Model grid thumbnail are now jpeg by default.

- TODO: Automatically detect "PNG" files and request jpeg for thumbnails.

__init__.py

@@ -272,11 +272,37 @@ def get_safetensors_image_bytes(path):
     return base64.b64decode(image_data)
 
 
+def get_image_info(image):
+    metadata = None
+    if len(image.info) > 0:
+        metadata = PngInfo()
+        for (key, value) in image.info.items():
+            value_str = str(PIL_cast_serializable(value)) # not sure if this is correct (sometimes includes exif)
+            metadata.add_text(key, value_str)
+    return metadata
+
+
+def image_format_is_equal(f1, f2):
+    if not isinstance(f1, str) or not isinstance(f2, str):
+        return False
+    f1 = f1.upper()
+    f2 = f2.upper()
+    return f1 == f2 or (f1 == "JPG" and f2 == "JPEG") or (f1 == "JPEG" and f2 == "JPG")
+
+
 @server.PromptServer.instance.routes.get("/model-manager/preview/get")
 async def get_model_preview(request):
     uri = request.query.get("uri")
+    quality = request.query.get("quality", "75")
+    try:
+        quality = int(quality)
+    except:
+        quality = 75
+    response_image_format = request.query.get("image-format", None)
+    if isinstance(response_image_format, str):
+        response_image_format = response_image_format.upper()
+
     image_path = no_preview_image
-    image_type = "png"
     file_name = os.path.split(no_preview_image)[1]
     if uri != "no-preview":
         sep = os.path.sep
@@ -285,12 +311,10 @@ async def get_model_preview(request):
         head, extension = split_valid_ext(path, preview_extensions)
         if os.path.exists(path):
             image_path = path
-            image_type = extension.rsplit(".", 1)[1]
-            file_name = os.path.split(head)[1] + "." + image_type
+            file_name = os.path.split(head)[1] + extension
         elif os.path.exists(head) and head.endswith(".safetensors"):
             image_path = head
-            image_type = extension.rsplit(".", 1)[1]
-            file_name = os.path.splitext(os.path.split(head)[1])[0] + "." + image_type
+            file_name = os.path.splitext(os.path.split(head)[1])[0] + extension
 
     w = request.query.get("width")
     h = request.query.get("height")
@@ -314,6 +338,19 @@ async def get_model_preview(request):
         else:
             with open(image_path, "rb") as image:
                 image_data = image.read()
+        fp = io.BytesIO(image_data)
+        with Image.open(fp) as image:
+            image_format = image.format
+            if response_image_format is None:
+                response_image_format = image_format
+            elif not image_format_is_equal(response_image_format, image_format):
+                exif = image.getexif()
+                metadata = get_image_info(image)
+                if response_image_format == 'JPEG' or response_image_format == 'JPG':
+                    image = image.convert('RGB')
+                image_bytes = io.BytesIO()
+                image.save(image_bytes, format=response_image_format, exif=exif, pnginfo=metadata, quality=quality)
+                image_data = image_bytes.getvalue()
     else:
         if image_path.endswith(".safetensors"):
             image_data = get_safetensors_image_bytes(image_path)
@@ -322,7 +359,9 @@ async def get_model_preview(request):
             fp = image_path
 
         with Image.open(fp) as image:
-            format = image.format
+            image_format = image.format
+            if response_image_format is None:
+                response_image_format = image_format
             w0, h0 = image.size
             if w is None:
                 w = (h * w0) // h0
@@ -330,13 +369,7 @@ async def get_model_preview(request):
                 h = (w * h0) // w0
 
             exif = image.getexif()
-
-            metadata = None
-            if len(image.info) > 0:
-                metadata = PngInfo()
-                for (key, value) in image.info.items():
-                    value_str = str(PIL_cast_serializable(value)) # not sure if this is correct (sometimes includes exif)
-                    metadata.add_text(key, value_str)
+            metadata = get_image_info(image)
 
             ratio_original = w0 / h0
             ratio_thumbnail = w / h
@@ -354,8 +387,10 @@ async def get_model_preview(request):
 
             image.thumbnail((w, h))
 
+            if not image_format_is_equal(image_format, response_image_format) and (response_image_format == 'JPEG' or response_image_format == 'JPG'):
+                image = image.convert('RGB')
             image_bytes = io.BytesIO()
-            image.save(image_bytes, format=format, exif=exif, pnginfo=metadata)
+            image.save(image_bytes, format=response_image_format, exif=exif, pnginfo=metadata, quality=quality)
             image_data = image_bytes.getvalue()
 
     return web.Response(
@@ -363,7 +398,7 @@ async def get_model_preview(request):
             "Content-Disposition": f"inline; filename={file_name}",
         },
         body=image_data,
-        content_type="image/" + image_type,
+        content_type="image/" + response_image_format.lower(),
     )