Layer Flatten

Merges all layers of a stack into a single image, like Layer → Flatten Image in Photoshop. Use it as the last step of a compositing chain.

In ComfyUI	Add Node → ComfyUI-JH-PixelPro → compositing → Compositing: Layer Flatten
Good for	Getting a normal image out of a layer stack so you can preview, save or keep editing

When to use it

A layer stack is not an image yet. Until you flatten it, you cannot preview or save it. Layer Flatten renders the stack from the bottom layer up: each layer is mixed in using its blend mode, opacity, fill, mask and clipping.

Quick start

1. Build a stack with Layer Stack Start and Layer Add.
2. Connect the last LAYER_STACK to Layer Flatten → Preview Image or Save Image.

Settings

Setting	Default	What it does	Tip
stack	—	The layer stack to render.	Connect the last node of your chain.

Output	Type	Meaning
IMAGE	IMAGE	The merged picture, values clamped to 0..1.

Tips from retouching

• Flatten once, at the end. A flattened image no longer lets you adjust the individual layers.
• You can flatten the same stack at two points (for example before and after one layer) to make a before/after comparison.
• Run QA Image Diff on the original and the flattened image to see how much the composite changed.

Under the hood

Runs compose_stack from core/blend_modes.py. An empty stack raises an error. Source: nodes/layer_compositing.py.

Related nodes

• Layer Stack Start
• Layer Add
• Layer Group

Example workflow

Layer compositing: 5-layer cinematic grade. Copy workflows/sample_portrait.jpg into ComfyUI/input/.