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Joint Demosaicking & Chromatic Aberration Correction

Chromatic Aberration destructively interferes with demosaicking algorithms to generate severe artifacts. Correcting CA after demosaicking combats the color fringing caused by the CA but not the demosaicking artifacts induced by it.

Correcting CA before demosaicking helps, but cannot be accomplished accurately. This is because each color plane of the mosaicked image is subsampled, and therefore, cannot be accurately resampled.

The IA Solution

Joint Demosaicking and Chromatic Aberration Correction solves the problem by building the CA model into the demosaicking process itself.

Correct CA

Drag the yellow magnifier to zoom into your region of interest. Or download the image set and use your own viewer.

Fine Print

Observe the fine print on the circular scale at 2x magnification. Artifacts are greatly reduced and legibility greatly improved.

Moire

Note the graduations on the circular scale. Large area regular patterns are greatly reduced.

Directional Errors

Observe the horizontal stripes filling the "Pure Brewed Lager Beer" caption at 2x magnification. There are no directional errors marring the clean, solid look.

Robustness

While existing raw converters can excel at certain feature types, they also have severe weaknesses elsewhere. IA's Joint Demosaicking and Chromatic Aberration Correction algorithm matches or surpasses all raw converters in nearly all feature types.

Image copyright Imaging Resource, taken with a Pentax K-01, available in raw format here. This image was selected for its high per-pixel sharpness and chromatic aberration.