¤ 1. Run detect,
Mark's corner detector
|
| INPUT: |
an image of the calibration aid |
| OUTPUT: |
a DAT file detailing corners detected in the image and their strengths |
| See sample output |
|
¤ 2. Run analyze,
Mark's data extrapolator, which takes detect's output
and figures out equivalent data for infinitesimal window sizes, attempting to place corners with
sub-pixel accuracy (this is a large task, seeing as how images don't have sub-pixel accuracy!)
|
| INPUT: |
eight data files, output from detect,
giving information for all eight images of the calibration aid
a flag telling whether we want information for the xy-plane or the z-axis |
| OUTPUT: |
a DAT file detailing all corners from the images in either the
xy-plane or the z-axis |
| See sample output |
|
|
¤ 3. Run the Linux scripts
tail +2 IMAGENUM_w0s3.dat | awk '{ print $1, $2 }' > IMAGENUM_0.dat
and
tail +2 IMAGENUM_wZs3.dat | awk '{ print $1, $2 }' > IMAGENUM_Z.dat
to write just the first two numbers from each data line of analyze's output files
to the data files that will be sent to Zhang's easycalib program
|
|
• see the man
entry for tail
• see the man
entry for awk
|
| INPUT: |
a data file with five numbers per line |
| OUTPUT: |
a data file with just the essential information--the x- and y-coordinates
in the image for each corner detected--written per line |
| See sample output |
|
¤ 4. call
Zhengyou Zhang's camera calibration program
for Windows, easycalib.exe, to convert these files to data
for the combined set of eight images, giving camera parameter information
|
|
| INPUT: |
one data file, in the format produced by Step 3, for each of a minimum of eight
(and in this case exactly eight) images taken by the camera to be calibrated |
| OUTPUT: |
one data file with information gathered from all the input files (in this case,
representing either the xy-plane or the z-axis |
| See sample output |
|
¤ 5. call zerror3d,
Mark's final statistic generator, to display output on the 2-D and 3-D statistics of the error
in the current routine (of course, only the error not generated by Zhang's calibrator matters
to us)
|
|
| INPUT: |
eight input files for eight images, containing only detected corner coordinates,
and the one output file produced by Zhang's program, containing either 2-D or 3-D calibration
information |
| OUTPUT: |
statistics on 2-D and 3-D average errors, given known point coordinates, of
corner coordinates generated from a camera with the internal parameters given by Zhang's
program's output |
| See sample output |