1hew-ComfyUI-1hewNodes/web/docs/1hew_ImageBlendModeByCSS/en.md

Image Blend Mode by CSS - CSS-Compatible Image Blending

Node Purpose: Image Blend Mode by CSS reproduces CSS blending semantics between a base image and an overlay image, with explicit blend_mode, overall blend_percentage, and optional overlay_mask control. Includes HSL-based modes for hue, saturation, color, and luminosity.

Inputs

Name	Port	Type	Default	Range	Description
overlay_image	-	IMAGE	-	-	Overlay image batch placed over base_image.
base_image	-	IMAGE	-	-	Base image batch.
blend_mode	-	COMBO	normal	normal / multiply / screen / overlay / darken / lighten / color_dodge / color_burn / hard_light / soft_light / difference / exclusion / hue / saturation / color / luminosity	CSS blend algorithm to apply.
blend_percentage	-	FLOAT	100.0	0–100	Global opacity (percent) of the blended result.
overlay_mask	optional	MASK	-	-	Optional mask; restricts blended replacement to mask>0 areas.
invert_mask	-	BOOLEAN	false	-	Invert overlay_mask before application.

Outputs

Name	Type	Description
image	IMAGE	Batch of blended images.

Features

• CSS-accurate formulas: match typical CSS semantics for multiply, screen, overlay, darken, lighten, color dodge/burn, hard/soft light, difference, exclusion.
• HSL modes: hue, saturation, color, luminosity implemented via RGB↔HSL conversion.
• Opacity control: blend_percentage (0–100) linearly mixes base and blended results.
• RGBA normalization: flattens alpha to white background for consistent RGB blending.
• Size alignment and masking: overlay is resized to base; optional mask is resized and broadcast to RGB.
• Robust batching: mismatched base/overlay/mask batch sizes loop across the maximum batch size.

Typical Usage

• Photo toning: multiply for shadows, screen for highlights, overlay to boost contrast.
• Color-only mixing: use HSL modes to transfer hue/saturation/luminosity while keeping base structure.
• Region-specific blending: feed overlay_mask to limit blending; enable invert_mask to flip selection.
• Strength control: tune blend_percentage to match the desired effect intensity.

Notes & Tips

• When overlay size differs, it is resized with Lanczos before blending.
• HSL conversion clamps values to valid ranges; results are returned in RGB.
• color_dodge and color_burn handle boundary cases to avoid infinities and negatives.