Image Fisheye 🔵

About the Image Fisheye tool

The Image Fisheye tool runs entirely in your browser. Drop or select an image, set the Strength slider from 0% to 100%, and click Apply. The tool applies a barrel distortion using inverse pixel mapping: for each output pixel, it computes the normalized distance r from the image center (0 at center, 1 at the inscribed circle edge). The source distance is computed as r' = r + strength · r · (1 − r), which magnifies the center and compresses the edges. Pixels outside the inscribed circle are set to transparent. Source coordinates are sampled with bilinear interpolation for smooth edges. Nothing is uploaded; all processing is local.

How to use it

1. Click the drop zone or drop an image file onto it.
2. Drag the Strength slider — higher values produce a stronger bulge.
3. Click Apply to render the fisheye effect onto the image.
4. Click Download to save, Reset to restore, or Clear to start over.

Frequently asked questions

What distortion model is used? A barrel distortion with the formula r' = r + strength · r · (1 − r). At 0% strength the image is unchanged. At 100% the center is maximally magnified while edges compress toward the inscribed circle.

Why are corners transparent? Pixels outside the inscribed circle (radius = min(width, height) / 2) have no source mapping, so they are set to transparent. This is the standard fisheye crop.

What is the output format? The download is a PNG file with transparency support, preserving the fisheye crop.

Does this tool upload my images? No. All processing happens locally in your browser. Your image never leaves your device.