Herror ::combine_roads_xld (
Hobject EdgePolygons,
Hobject ModParallels,
Hobject ExtParallels,
Hobject CenterLines,
Hobject *RoadSides,
const HTuple &MaxAngleParallel,
const HTuple &MaxAngleColinear,
const HTuple &MaxDistanceParallel,
const HTuple &MaxDistanceColinear
)
HXLDPolyArray HXLDPolyArray::CombineRoadsXld (
const HXLDModParaArray &ModParallels,
const HXLDExtParaArray &ExtParallels,
const HXLDPolyArray &CenterLines,
const HTuple &MaxAngleParallel,
const HTuple &MaxAngleColinear,
const HTuple &MaxDistanceParallel,
const HTuple &MaxDistanceColinear
) const
Combine road hypotheses from two resolution levels.
::combine_roads_xld combines road hypotheses obtained from
two different resolution levels. The algorithm selects only those
hypotheses which mutually support each other in both resolution
levels. The parameters EdgePolygons,
ModParallels and ExtParallels correspond to
the road hypotheses from the highest resolution level. The
parameter CenterLines is the result of road extraction in
a lower resolution level. Those of the polygons EdgePolygons
are returned for which evidence of being roadsides is found in
both resolution levels. The parameters MaxAngleParallel
and MaxAngleColinear determine the angle, that may be formed
by two parallel collinear line segments, respectively. The
parameters MaxDistanceParallel and
MaxDistanceColinear determine the maximum allowed
distance of two parallel or colliear line segments, respectively.
The combination is done using a number of rules.
Parameters
EdgePolygons (input_object)
|
xld_poly-array -> Hobject: HXLDPolyArray
|
|
XLD polygons to be examined. |
ModParallels (input_object)
|
xld_mod_para-array -> Hobject: HXLDModParaArray
|
|
Modified parallels obtained from
EdgePolygons. |
ExtParallels (input_object)
|
xld_ext_para-array -> Hobject: HXLDExtParaArray
|
|
Extended parallels obtained from
EdgePolygons. |
CenterLines (input_object)
|
xld_poly-array -> Hobject: HXLDPolyArray
|
|
Road-center-line polygons to be examined. |
RoadSides (output_object)
|
xld_poly-array -> Hobject * : HXLDPolyArray
|
|
Roadsides found. |
MaxAngleParallel (input_control)
|
angle.rad -> HTuple.double / long
|
|
Maximum angle between two parallel line segments. |
|
Default value: 0.523598775598 |
|
Suggested values: 0.349065850399, 0.523598775598, 0.6981317008 |
|
Restriction: (0 <= MaxAngleParallel) <= (pi / 2) |
MaxAngleColinear (input_control)
|
angle.rad -> HTuple.double / long
|
|
Maximum angle between two collinear line segments. |
|
Default value: 0.261799387799 |
|
Suggested values: 0.174532925199, 0.261799387799, 0.349065850399 |
|
Restriction: (0 <= MaxAngleColinear) <= (pi / 2) |
MaxDistanceParallel (input_control)
|
real -> HTuple.double / long
|
|
Maximum distance between two parallel line segments. |
|
Default value: 40 |
|
Suggested values: 20, 30, 40, 50, 60 |
|
Restriction: MaxDistanceParallel > 0 |
MaxDistanceColinear (input_control)
|
real -> HTuple.double / long
|
|
Maximum distance between two collinear line segments. |
|
Default value: 40 |
|
Suggested values: 20, 30, 40, 50, 60 |
|
Restriction: MaxDistanceColinear > 0 |
Possible Predecessors
::mod_parallels_xld,
::gen_polygons_xld,
::affine_trans_contour_xld
Possible Successors
::get_polygon_xld,
::get_lines_xld
See also
::lines_gauss,
::lines_facet,
::get_channel_info,
::edges_sub_pix
References
C. Steger, C. Glock, W. Eckstein, H. Mayer, B. Radig; "Model-based
Road Extraction from Images"; in "Automatic Extraction of
Man-Made Objects from Aerial and Space Images"; A. Gruen,
O. Kuebler, P. Agouris (Editors); Birkhäuser Verlag (1995),
pp. 275-284.
C. Heipke, C. Steger, R. Multhammer; "A Hierarchical Approach to
Automatic Road Extraction from Aerial Imagery"; in "Integrating
Photogrammetric Techniques with Scene Analysis and Machine Vision
II"; D. M. McKeown, Jr., I. J. Dowman (Editors); Proc. SPIE 2486
(1995), pp. 222-231.
Module
Sub-pixel operators
Copyright © 1996-2002 MVTec Software GmbH