mrcal-cull-corners - Filters a corners.vnl on stdin to cut out some points
$ < corners.vnl mrcal-cull-corners --cull-left-of 1000 > corners.culled.vnlThis tool reads a set of corner detections on stdin, throws some of them out, and writes the result to stdout. This is useful for testing and evaluating the performance of the mrcal calibration tools.
The specific operation of this tool is defined on which --cull-... option is given. Exactly one is required:
--cull-left-of X: throw away all corner observations to the left of the given
X coordinate
--cull-rad-off-center D: throw away all corner observations further than D
away from the imager center. --imagersize must be given also so that we know
where the imager center is
--cull-random-observations-ratio R: throws away a ratio R object observations
at random. To throw out half of all object observations, pass R = 0.5.
--object-width-n and --object-height-n are then required to make the parsing
work--cull-left-of X and --cull-rad-off-center throw out individual points. This is done by keeping the point in the output data strem, but setting its decimation level to '-'. The downstream tools then know to ignore those points
--cull-random-observations-ratio throws out whole object observations, not just individual points. These removed observations do not appear in the output data stream at all
This tool exists primarily for testing, and probably you don't want to use it. The filtering is crude, and the tool might report chessboard observations with very few remaining points. You PROBABLY want to post-process the output to keep only observations with enough points. For instance:
mrcal-cull-corners ... > culled-raw.vnl
vnl-join --vnl-sort - -j filename culled-raw.vnl \
<(< culled-raw.vnl vnl-filter -p filename --has level |
vnl-uniq -c |
vnl-filter 'count > 20' -p filename ) \
> culled.vnl -h, --help show this help message and exit
--object-width-n OBJECT_WIDTH_N
How many points the calibration board has per
horizontal side. This is required if --cull-random-
observation-ratio
--object-height-n OBJECT_HEIGHT_N
How many points the calibration board has per vertical
side. If omitted, I assume a square object and use the
same value as --object-width-n
--imagersize IMAGERSIZE IMAGERSIZE
Size of the imager. This is required if --cull-rad-
off-center
--cull-left-of CULL_LEFT_OF
Throw out all observations with x < the given value.
Exclusive with the other --cull-... options
--cull-rad-off-center CULL_RAD_OFF_CENTER
Throw out all observations with dist_from_center > the
given value. Exclusive with the other --cull-...
options
--cull-random-observations-ratio CULL_RANDOM_OBSERVATIONS_RATIO
Throw out a random number of board observations. The
ratio of observations is given as the argument. 1.0 =
throw out ALL the observations; 0.0 = throw out NONE
of the observations. Exclusive with the other
--cull-... optionshttps://www.github.com/dkogan/mrcal
Dima Kogan, <dima@secretsauce.net>
Copyright (c) 2017-2020 California Institute of Technology ("Caltech"). U.S. Government sponsorship acknowledged. All rights reserved.
Licensed under the Apache License, Version 2.0 (the "License"); You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0