Hey there! Let's work through your two piexif problems step by step:

1. How to Modify GPS Latitude and Longitude #

First, let's break down that tuple format you're seeing: ((53, 1), (291191, 10000), (0, 1)). This represents the degrees, minutes, seconds of the coordinate, stored as fractions (numerator, denominator) to maintain precision.

For example:

• (53,1) = 53 degrees
• (291191,10000) = 291191/10000 = 29.1191 minutes
• (0,1) = 0 seconds

To set a new coordinate, convert your target lat/long into this fraction tuple format. Also, don't forget to set the reference direction (North/South for latitude, East/West for longitude) using GPSLatitudeRef and GPSLongitudeRef—this is crucial for the coordinate to be interpreted correctly.

Here's an example of setting a new latitude (30° 15' 45" North) and longitude (120° 30' 10" East):

# Convert 30°15'45" North to fraction tuple
new_latitude = ((30, 1), (15, 1), (45, 1))
# Convert 120°30'10" East to fraction tuple
new_longitude = ((120, 1), (30, 1), (10, 1))

# Update the GPS dict
exif_dict['GPS'][piexif.GPSIFD.GPSLatitude] = new_latitude
exif_dict['GPS'][piexif.GPSIFD.GPSLatitudeRef] = "N"  # North
exif_dict['GPS'][piexif.GPSIFD.GPSLongitude] = new_longitude
exif_dict['GPS'][piexif.GPSIFD.GPSLongitudeRef] = "E"  # East

2. Fixing TIFF Metadata Not Saving #

The issue here is that PIL's save() method for TIFF files doesn't handle the exif parameter the same way it does for JPEG. Piexif has a dedicated method to insert modified EXIF data into TIFF files without compressing them: piexif.insert().

Here's how to adjust your code to make this work:

1. First, copy the original TIFF to the new file (preserves full image quality).
2. Then use piexif.insert() to write your modified EXIF bytes into the new TIFF file.

Updated Full Code #

import piexif
from PIL import Image
import shutil

# Disable image size limit
Image.MAX_IMAGE_PIXELS = 1000000000

# File paths (using raw string to avoid escape character issues)
fname_1 = r'D:\EZG\Codding\photo\iiq/eee.tif'
fname_2 = r'D:\EZG\Codding\photo\iiq/eee_change.tif'

# Step 1: Copy original TIFF to preserve quality
shutil.copy(fname_1, fname_2)

# Step 2: Load and modify EXIF data
exif_dict = piexif.load(fname_1)

# Update altitude
exif_dict['GPS'][piexif.GPSIFD.GPSAltitude] = (140, 1)

# Update latitude and longitude (replace with your target values)
new_latitude = ((30, 1), (15, 1), (45, 1))
new_longitude = ((120, 1), (30, 1), (10, 1))
exif_dict['GPS'][piexif.GPSIFD.GPSLatitude] = new_latitude
exif_dict['GPS'][piexif.GPSIFD.GPSLatitudeRef] = "N"
exif_dict['GPS'][piexif.GPSIFD.GPSLongitude] = new_longitude
exif_dict['GPS'][piexif.GPSIFD.GPSLongitudeRef] = "E"

# Dump modified EXIF to bytes
exif_bytes = piexif.dump(exif_dict)

# Step 3: Insert modified EXIF into the copied TIFF
piexif.insert(exif_bytes, fname_2)

This approach ensures your TIFF file stays at full size (no compression) while updating the GPS metadata correctly.

内容的提问来源于stack exchange，提问作者Maxler