Add 2 nodes, remove alpha + convert image to grayscale

README.md

@@ -1,4 +1,4 @@
-# 🔗 Comfyui : Bjornulf_custom_nodes v0.4 🔗
+# 🔗 Comfyui : Bjornulf_custom_nodes v0.5 🔗
 
 # Dependencies
 
@@ -6,10 +6,12 @@
 
 # 📝 Changelog
 
-- **v0.2 Ollama**: Improve ollama node with system prompt + model selection.
-- **v0.3 Save Image to Folder**: Add a new node : Save image to a chosen folder.
-- **v0.3 Save Images**: Add comfyui Metadata / workflow to all my image-related nodes.
-- **v0.4 Images to video**: Support transparency option with webm format, options encoders. As well as input for audio stream. 
+- **v0.2**: Improve ollama node with system prompt + model selection.
+- **v0.3**: Add a new node : Save image to a chosen folder.
+- **v0.3**: Add comfyui Metadata / workflow to all my image-related nodes.
+- **v0.4**: Support transparency option with webm format, options encoders. As well as input for audio stream. 
+- **v0.5**: New node : Remove image transparency (alpha) - Fill alpha channel with solid color.
+- **v0.5**: New node : Image to grayscale (black & white) - Convert an image to grayscale.
 
 # 📝 Nodes descriptions
 
@@ -140,3 +142,19 @@ Create a ping-pong effect from a list of images (from a video) by reversing the
 Combine a sequence of images into a video file.  
 ❓ I made this node because it supports transparency with webm format. (Needed for rembg)  
 Temporary images are stored in the folder `ComfyUI/temp_images_imgs2video/` as well as the wav audio file.
+
+## 22 - 🔲 Remove image Transparency (alpha)
+![Images to Video](screenshots/remove_alpha.png)
+
+**Description:**  
+Remove transparency from an image by filling the alpha channel with a solid color. (black, white or greenscreen)  
+Of course it takes in an image with transparency, liek from rembg nodes.  
+Necessary for some nodes that don't support transparency.  
+
+## 23 - 🔲 Image to grayscale (black & white)
+![Images to Video](screenshots/grayscale.png)
+
+**Description:**  
+Convert an image to grayscale (black & white)  
+Example : I sometimes use it with Ipadapter to disable color influence.  
+But you can sometimes also want a black and white image...  

__init__.py

@@ -25,6 +25,8 @@ from .save_api_image import SaveApiImage
 from .save_img_to_folder import SaveImageToFolder
 from .resize_image import ResizeImage
 from .loop_my_combos_samplers_schedulers import LoopCombosSamplersSchedulers
+from .remove_transparency import RemoveTransparency
+from .image_to_grayscale import GrayscaleTransform
 
 # from .CUSTOM_STRING import CustomStringType
 
@@ -32,6 +34,8 @@ NODE_CLASS_MAPPINGS = {
     # "Bjornulf_CustomStringType": CustomStringType,
     "Bjornulf_ollamaLoader": ollamaLoader,
     "Bjornulf_WriteText": WriteText,
+    "Bjornulf_RemoveTransparency": RemoveTransparency,
+    "Bjornulf_GrayscaleTransform": GrayscaleTransform,
     # "Bjornulf_WriteImageEnvironment": WriteImageEnvironment,
     # "Bjornulf_WriteImageCharacters": WriteImageCharacters,
     # "Bjornulf_WriteImageCharacter": WriteImageCharacter,
@@ -65,6 +69,8 @@ NODE_DISPLAY_NAME_MAPPINGS = {
     "Bjornulf_ShowText": "👁 Show (Text)",
     "Bjornulf_ShowInt": "👁 Show (Int)",
     "Bjornulf_ShowFloat": "👁 Show (Float)",
+    "Bjornulf_GrayscaleTransform": "🔲 Image to grayscale (black & white)",
+    "Bjornulf_RemoveTransparency": "🔲 Remove image Transparency (alpha)",
     "Bjornulf_ResizeImage": "📏 Resize Image",
     "Bjornulf_SaveImagePath": "🖼 Save Image (exact path, exact name) ⚠️💣",
     "Bjornulf_SaveImageToFolder": "🖼📁 Save Image to a folder",

image_to_grayscale.py

@@ -0,0 +1,39 @@
+import torch
+
+class GrayscaleTransform:
+    @classmethod
+    def INPUT_TYPES(s):
+        return {
+            "required": {
+                "image": ("IMAGE",),
+                "preserve_alpha": ("BOOLEAN", {"default": False}),
+            },
+        }
+
+    RETURN_TYPES = ("IMAGE",)
+    FUNCTION = "transform_to_grayscale"
+
+    CATEGORY = "Bjornulf"
+
+    def transform_to_grayscale(self, image, preserve_alpha):
+        # Check if the image has an alpha channel
+        has_alpha = image.shape[3] == 4
+
+        # Extract RGB channels
+        rgb = image[:, :, :, :3]
+
+        # Convert to grayscale using the luminosity method
+        # Weights are based on human perception of color
+        grayscale = 0.2989 * rgb[:,:,:,0] + 0.5870 * rgb[:,:,:,1] + 0.1140 * rgb[:,:,:,2]
+        
+        # Expand dimensions to match original shape
+        grayscale = grayscale.unsqueeze(-1).repeat(1, 1, 1, 3)
+
+        if has_alpha and preserve_alpha:
+            # If the original image had an alpha channel and we want to preserve it
+            alpha = image[:, :, :, 3:4]
+            result = torch.cat([grayscale, alpha], dim=3)
+        else:
+            result = grayscale
+
+        return (result,)

remove_transparency.py

@@ -0,0 +1,47 @@
+import torch
+
+class RemoveTransparency:
+    @classmethod
+    def INPUT_TYPES(s):
+        return {
+            "required": {
+                "image": ("IMAGE",),
+                "recover_background": ("BOOLEAN", {"default": False}),
+                "background_color": (["black", "white", "greenscreen"], {"default": "black"}),
+            },
+        }
+
+    RETURN_TYPES = ("IMAGE",)
+    FUNCTION = "process_transparency"
+
+    CATEGORY = "Bjornulf"
+
+    def process_transparency(self, image, recover_background, background_color):
+        # Check if the image has an alpha channel
+        if image.shape[3] == 4:
+            rgb = image[:, :, :, :3]
+            alpha = image[:, :, :, 3:4]
+            
+            if recover_background:
+                result = rgb
+            else:
+                # Create background color tensor
+                if background_color == "white":
+                    bg_color = torch.ones_like(rgb)
+                elif background_color == "greenscreen":
+                    bg_color = torch.zeros_like(rgb)
+                    bg_color[:, :, :, 1] = 1  # Set green channel to 1
+                else:  # black
+                    bg_color = torch.zeros_like(rgb)
+                
+                # Blend the image with the background color
+                result = rgb * alpha + bg_color * (1 - alpha)
+        else:
+            # If there's no alpha channel, return the original image
+            result = image
+
+        # Ensure the output is always 3 channels (RGB)
+        if result.shape[3] == 4:
+            result = result[:, :, :, :3]
+
+        return (result,)