Polar Transforms
Convert images to polar or log-polar coordinates to unwrap circular structures and rotation-sensitive patterns.
Remap images between Cartesian and polar coordinate systems. Linear polar unwraps circular rings into horizontal bands. Log-polar maps are used in rotation/scale invariant recognition and simulates the human visual system's foveal representation.
How to Use Polar Transforms
- Upload an image: Upload one of the formats listed by the tool (JPG, PNG, WebP) and wait for the local preview.
- Adjust settings and process: Choose the transform direction (Cartesian to Polar or Polar to Cartesian) and select linear or log-polar mode.
- Review and download: Review the result, then download it in one of the formats offered by this tool.
Frequently asked questions
What is a polar transform?
A polar transform remaps image coordinates from Cartesian (x, y) to polar (radius, angle) space. Circular structures become horizontal lines, making it useful for analyzing rings, rotational symmetry, and camera calibration patterns.
What is log-polar?
Log-polar uses a logarithmic radial axis, compressing distant regions and expanding central ones. Similar to how the human retina and fovea process visual information. It enables scale and rotation invariant recognition.
When should I use log-polar instead of linear-polar?
Use log-polar when you need scale and rotation invariance. Scaling becomes a horizontal shift and rotation becomes vertical. This is useful for rotation-invariant template matching. Use linear-polar for simpler circular analysis like iris unwrapping or clock face reading.
Is the Polar Transforms tool free?
Yes. All tools on Pixlane are free with no signup required.
Does it reuse cached assets on repeat visits?
Browser caching can speed repeat visits; uncached site assets can still require an internet connection.
What image formats are supported?
JPG, PNG, and WebP are supported.
Can I convert back from polar to Cartesian coordinates?
Yes. Use the "From polar" direction setting to invert the transform. This reconstructs the original Cartesian layout from a polar-mapped image, useful for verifying the transform or undoing a previous conversion.
What is the center point for polar transformation?
By default the image center is used as the polar origin. All radial distances and angles are computed relative to this point. Moving the origin changes how circular structures map to horizontal lines in the output.