Tool NameObject Based Image Segmentation
Tool IDobia
Library IDimagery_segmentation
Version1.0
Author(s)O.Conrad (c) 2014

Description

This Object Based Image Segmentation tool chain combines a number of tools for an easy derivation of geo-objects as polygons and is typically applied to satellite imagery. Segmentation is done using a 'Seeded Region Growing Algorithm'. Optionally the resulting polygons can be grouped by an unsupervised classification (k-means cluster analysis) or supervised classification (needs classified feature samples as additional input), both is performed on the basis of zonal feature grid statistics for each polygon object.

References

Adams, R. & Bischof, L. (1994): Seeded Region Growing. IEEE Transactions on Pattern Analysis and Machine Intelligence, Vol.16, No.6, p.641-647.

Bechtel, B., Ringeler, A. & Boehner, J. (2008): Segmentation for Object Extraction of Trees using MATLAB and SAGA. In: Boehner, J., Blaschke, T., Montanarella, L. [Eds.]: SAGA - Seconds Out. Hamburger Beitraege zur Physischen Geographie und Landschaftsoekologie, 19:59-70. online


Parameters

NameTypeIdentifierDescriptionConstraints
Input
Featuresgrid list, inputFEATURES
Training Samplestable, inputSAMPLESTraining samples for supervised classification. Provide a class identifier in the first field followed by sample data corresponding to the selected feature attributes
Output
Segmentsshapes, outputOBJECTS
Options
NormalizebooleanNORMALIZEDefault: 0
VerticeschoiceVERTICESAvailable Choices:
[0] cell corners
[1] smoothed cell corners
[2] cell edge centers
[3] cell edge center with less smoothed cell corners
[4] cell edge center with smoothed cell corners
Default: 0
Band Width for Seed Point Generationfloating point numberSEEDS_BAND_WIDTHIncrease band width to get less seed points.Default: 2.000000
NeighbourhoodchoiceRGA_NEIGHBOURAvailable Choices:
[0] 4 (Neumann)
[1] 8 (Moore)
Default: 0
DistancechoiceRGA_METHODAvailable Choices:
[0] feature space and position
[1] feature space
Default: 0
Variance in Feature Spacefloating point numberRGA_SIG_1Minimum: 0.000000
Default: 1.000000
Variance in Position Spacefloating point numberRGA_SIG_2Minimum: 0.000000
Default: 1.000000
Similarity Thresholdfloating point numberRGA_SIMILARITYMinimum: 0.000000
Default: 0.000000
Generalizationinteger numberMAJORITY_RADIUSApplies a majority filter with given search radius to the segments grid. Is skipped if set to zero.Default: 1
ClassificationchoiceCLASSIFICATIONAvailable Choices:
[0] none
[1] cluster analysis
[2] supervised classification
Default: 0
Split Distinct Polygon PartschoiceSPLIT_POLYGONSAvailable Choices:
[0] no
[1] yes
Default: 0
Number of Clustersinteger numberNCLUSTERDefault: 10
MethodchoiceCLASSIFIERAvailable Choices:
[0] Binary Encoding
[1] Parallelepiped
[2] Minimum Distance
[3] Mahalanobis Distance
[4] Maximum Likelihood
[5] Spectral Angle Mapping
Default: 0