlocal==5.2
+pytz==2024.1
+piexif==1.1.3
\ No newline at end of file