NAME¶
opencv_haartraining - train classifier
SYNOPSIS¶
opencv_haartraining [options]
DESCRIPTION¶
opencv_haartraining is training the classifier. While it is running, you
can already get an impression, whether the classifier will be suitable or if
you need to improve the training set and/or parameters.
In the output:
- 'POS:'
- shows the hitrate in the set of training samples (should be equal or near
to 1.0 as in stage 0)
- 'NEG:'
- indicates the false alarm rate (should reach at least 5*10-6 to be
a usable classifier for real world applications)
If one of the above values gets
0 (
zero) there is an overflow. In
this case the false alarm rate is so low, that further training doesn't make
sense anymore, so it can be stopped.
OPTIONS¶
opencv_haartraining supports the following options:
- -data dir_name
- The directory in which the trained classifier is stored.
- -vec vec_file_name
- The file name of the positive samples file (e.g. created by the
opencv_createsamples(1) utility).
- -bg background_file_name
- The background description file (the negative sample set). It contains a
list of images into which randomly distorted versions of the object are
pasted for positive sample generation.
- -bg-vecfile
- This option is that bgfilename represents a vec file with discrete
negatives. The default is not set.
- -npos number_of_positive_samples
- The number of positive samples used in training of each classifier stage.
The default is 2000.
- -nneg number_of_negative_samples
- The number of negative samples used in training of each classifier stage.
The default is 2000.
Reasonable values are
-npos 7000 -nneg 3000.
- -nstages number_of_stage
- The number of stages to be trained. The default is 14.
- -nsplits number_of_splits
- Determine the weak classifier used in stage classifiers. If the value
is
- 1, then a simple stump classifier is used
- >=2, then CART classifier with number_of_splits internal
(split) nodes is used
- The default is 1.
- -mem memory_in_MB
- Available memory in MB for precalculation. The more memory you have
the faster the training process is. The default is 200.
- -sym, -nonsym
- Specify whether the object class under training has vertical symmetry or
not. Vertical symmetry speeds up training process and reduces memory
usage. For instance, frontal faces show off vertical symmetry. The default
is -sym.
- -minhitrate min_hit_rate
- The minimal desired hit rate for each stage classifier. Overall hit rate
may be estimated as min_hit_rate^number_of_stages. The default is
0.950000.
- -maxfalsealarm max_false_alarm_rate
- The maximal desired false alarm rate for each stage classifier. Overall
false alarm rate may be estimated as
max_false_alarm_rate^number_of_stages. The default is
0.500000.
- -weighttrimming weight_trimming
- Specifies whether and how much weight trimming should be used. The default
is 0.950000. A decent choice is 0.900000.
- -eqw
- Specify if initial weights of all samples will be equal.
- -mode
{BASIC|CORE|ALL}
- Select the type of haar features set used in training. BASIC uses
only upright features, while CORE uses the full upright feature set
and ALL uses the full set of upright and 45 degree rotated feature
set. The default is BASIC.
- For more information on this see http://www.lienhart.de/ICIP2002.pdf.
- -h sample_height
- The sample height (must have the same value as used during creation). The
default is 24.
- -w sample_width
- The sample width (must have the same value as used during creation). The
default is 24.
- -bt
{DAB|RAB|LB|GAB}
- The type of the applied boosting algorithm. You can choose between
Discrete AdaBoost ( DAB), Real AdaBoost (RAB), LogitBoost
(LB) and Gentle AdaBoost ( GAB). The default is GAB.
- -err
{misclass|gini|entropy}
- The type of used error if Discrete AdaBoost (-bt DAB) algorithm is
applied. The default is misclass.
- -maxtreesplits max_number_of_splits_in_tree_cascade
- The maximal number of splits in a tree cascade. The default is 0.
- -minpos min_number_of_positive_samples_per_cluster
- The minimal number of positive samples per cluster. The default is
500.
The same information is shown, if
opencv_haartraining is called without
any arguments/options.
EXAMPLES¶
TODO
SEE ALSO¶
opencv_createsamples(1),
opencv_performance(1)
More information and examples can be found in the OpenCV documentation.
AUTHORS¶
This manual page was written by
Daniel Leidert
<daniel.leidert@wgdd.de> and
Nobuhiro Iwamatsu
<iwamatsu@debian.org> for the Debian project (but may be used by
others).