classify_image_class_mlpclassify_image_class_mlpclassify_image_class_mlpClassifyImageClassMlpClassifyImageClassMlp (Operator)

Name

classify_image_class_mlpclassify_image_class_mlpclassify_image_class_mlpClassifyImageClassMlpClassifyImageClassMlp — Classify an image with a multilayer perceptron.

Signature

Description

classify_image_class_mlpclassify_image_class_mlpclassify_image_class_mlpClassifyImageClassMlpClassifyImageClassMlp performs a pixel classification with the multilayer perceptron (MLP) MLPHandleMLPHandleMLPHandleMLPHandleMLPHandle on the multichannel image ImageImageImageImageimage. Before calling classify_image_class_mlpclassify_image_class_mlpclassify_image_class_mlpClassifyImageClassMlpClassifyImageClassMlp the MLP must be trained with train_class_mlptrain_class_mlptrain_class_mlpTrainClassMlpTrainClassMlp. ImageImageImageImageimage must have NumInput channels, as specified with create_class_mlpcreate_class_mlpcreate_class_mlpCreateClassMlpCreateClassMlp. On output, ClassRegionsClassRegionsClassRegionsClassRegionsclassRegions contains NumOutput regions as the result of the classification. The parameter RejectionThresholdRejectionThresholdRejectionThresholdRejectionThresholdrejectionThreshold can be used to reject pixels that have an uncertain classification. RejectionThresholdRejectionThresholdRejectionThresholdRejectionThresholdrejectionThreshold represents a threshold on the probability measure returned by the classification (see classify_class_mlpclassify_class_mlpclassify_class_mlpClassifyClassMlpClassifyClassMlp and evaluate_class_mlpevaluate_class_mlpevaluate_class_mlpEvaluateClassMlpEvaluateClassMlp). All pixels having a probability below RejectionThresholdRejectionThresholdRejectionThresholdRejectionThresholdrejectionThreshold are not assigned to any class. Because an MLP typically assigns pixels that lie outside the convex hull of the training data in the feature space to one of the classes with high probability (confidence), it is useful in many cases to explicitly train a rejection class, even if RejectionThresholdRejectionThresholdRejectionThresholdRejectionThresholdrejectionThreshold is used, by adding samples for the rejection class with add_samples_image_class_mlpadd_samples_image_class_mlpadd_samples_image_class_mlpAddSamplesImageClassMlpAddSamplesImageClassMlp and by re-training the MLP with train_class_mlptrain_class_mlptrain_class_mlpTrainClassMlpTrainClassMlp.

Parallelization

• Multithreading type: reentrant (runs in parallel with non-exclusive operators).
• Multithreading scope: global (may be called from any thread).
• Automatically parallelized on internal data level.

Parameters

Example (HDevelop)

read_image (Image, 'ic')
gen_rectangle1 (Board, 80, 320, 110, 350)
gen_rectangle1 (Capacitor, 359, 263, 371, 302)
gen_rectangle1 (Resistor, 200, 252, 290, 256)
gen_rectangle1 (IC, 180, 135, 216, 165)
concat_obj (Board, Capacitor, Classes)
concat_obj (Classes, Resistor, Classes)
concat_obj (Classes, IC, Classes)
create_class_mlp (3, 3, 4, 'softmax', 'principal_components', 3, 42, \
                  MLPHandle)
add_samples_image_class_mlp (Image, Classes, MLPHandle)
get_sample_num_class_mlp (MLPHandle, NumSamples)
train_class_mlp (MLPHandle, 200, 1, 0.01, Error, ErrorLog)
classify_image_class_mlp (Image, ClassRegions, MLPHandle, 0.5)
dev_display (ClassRegions)
clear_class_mlp (MLPHandle)

Result

If the parameters are valid, the operator classify_image_class_mlpclassify_image_class_mlpclassify_image_class_mlpClassifyImageClassMlpClassifyImageClassMlp returns the value 2 (H_MSG_TRUE). If necessary an exception is raised.

Possible Predecessors

train_class_mlptrain_class_mlptrain_class_mlpTrainClassMlpTrainClassMlp, read_class_mlpread_class_mlpread_class_mlpReadClassMlpReadClassMlp

Alternatives

classify_image_class_svmclassify_image_class_svmclassify_image_class_svmClassifyImageClassSvmClassifyImageClassSvm, classify_image_class_gmmclassify_image_class_gmmclassify_image_class_gmmClassifyImageClassGmmClassifyImageClassGmm, classify_image_class_lutclassify_image_class_lutclassify_image_class_lutClassifyImageClassLutClassifyImageClassLut, class_ndim_boxclass_ndim_boxclass_ndim_boxClassNdimBoxClassNdimBox, class_ndim_normclass_ndim_normclass_ndim_normClassNdimNormClassNdimNorm, class_2dim_supclass_2dim_supclass_2dim_supClass2dimSupClass2dimSup

See also

add_samples_image_class_mlpadd_samples_image_class_mlpadd_samples_image_class_mlpAddSamplesImageClassMlpAddSamplesImageClassMlp, create_class_mlpcreate_class_mlpcreate_class_mlpCreateClassMlpCreateClassMlp

Module

Foundation