Update README.md

Author: Silver-Sky

README.md

@@ -75,4 +75,15 @@ You can compress the output `.mov` file using ffmpeg and H.264 by specifying the
 python pyelapse.py create-timelapse /path/to_image_folder/ --output output.mov --fps 24 --crf 23
 ```
 
-This will create `output.mov` and then compress it to `output_compressed.mov` using ffmpeg.
+This will create `output.mov` and then compress it to `output_compressed.mov` using ffmpeg.
+
+### Timestamps on frames
+
+To overlay the EXIF date/time in the lower-right corner of each frame while creating the timelapse, add `--timestamp`:
+
+```bash
+python pyelapse.py create-timelapse /path/to_image_folder/ --output output.mp4 --fps 24 --timestamp
+```
+
+- If EXIF `DateTimeOriginal` is present, that timestamp is used.
+- If EXIF is missing, the script falls back to the filename (if it contains digits), otherwise to the current date/time at build.