Unsharp Mask and High Pass Sharpen

Professional image sharpening tool for designers and content creators. All processing happens locally in your browser - no uploads, no data leaves your computer.

Upload an image or drag and drop here

Method

Radius: 1.0 px

Amount: 100 %

Threshold: 0

Upload an image to begin sharpening

Image Details

Dimensions: -

File size: -

Sharpening: -

Before/After Comparison

Upload an image to see before/after comparison

Original Sharpened

Understanding Image Sharpening

Sharpening enhances the apparent clarity of images by emphasizing edges and fine details. Both Unsharp Mask and High Pass techniques work by creating a mask of the image edges and adding them back to the original.

When to Use Each Method

Method	Best For	Radius Range
Unsharp Mask	General photography, moderate sharpening	0.5-2.0 pixels
High Pass	Creative effects, strong edge emphasis	1.0-5.0 pixels

Frequently Asked Questions

Which browsers support this tool?

All modern browsers with Canvas support (Chrome, Firefox, Safari, Edge). WebP and AVIF export depend on browser support.

Why does my image look over-sharpened?

High Amount values or small Radius can cause halos. Try reducing Amount to 100-150% and increasing Radius to 1.5-2.0 pixels.

Does sharpening reduce image quality?

Sharpening enhances perceived detail but can introduce artifacts if over-applied. Always check at 100% zoom before final export.

Formulas and Assumptions

Unsharp Mask: Original + Amount × (Original - GaussianBlur(Original, Radius))

High Pass: Overlay blend of High Pass layer (Radius = same as input)

Gaussian Kernel: Standard 2D Gaussian distribution, kernel size = 2×ceil(3×Radius)+1

For informational and educational purposes only. All processing runs locally in your browser. Color management, codecs and performance depend on your device. Verify critical work with professional tools.

WHATWG HTML Canvas and File APIs | W3C Canvas 2D Context specification | WCAG 2 contrast guidelines

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Unsharp Mask and High Pass Sharpen

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