From a073b82751ab9826fd9c28384a6912f010c3aade Mon Sep 17 00:00:00 2001
From: Will Miao <13051207myq@gmail.com>
Date: Wed, 21 May 2025 19:17:12 +0800
Subject: [PATCH] Enhance WebP image saving: add EXIF data and workflow
 metadata support. Fixes #193

---
 py/nodes/save_image.py | 30 ++++++++++++++++++++++--------
 1 file changed, 22 insertions(+), 8 deletions(-)

diff --git a/py/nodes/save_image.py b/py/nodes/save_image.py
index 69a68847..68b2769a 100644
--- a/py/nodes/save_image.py
+++ b/py/nodes/save_image.py
@@ -379,14 +379,28 @@ class SaveImage:
                             print(f"Error adding EXIF data: {e}")
                     img.save(file_path, format="JPEG", **save_kwargs)
                 elif file_format == "webp":
-                    # For WebP, also use piexif for metadata
-                    if metadata:
-                        try:
-                            exif_dict = {'Exif': {piexif.ExifIFD.UserComment: b'UNICODE\0' + metadata.encode('utf-16be')}}
-                            exif_bytes = piexif.dump(exif_dict)
-                            save_kwargs["exif"] = exif_bytes
-                        except Exception as e:
-                            print(f"Error adding EXIF data: {e}")
+                    # For WebP, use exif data in a ComfyUI-compatible format
+                    try:
+                        # Get exif from image
+                        exif = img.getexif()
+                        
+                        # Add metadata if available
+                        if metadata:
+                            exif[piexif.ExifIFD.UserComment] = b'UNICODE\0' + metadata.encode('utf-16be')
+                        
+                        # Add workflow if embed_workflow is enabled
+                        if embed_workflow and extra_pnginfo is not None:
+                            # Format the workflow with "Workflow:" prefix for ComfyUI compatibility
+                            workflow_json = json.dumps(extra_pnginfo["workflow"])
+                            # Store workflow in ImageDescription tag (0x010e)
+                            exif[piexif.ImageIFD.ImageDescription] = "Workflow:" + workflow_json
+                        
+                        # Update save_kwargs with exif data
+                        save_kwargs["exif"] = exif.tobytes()
+                        
+                    except Exception as e:
+                        print(f"Error adding EXIF/workflow data to WebP: {e}")
+                    
                     img.save(file_path, format="WEBP", **save_kwargs)
                 
                 results.append({