Docs for ‘QGIS testing’. Visit http://docs.qgis.org/2.18 for QGIS 2.18 docs and translations.

Imagery segmentation

Grid skeletonization

Description

<put algorithm description here>

Parameters

Grid [raster]
<put parameter description here>
Method [selection]

<put parameter description here>

Options:

  • 0 — [0] Standard
  • 1 — [1] Hilditch’s Algorithm
  • 2 — [2] Channel Skeleton

Default: 0

Initialisation [selection]

<put parameter description here>

Options:

  • 0 — [0] Less than
  • 1 — [1] Greater than

Default: 0

Threshold (Init.) [number]

<put parameter description here>

Default: 0.0

Convergence [number]

<put parameter description here>

Default: 3.0

Outputs

Skeleton [raster]
<put output description here>
Skeleton [vector]
<put output description here>

Console usage

processing.runalg('saga:gridskeletonization', input, method, init_method, init_threshold, convergence, result, vector)

See also

Seed generation

Description

<put algorithm description here>

Parameters

Features [multipleinput: rasters]
<put parameter description here>
Bandwidth (Cells) [number]

<put parameter description here>

Default: 2

Type of Surface [selection]

<put parameter description here>

Options:

  • 0 — [0] smoothed surface
  • 1 — [1] variance (a)
  • 2 — [2] variance (b)

Default: 0

Extraction of... [selection]

<put parameter description here>

Options:

  • 0 — [0] minima
  • 1 — [1] maxima
  • 2 — [2] minima and maxima

Default: 0

Feature Aggregation [selection]

<put parameter description here>

Options:

  • 0 — [0] additive
  • 1 — [1] multiplicative

Default: 0

Normalized [boolean]

<put parameter description here>

Default: True

Outputs

Surface [raster]
<put output description here>
Seeds Grid [raster]
<put output description here>
Seeds [vector]
<put output description here>

Console usage

processing.runalg('saga:seedgeneration', grids, factor, type_surface, type_seeds, type_merge, normalize, surface, seeds_grid, seeds)

See also

Simple region growing

Description

<put algorithm description here>

Parameters

Seeds [raster]
<put parameter description here>
Features [multipleinput: rasters]
<put parameter description here>
Method [selection]

<put parameter description here>

Options:

  • 0 — [0] feature space and position
  • 1 — [1] feature space

Default: 0

Neighbourhood [selection]

<put parameter description here>

Options:

  • 0 — [0] 4 (von Neumann)
  • 1 — [1] 8 (Moore)

Default: 0

Variance in Feature Space [number]

<put parameter description here>

Default: 1.0

Variance in Position Space [number]

<put parameter description here>

Default: 1.0

Threshold - Similarity [number]

<put parameter description here>

Default: 0.0

Refresh [boolean]

<put parameter description here>

Default: True

Leaf Size (for Speed Optimisation) [number]

<put parameter description here>

Default: 256

Outputs

Segments [raster]
<put output description here>
Similarity [raster]
<put output description here>
Seeds [table]
<put output description here>

Console usage

processing.runalg('saga:simpleregiongrowing', seeds, features, method, neighbour, sig_1, sig_2, threshold, refresh, leafsize, segments, similarity, table)

See also

Watershed segmentation

Description

<put algorithm description here>

Parameters

Grid [raster]
<put parameter description here>
Output [selection]

<put parameter description here>

Options:

  • 0 — [0] Seed Value
  • 1 — [1] Segment ID

Default: 0

Method [selection]

<put parameter description here>

Options:

  • 0 — [0] Minima
  • 1 — [1] Maxima

Default: 0

Join Segments based on Threshold Value [selection]

<put parameter description here>

Options:

  • 0 — [0] do not join
  • 1 — [1] seed to saddle difference
  • 2 — [2] seeds difference

Default: 0

Threshold [number]

<put parameter description here>

Default: 0

Allow Edge Pixels to be Seeds [boolean]

<put parameter description here>

Default: True

Borders [boolean]

<put parameter description here>

Default: True

Outputs

Segments [raster]
<put output description here>
Seed Points [vector]
<put output description here>
Borders [raster]
<put output description here>

Console usage

processing.runalg('saga:watershedsegmentation', grid, output, down, join, threshold, edge, bborders, segments, seeds, borders)

See also