AMC-analyse — automatic data capture from scans for AMC multiple choice exams.
auto-multiple-choice analyse --projet
project-dir [--seuil-coche threshold] [--tol-marque tol] [ --list-fichiers
files-list.txt | scan-files... ]
The AMC-analyse.pl command performs automatic
data capture from scans of completed answer sheets of an AMC multiple
choice questionnaire. Before calling
AMC_analyse.pl, AMC-prepare(1) should have been called to make working documents
(--mode s) and then MEP files (--mode
m).
--mep
project-mep-dirgives the directory where MEP files (prepared by AMC-prepare(1)) can be found.
--cr
project-cr-dirgives a directory where to create reports of the data capture.
--projet
project-dirWhen using this option, if --cr is not
used, project-cr-dir will be set to
project-dir/cr--mep is not used,
project-mep-dir will be set to
project-dir/mep
Giving the names of the scan files to process can be done in two ways:
these names can be given as arguments,
these names can be written to a plain file (one filename per
line), using the --list-fichiers
to give the
name of this file.files-list.txt
Some parameters for data capture may be set using the following options:
--seuil-coche
thresholdWhen deciding whether a box is checked or not,
AMC-analyse.pl compares the black ratio
(number of black pixels over total number of pixels) to
threshold. If the black ratio is
greater then threshold, the box is
declared to be checked. Standard values can be 0.15 in the
standard layout, or 0.5 for separate answer sheet layout (in
this last case, letters are drawn in the boxes, and the students
are told to fill the boxes entirely). The black ratio is written
in the data capture reports, so that this threshold value can be
refined later without calling AMC-analyse.pl
again.
--tol-marque
toldefines the tolerance when detecting the four marks in the
scans corners. These marks are detected looking for black
connected components which dimensions are
closed to the target dimension
target (exact dimensions of the marks
if printing/scanning process where perfectly acurate). If
tol is a real number, accepted
dimensions are those between
(1-tol)*target
and
(1+tol)*target.
If tol is
"tinf,tsup"
(where tinf and
tsup are real numbers), accepted
dimensions are those between
(1-tinf)*target
and
(1+tsup)*target.
A standard value is 0.2.
--debug
file.loggives a file to fill with debugging information.