dodge and burn, dissolve, and arithmetic blend

post_processing/arithmetic_blend.py

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+import torch
+
+class ArithmeticBlend:
+    def __init__(self):
+        pass
+
+    @classmethod
+    def INPUT_TYPES(s):
+        return {
+            "required": {
+                "image1": ("IMAGE",),
+                "image2": ("IMAGE",),
+                "blend_mode": (["add", "subtract", "difference"],),
+            },
+        }
+
+    RETURN_TYPES = ("IMAGE",)
+    FUNCTION = "arithmetic_blend_images"
+
+    CATEGORY = "postprocessing"
+
+    def arithmetic_blend_images(self, image1: torch.Tensor, image2: torch.Tensor, blend_mode: str):
+        if blend_mode == "add":
+            blended_image = self.add(image1, image2)
+        elif blend_mode == "subtract":
+            blended_image = self.subtract(image1, image2)
+        elif blend_mode == "difference":
+            blended_image = self.difference(image1, image2)
+        else:
+            raise ValueError(f"Unsupported arithmetic blend mode: {blend_mode}")
+
+        blended_image = torch.clamp(blended_image, 0, 1)
+        return (blended_image,)
+
+    def add(self, img1, img2):
+        return img1 + img2
+
+    def subtract(self, img1, img2):
+        return img1 - img2
+
+    def difference(self, img1, img2):
+        return torch.abs(img1 - img2)
+
+NODE_CLASS_MAPPINGS = {
+    "ArithmeticBlend": ArithmeticBlend,
+}