v.lidar.growing(1)

📦
version 8.4.2 · 8 versions
, in fedora 44

✨ v.lidar.growing ✨

okay bestie, gather round, because this is the manual page for v.lidar.growing from the GRASS GIS User's Manual (that's the v.lidar.growing(1) girlie herself 💅). She does Building contour determination and Region Growing algorithm for determining the building inside. no cap, that's literally the whole job.

KEYWORDS: vector, LIDAR 🛰️

🌸 SYNOPSIS 🌸

v.lidar.growing
v.lidar.growing --help
v.lidar.growing input=name output=name first=name  [tj=float]
[td=float]   [--overwrite]  [--help]  [--verbose]  [--quiet]  [--ui]

🎀 Flags

  • --overwrite — Allow output files to overwrite existing files (she will absolutely replace what's already there, so like… be aware 👀)
  • --help — Print usage summary
  • --verbose — Verbose module output (she talks a LOT)
  • --quiet — Quiet module output (she shuts up, respectfully)
  • --ui — Force launching GUI dialog

🦋 Parameters

  • input=name [required] — Name of input vector map. Input vector (v.lidar.edgedetection output) — so like, feed her the right snack pls.
  • output=name [required] — Name for output vector map
  • first=name [required] — Name of the first pulse vector map
  • tj=float — Threshold for cell object frequency in region growing. Default: 0.2
  • td=float — Threshold for double pulse in region growing. Default: 0.6

💖 DESCRIPTION 💖

okay so v.lidar.growing is the second of three steps to filter LiDAR data. the whole filter's goal is to recognize and extract attached and detached objects — think buildings, bridges, power lines, trees, etc. — so we can build a Digital Terrain Model. it's giving main character energy for the whole pipeline, honestly.

The modules identifies which is the internal area of every object on a LiDAR point surface. ✨

The classification categories from v.lidar.edgedetection are now rasterized. For each cell, it is evaluated if it (the cell) contains a point with double impulse (difference between the first and last pulse greater than a given threshold). 🫶

Starting from cells classified as OBJECT and with only one pulse all linked cells are selected and a convex hull algorithm is applied to them. Simultaneously, the mean of the corresponding heights (mean edge height) are computed.

Points inside the convex hull are classified as OBJECT if their height is greater than or equal to the previously mean computed edge height. This last step is done only in case of high planimetric resolution. 🔥

👑 NOTES 👑

The input data should be the output result of the v.lidar.edgedetection module. Otherwise, it goes to error! ⚠️ like, fr fr, do not skip that step.

The output of this module will be the input of v.lidar.correction module. The output will be a vector map which points are pre-classified as:

  • TERRAIN SINGLE PULSE (cat = 1, layer = 2)
  • TERRAIN DOUBLE PULSE (cat = 2, layer = 2)
  • OBJECT SINGLE PULSE (cat = 3, layer = 2)
  • OBJECT DOUBLE PULSE (cat = 4, layer = 2)

The final result of the whole procedure (v.lidar.edgedetection, v.lidar.growing, v.lidar.correction) will be a point classification in the same categories as above. 🎀

🌈 EXAMPLES 🌈

💅 Basic region growing procedure

v.lidar.growing input=edge output=growing first=firstpulse

📚 REFERENCES 📚

  • Antolin, R. et al., 2006. Digital terrain models determination by LiDAR technology: Po basin experimentation. Bolletino di Geodesia e Scienze Affini, anno LXV, n. 2, pp. 69-89.
  • Brovelli M. A., Cannata M., Longoni U.M., 2004. LIDAR Data Filtering and DTM Interpolation Within GRASS, Transactions in GIS, April 2004, vol. 8, iss. 2, pp. 155-174(20), Blackwell Publishing Ltd.
  • Brovelli M. A., Cannata M., 2004. Digital Terrain model reconstruction in urban areas from airborne laser scanning data: the method and an example for Pavia (Northern Italy). Computers and Geosciences 30 (2004) pp.325-331
  • Brovelli M. A. and Longoni U.M., 2003. Software per il filtraggio di dati LIDAR, Rivista dell?Agenzia del Territorio, n. 3-2003, pp. 11-22 (ISSN 1593-2192).
  • Brovelli M. A., Cannata M. and Longoni U.M., 2002. DTM LIDAR in area urbana, Bollettino SIFET N.2, pp. 7-26.
  • Performances of the filter can be seen in the ISPRS WG III/3 Comparison of Filters report by Sithole, G. and Vosselman, G., 2003.

🫶 SEE ALSO 🫶

v.lidar.edgedetection, v.lidar.correction, v.surf.bspline, v.surf.rst, v.in.pdal, v.in.ascii

the whole friend group, honestly. ✨

💜 AUTHORS 💜

Original version of program in GRASS 5.4: Maria Antonia Brovelli, Massimiliano Cannata, Ulisse Longoni and Mirko Reguzzoni

Update for GRASS 6.X: Roberto Antolin and Gonzalo Moreno

💻 SOURCE CODE 💻

Available at: v.lidar.growing source code (history)

Accessed: Saturday Jan 17 05:41:24 2026

Main index | Vector index | Topics index | Keywords index | Graphical index | Full index

okay that's the whole page, bestie, you ate 🍓 and now for the cute sign-off: this whole thing is © 2003-2025 GRASS Development Team, GRASS GIS 8.4.2 Reference Manual, running under GRASS 8.4.2, and this page was last touched Saturday Jan 17 05:41:24 2026. slay, go classify some pulses 💖✨

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