Update app.py

app.py

@@ -1,50 +1,82 @@
 import gradio as gr
 from PIL import Image
-import piexif
-import piexif.helper
-from datetime import datetime
 import os
+from datetime import datetime
+import struct
+
+def create_xmp_block(width, height):
+    """Create XMP metadata block following ExifTool's exact format."""
+    xmp = (
+        f'<?xpacket begin="" id="W5M0MpCehiHzreSzNTczkc9d"?>\n'
+        f'<x:xmpmeta xmlns:x="adobe:ns:meta/" x:xmptk="ExifTool">\n'
+        f'<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">\n'
+        f'<rdf:Description rdf:about=""\n'
+        f'xmlns:GPano="http://ns.google.com/photos/1.0/panorama/"\n'
+        f'GPano:ProjectionType="equirectangular"\n'
+        f'GPano:UsePanoramaViewer="True"\n'
+        f'GPano:FullPanoWidthPixels="{width}"\n'
+        f'GPano:FullPanoHeightPixels="{height}"\n'
+        f'GPano:CroppedAreaImageWidthPixels="{width}"\n'
+        f'GPano:CroppedAreaImageHeightPixels="{height}"\n'
+        f'GPano:CroppedAreaLeftPixels="0"\n'
+        f'GPano:CroppedAreaTopPixels="0"/>\n'
+        f'</rdf:RDF>\n'
+        f'</x:xmpmeta>\n'
+        f'<?xpacket end="w"?>'
+    )
+    return xmp
+
+def write_xmp_to_jpg(input_path, output_path, width, height):
+    """Write XMP metadata to JPEG file following ExifTool's method."""
+    # Read the original JPEG
+    with open(input_path, 'rb') as f:
+        data = f.read()
+    
+    # Find the start of image marker
+    if data[0:2] != b'\xFF\xD8':
+        raise ValueError("Not a valid JPEG file")
+    
+    # Create XMP data
+    xmp_data = create_xmp_block(width, height)
+    
+    # Create APP1 segment for XMP
+    app1_marker = b'\xFF\xE1'
+    xmp_header = b'http://ns.adobe.com/xap/1.0/\x00'
+    xmp_bytes = xmp_data.encode('utf-8')
+    length = len(xmp_header) + len(xmp_bytes) + 2  # +2 for length bytes
+    length_bytes = struct.pack('>H', length)
+    
+    # Construct new file content
+    output = bytearray()
+    output.extend(data[0:2])  # SOI marker
+    output.extend(app1_marker)
+    output.extend(length_bytes)
+    output.extend(xmp_header)
+    output.extend(xmp_bytes)
+    output.extend(data[2:])  # Rest of the original file
+    
+    # Write the new file
+    with open(output_path, 'wb') as f:
+        f.write(output)
 
 def add_360_metadata(input_image):
     """Add 360 photo metadata to an image file."""
     try:
-        # Open the image
+        # Open and verify the image
         img = Image.open(input_image)
+        if img.width != 2 * img.height:
+            raise gr.Error("Image must have 2:1 aspect ratio for equirectangular projection")
         
-        # Prepare XMP metadata for 360 photo
-        xmp_metadata = (
-            '<?xpacket begin="" id="W5M0MpCehiHzreSzNTczkc9d"?>\n'
-            '<x:xmpmeta xmlns:x="adobe:ns:meta/">\n'
-            '<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">\n'
-            '<rdf:Description rdf:about="" xmlns:GPano="http://ns.google.com/photos/1.0/panorama/">\n'
-            '<GPano:ProjectionType>equirectangular</GPano:ProjectionType>\n'
-            '<GPano:UsePanoramaViewer>True</GPano:UsePanoramaViewer>\n'
-            '<GPano:CroppedAreaImageWidthPixels>' + str(img.width) + '</GPano:CroppedAreaImageWidthPixels>\n'
-            '<GPano:CroppedAreaImageHeightPixels>' + str(img.height) + '</GPano:CroppedAreaImageHeightPixels>\n'
-            '<GPano:FullPanoWidthPixels>' + str(img.width) + '</GPano:FullPanoWidthPixels>\n'
-            '<GPano:FullPanoHeightPixels>' + str(img.height) + '</GPano:FullPanoHeightPixels>\n'
-            '<GPano:CroppedAreaLeftPixels>0</GPano:CroppedAreaLeftPixels>\n'
-            '<GPano:CroppedAreaTopPixels>0</GPano:CroppedAreaTopPixels>\n'
-            '</rdf:Description>\n'
-            '</rdf:RDF>\n'
-            '</x:xmpmeta>\n'
-            '<?xpacket end="w"?>'
-        )
-
-        # Create temporary filename for output
+        # Create output filename
         timestamp = datetime.now().strftime("%Y%m%d_%H%M%S")
         output_filename = f"360_photo_{timestamp}.jpg"
+        output_path = os.path.join("/tmp", output_filename)
         
-        # Create EXIF dictionary with XMP metadata
-        exif_dict = {"0th": {}, "Exif": {}, "GPS": {}, "1st": {}, "thumbnail": None}
-        exif_dict["0th"][piexif.ImageIFD.XPComment] = xmp_metadata.encode('utf-16')
-        
-        # Convert EXIF dictionary to bytes
-        exif_bytes = piexif.dump(exif_dict)
+        # First save as high-quality JPEG
+        img.save(output_path, "JPEG", quality=95)
         
-        # Save image with metadata
-        output_path = os.path.join("/tmp", output_filename)
-        img.save(output_path, "JPEG", exif=exif_bytes, quality=95)
+        # Then inject XMP metadata directly into JPEG file
+        write_xmp_to_jpg(output_path, output_path, img.width, img.height)
         
         return output_path
     
@@ -57,7 +89,10 @@ iface = gr.Interface(
     inputs=gr.Image(type="filepath", label="Upload 360° Photo"),
     outputs=gr.Image(type="filepath", label="360° Photo with Metadata"),
     title="360° Photo Metadata Adder",
-    description="Upload an equirectangular 360° photo to add necessary metadata for Google Photos and other 360° viewers. Your image should have a 2:1 aspect ratio for best results.",
+    description=(
+        "Upload an equirectangular 360° photo to add metadata for Google Photos and other 360° viewers.\n"
+        "Important: Image must have 2:1 aspect ratio (width = 2 × height)."
+    ),
     examples=[],
     cache_examples=False
 )