tca_correct − Calculate transverse chromatic aberration


tca_correct [options] inputfile

<inputfile> is the base name of 4 image files:

Colour file to compute TCA parameters


Red channel of <inputfile>


Green channel of <inputfile>


Blue channel of <inputfile>

The channel images must be colour images with 3 identical channels. If any of −R, −G, or −B is given, this file name is used instead of the derived name.

Output: commandline arguments for fulla


Generates fulla command-line parameters for correction of transverse chromatic aberration ( TCA ) from sample photos. Ideal sample photos would have a lot of contrast over the entire image area, little saturated colour and no blown highlights.



Display help


input file is PTO file instead of image

−m method

optimization method (0 normal, 1 newfit)

−o optvars

string of variables to optimize ("abcvde")


Reset values (this will zero a,b,c,d,e params and set v to 10) makes sense only with −l option

−s <scale>

Scale for corner detection

−n <number>

number of points per grid cell (default: 10)

−g <number>

divide image in <number>x<number> grid cells (default: 10)

−t num

Remove all control points with an error higher than num pixels (default: 1.5)



−w filename

write PTO file

−R <r>

Use this file as red channel

−G <g>

Use this file as green channel

−B <b>

Use this file as blue channel


Written by Pablo d’Angelo and others.


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