TCA_CORRECT(1) HUGIN TCA_CORRECT(1)NAME
tca_correct - Calculate transverse chromatic aberration
SYNOPSIS
tca_correct [options] inputfile
<inputfile> is the base name of 4 image files:
<inputfile>
Colour file to compute TCA parameters
red_<inputfile>
Red channel of <inputfile>
green_<inputfile>
Green channel of <inputfile>
blue_<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
DESCRIPTION
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.
OPTIONS -h Display help
-l input file is PTO file instead of image
-m method
optimization method (0 normal, 1 newfit)
-o optvars
string of variables to optimize ("abcvde")
-r 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)
-v Verbose
-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
AUTHORS
Written by Pablo d'Angelo and others.
"Version: 2011.4.0" 2011-12-02 TCA_CORRECT(1)
Check Out this Related Man Page
FULLA(1) HUGIN FULLA(1)NAME
fulla - Correct lens distortion, vignetting and chromatic aberration
SYNOPSIS
fulla [options] inputfile(s)
DESCRIPTION
Apply radial or flat-field vignetting correction as well as geometrical radial distortion and transversal chromatic aberration correction.
fulla can be used to batch correct a large number of files. Radial distortion coefficients can be read from a PTLens database (only
database version 4.2 is supported).
Vignetting correction is done the same way as described in the nona script file documentation. Vignetting correction can be done based on
a flat-field or a radial scaling.
Vignetting correction by flat-field division:
I = I / c, c = flat-field / mean(flat-field)
Radial vignetting correction:
I = I / c, c = a + b*r^2 + c*r^4 + d*r^6
The radial distortion correction is identical to the one implemented by PanoTools:
r_new = a*r^4 + b*r^3 + c*r^2 + d*r [1]
Since transversal chromatic aberrations (TCA) leads to differently scaled objects in the red, green and blue channel, it can be corrected
by scaling the red and blue channel so that they match the green channel. Most applications, like Photoshop or Picture Window Pro offer TCA
correction by linear scaling. This is equal to varying the d parameter in equation [1].
See http://hugin.sf.net/tutorials/tca for a method to determine these parameters.
OPTIONS -g a:b:c:d
Radial distortion coefficient for all channels, (a, b, c, d)
-b a:b:c:d
Radial distortion coefficients for blue channel, (a, b, c, d). This is applied on top of the -g distortion coefficients, use for TCA
corr
-r a:b:c:d
Radial distortion coefficients for red channel, (a, b, c, d). This is applied on top of the -g distortion coefficients, use for TCA
corr
-p Try to read radial distortion coefficients (usually supplied using -g) from the PTLens database. The environment variable
PTLENS_PROFILE should point to the profile.txt file. Since newer version of the PTLens database are incompatible with fulla, download
the PTLens database from the hugin sourceforge website instead: http://www.sf.net/projects/hugin
-m Canon
Camera manufacturer, for PTLens database query. EXIF data inside JPEG files is read, if this option is not given
-n Camera
Camera name, for PTLens database query. EXIF data inside JPEG files is read, if this option is not given.
-l Lens
Lens name, for PTLens database query if not specified, a list of possible lenses is displayed
-d 50
Specify focal length in mm, for PTLens database query. EXIF data inside JPEG files is read, if this option is not given.
-s Do not rescale the image to avoid black borders.
-f filename
Vignetting correction by flat-field division
I = I / c, c = flat-field / mean(flat-field)
-c a:b:c:d
Radial vignetting correction by division:
I = I / c, c = a + b*r^2 + c*r^4 + d*r^6
-i value
Gamma of input data. used for gamma correction before and after flat-field correction
-t n
Number of threads that should be used during processing
-h Display help summary.
-o name
Set output filename. If more than one image is given, the name will be uses as suffix (default suffix: _corr)
-e value
Compression of the output files
For JPEG output: 0-100
For tiff output: DEFLATE, LZW
-v Verbose
AUTHORS
Written by Pablo d'Angelo. Also contains contributions from Douglas Wilkins, Ippei Ukai, Ed Halley, Bruno Postle, Gerry Patterson and Brent
Townshend.
This man page was written by Cyril Brulebois <cyril.brulebois@enst-bretagne.fr> and is licensed under the same terms as the hugin package
itself.
"Version: 2011.4.0" 2011-12-02 FULLA(1)