Subject Mask Generator - AI Alpha Matte Creator

Generate alpha masks from photos using AI. Create black and white mattes for compositing. Perfect for video editing and Photoshop. Browser-based.

Source Image

Drop image here or click to select

Use Cases

Photoshop: Layer masks, selections
After Effects: Track mattes, rotoscoping
Premiere Pro: Luma key effects
DaVinci Resolve: Alpha output
Compositing: Green screen replacement

Mask Colors

White: Fully visible (subject)
Black: Fully transparent (background)
Gray: Semi-transparent (soft edges)

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Frequently Asked Questions

A subject mask (alpha matte) is a grayscale image where white represents the subject and black represents the background. Used in compositing to precisely control which areas are visible or affected by effects.

Load the mask as a layer mask or alpha channel. White areas become visible, black becomes transparent. This gives precise control over selections, especially for complex edges like hair.

Import the mask as a luma matte in Premiere Pro, After Effects, DaVinci Resolve, or Final Cut. Apply it to control transparency or effects. Great for keying footage without green screen.

Masks give more editing flexibility. You can adjust the mask separately, apply feathering, modify edge hardness, or use it for effects (blur, color grading) that only affect specific areas.

Hard masks have sharp edges (pure black/white). Soft masks have gradual transitions (gray values) for natural-looking composites. This tool produces soft masks for realistic edges.

Yes. Toggle 'Invert Mask' to swap black and white. This is useful when you want to affect the background instead of the subject, or for masking out rather than masking in.

No. All AI processing happens locally in your browser. Your images never leave your device. The neural network runs via WebAssembly for complete privacy.

The mask matches your input image resolution. For best results in professional workflows, use high-resolution source images to get detailed edge information.

The AI produces optimized edges automatically. For additional refinement, import the mask into Photoshop and use Refine Edge or Select and Mask for final adjustments.

People, animals, and distinct objects work best. The AI handles hair, fur, and complex edges well. Very transparent or very thin subjects may need manual touch-up.

Subject Mask Generator - AI Alpha Matte Creator

Source Image

Use Cases

Mask Colors

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