Monte Carlo ray tracing library librat

Prof. P. Lewis, UCL Geography
To download and install, download and run this configure script. It should work on any unix-like operating system (tested on Solaris, various linux, Mac OS X, etc.).

Example 3D animations
This page contains a series of animations of both reflectance and lidar simulations, as animated gifs (large) and QT movies (smaller).


References
Recent PhD and Msc theses
Adams, J. (2013) Empirically testing the use of Directional Area Scattering Factor (DASF) to correct hyperspectral remote sensing data for canopy structural effects, MSc thesis, Univ. of London (PDF).
Hitchins, A. (2013) Radiative Transfer modelling of wild fire in African savannah systems, MSc thesis, Univ. of London (PDF).
Origo, N. (2012) Reconstructing 3D tree structure from terrestrial waveform LiDAR data, MSc thesis, Univ. of London (PDF).
Fleming, S. (2012) Simulating the uncertainty sensitivity to vertical resolution of airborne LiDAR for tropical forest biomass estimation, MSc thesis, Univ. of London (PDF).
Ireland, L. (2011) Estimating biomass of mountain birch in Fennoscandia using discrete return airborne lidar, MSc thesis, Univ. of London (PDF).
Grundy, B. (2011) A 3D simulation study of the potential of full waveform lidar to detect and quantify tropical forest degradation in Madgascar, MSc thesis, Univ. of London (PDF).
Hancock, H. (2010) Understanding the measurements of forests with waveform lidar, PhD thesis, UCL Geography (PDF).
Calders, K. (2010) Modelling lidar waveforms to solve for canopy properties, MSc thesis, Univ. of London (PDF).
Kalogirou, V. (2006) Simulation of discrete-return lidar signal from conifer stands for forestry applications, MSc thesis, Univ. of London (PDF).
Heyder, U. (2005) Vertical Forest Structure from ICESat/GLAS Lidar data, MSc thesis, Univ. of London (PDF).

Journal and conf. papers
Widlowski, JL, Pinty, B, M Lopatka, C Atzberger, D Buzica, M Chelle, M. I. Disney, JP Gastellu-Etchegorry, M Gerboles, N Gobron, E Grau, H Huang, A Kallel, H Kobayashi, P Lewis, M Schlerf, J Stuckens, W Qin, D Xie (2013) The 4th Radiation Transfer Model Intercomparison (RAMI-IV): Using ISO standards to evaluate model proficiency, JGR Atmospheres, 118, 6869-6890, doi:10.1002/jgrd.50497 (PDF).
Calders, K., Lewis, P., Disney, M. I., Verbesselt, J. and Herold, M. (2013) Modelling LiDAR waveforms to solve for canopy properties, Rem. Sens. Environ., 134, 39-49, doi: 10.1016/j.rse.2013.02.018 (PDF).
Raumonen, P, Kaasalainen, M, ┼kerblom, M, Kaasalainen, S, Kaartinen, H, Vastaranta, M, Holopainen, M, Disney, M. I. and Lewis, P (2013) Comprehensive Quantitative Tree Models From Terrestrial Laser Scanner Data, Remote Sensing, 5(2), 491-520; doi:10.3390/rs5020491. (Direct link to free access).
Hancock, S., Lewis, P., Foster, M., Disney, M. I., and Muller, J. -P. (2012) Measuring tree height over topography and understory vegetation with dual wavelength lidar: a simulation study, Agric. For. Meteorol. Agric. For. Meteorol., 161, 123-133. (PDF).
Hancock, S., Disney, M. I., Muller, J. -P., Lewis, P. and Foster, M., (2011) A threshold insensitive method for locating tree tops with waveform lidar, Rem. Sens. Environ., 115 (12) 3286-3297, doi:10.1016/j.rse.2011.07.012, doi:10.1016/j.rse.2011.07.012 (PDF).
Disney, M. I., Lewis, P., Gomez-Dans, J., Roy, D., Wooster, M. and Lajas, D. (2011) 3D radiative transfer modelling of fire impacts on a two-layer savanna system, submitted Rem. Sens. Environ., 115, 1886-1881 (PDF).
Disney, M. I., Kalogirou, V., Lewis, P. E., Prieto-Blanco, A., Hancock, S. and Pfeifer, M. (2010) Simulating the impact of discrete-return lidar system and survey characteristics over 2 young conifer and broadleaf forests, Remote Sensing Environment, 114, 1546-1560, doi:10.1016/j.rse.2010.02.009 (PDF).
M. Disney, P. Lewis M. Bouvet, Prieto-Blanco, A. and Hancock, S. (2009) Quantifying surface reflectivity for spaceborne lidar via two independent methods, IEEE Trans. Geosci. Rem. Sens., 47(10), 3262-3271, doi: 10.1109/TGRS.2009.2019268 (PDF).
J.-L. Widlowski, M. Robustelli, M. Disney, J.-P. Gastellu-Etchegorry, T. Lavergne, P. Lewis, P. R. J. North, B. Pinty, R. Thompson, M. M. Verstraete, (2008) The RAMI On-line model checker (ROMC): A web-based benchmarking facility for canopy reflectance models, Remote Sensing of Environment, 112(3), 1144-1150 (PDF).
J-L. Widlowski, M. Taberner, B. Pinty, V. Bruniquel-Pinel, M. Disney, R. Fernandes, J-P. Gastellu-Etchegorry, N. Gobron, A. Kuusk, T. Lavergne, S. Leblanc, P. E. Lewis, E. Martin, M. Mottus, P. R. J. North, W. Qin, M. Robustelli, N. Rochdi, R. Ruiloba, C. Soler, R. Thompson, W. Verhoef, M. M. Verstraete, D. Xie, (2007), The third RAdiation transfer Model Intercomparison (RAMI) exercise: Documenting progress in canopy reflectance models, Journal of Geophysical Research, 112, D09111, doi:10.1029/2006JD007821.

  • M. Disney, P. Lewis, P. Saich (2006) 3D modelling of forest canopy structure for remote sensing simulations in the optical and microwave domains, Remote Sensing of Environment. Rem. Sens. Environ., 100(1), 114-132. (doi:10.1016/j.rse.2005.10.003, PDF)
  • Pinty, B.; Widlowski, J.-L.; Taberner, M.; Gobron, N.; Verstraete, M. M.; Disney, M.; Gascon, F.; Gastellu, J.-P.; Jiang, L.; Kuusk, A.; Lewis, P.; Li, X.; Ni-Meister, W.; Nilson, T.; North, P.; Qin, W.; Su, L.; Tang, S.; Thompson, R.; Verhoef, W.; Wang, H.; Wang, J.; Yan, G.; Zang, H. (2004) Radiation Transfer Model Intercomparison (RAMI) exercise: Results from the second phase  J. Geophys. Res., Vol. 109, No. D6, D06210 10.1029/2003JD004252 25 March 2004(PDF) [Google Scholar: cited by 5]
  • M.I. Disney, P. Lewis, and P. North (2000) Monte Carlo ray tracing in optical canopy reflectance modelling.  Remote Sensing Reviews, 18:163-196.[Google Scholar: cited by 13]
  • P. Lewis , (1999) The Botanical Plant Modelling System.Agronomie: Agriculture and Environment Vol.19, No.3-4, pp.185-210 [Google Scholar: cited by 22]
  • A.J. McDonald, F. Gemmel, and P. Lewis , (1998) Investigation of the utility of spectral vegetation indices for determining information on coniferous forests. Remote Sensing of Environment 66(3), 250-272.[Google Scholar: cited by 23]
  • S. Liang, P. Lewis , R. Dubayah, W. Qin, and D. Shirey (1997) Topographic Effects on Surface Bidirectional Reflectance Scaling, Journal of Remote Sensing Vol. 1 (ISSN 1007-4619) 82-93.
  • Estimating Land Surface Albedo in the HAPEX-Sahel Southern Super-Site: Inversion of Two BRDF Models against Multiple Angle ASAS Images. Journal of Hydrology. 188-189, pp. 749-778[Google Scholar: cited by 6]
  • D.W. Burgess, P. Lewis and J-P. Muller (1995), Topographic Effects in AVHRR NDVI Data. Remote Sens. Environ, 54, 223-232.[Google Scholar: cited by 11]
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  • P. Saich, P. Lewis, M. Disney, P. van Oevelen, I. Woodhouse, B. Andrieu, C. Fournier & S. Ljutovac (2003), Development of Architectural Vegetation Growth Models for Remote Sensing Applications", ESA Report contract 14940.
  • Final report of ESA project "Estimating surface lidar reflectivity for A-SCOPE", M. I. Disney and P. Lewis, ESA RFQ/3-12259/07/NL/JA.
  • Disney, M. I., Lewis, P. and Bouvet, M. (2008) Quantifying surface reflectivity for spaceborne lidar missions, in proc. IGARSS'08, 5-11 July, Boston, USA, 2008.
  • S. Hancock, Disney, M. I., P. Lewis, J.-P. Muller (2008) Exploring the measurement of forests with full waveform lidar through Monte-Carlo ray tracing, in proc. IGARSS'08, 5-11 July, Boston, USA, 2008.
  • Hancock, S., Lewis, P., Disney, M. I., Foster, M. and Muller, J. -P. (2008) Assessing the accuracy of forest height estimation with long pulse waveform lidar through Monte-Carlo ray tracing, in proc. SilviLaser 8th International Conference on LIDAR applications, 17-19 September, Edinburgh.
  • Disney, M. I. and Lewis, P. (2007) Spectral invariant behaviour of a complex 3D forest canopy, in proc. 10th ISPMSRS meeting, Davos, Switzerland, 12-14 March 2007.
  • Pfeifer, M., Disney, M. I. and Lewis, P. (2007) Simulating gap fraction of complex forest scenes, in proc. 10th ISPMSRS meeting, Davos, Switzerland, 12-14 March 2007.
  • Lewis, P. and Disney, M. I. (2007) Modelling Canopy reflectance with spectral invariants, in proc. 10th ISPMSRS meeting, Davos, Switzerland, 12-14 March 2007.
  • Hancock, S., Lewis, P., Muller, J. P and Disney, M. I. (2007) Using Monte Carlo ray tracing to investigate the measurement of forest parameters with the Echidna laser scanner, in proc. 10th ISPMSRS meeting, Davos, Switzerland, 12-14 March 2007.
  • P. Lewis, J. Hillier, J. Watt, B. Andrieu, C. Fournier, P. Saich, M. Disney, (2005) 3D dynamic vegetation modelling of wheat for remote sensing simulation and inversion, Proc. 9th Intl. Symp. on Physical Measurements and Signatures in Remote Sensing, Beijing, China, 17-19 Oct 2005 144-146
  • M. Disney, P. Lewis, T. Quaife, C. Nichol, (2005) A spectral invariant approach to modelling canopy and leaf scattering, Proc. 9th Intl. Symp. on Physical Measurements and Signatures in Remote Sensing, Beijing, China, 17-19 Oct 2005 318-320
  • Lewis et al. 3D plant modelling for remote sensing simulation, Workshop on 3D modelling in EO, Avignon, France, March 2004
  • M. Disney, P. Lewis and P. Saich (2004) 3D modelling of forest canopy structure for remote sensing simulation and parameter estimation, in proc. 4th International Workshop on Functional-Structural Plant Models, CIRAD, Montpellier, June 7-11, 2004, p 282.
  • P.Lewis, P.Saich, M. Disney, B. Andrieu, C. Fournier, T. Macklin and J. Bodley (2004) Calibration of an L-system model of winter wheat for remote sensing modelling and inversion, in proc. 4th International Workshop on Functional-Structural Plant Models, CIRAD, Montpellier, June 7-11, 2004, pp 257-261.
  • P. Lewis, P. Saich, J. Hillier, M. Disney. B. Andrieu, C. Fournier, (2004),Estimation of Wheat Biophysical Parameters by Inverting Remote Sensing Data using 3D Models of Plant Dynamics at Optical and Microwave Wavelengths, plant modelling workshop, Halle, germany, Feb. 2004
  • P. Lewis, P. Saich, M. Disney, B. Andrieu, C. Fournier, (2003) Modelling the radiometric response of a dynamic, 3D structural model of wheat in the optical and microwave domains. Proc. IEEE Geosci. and Rem. Sens. Symp. IGARSS'03 (Toulouse) Volume 6,  21-25 July 2003 Page(s):3543 - 3545 vol.6
  • M. Disney, P. Saich P. Lewis, Modelling the radiometric response of a dynamic, 3D structural model of Scots Pine in the optical and microwave domains. Proc. IEEE Geosci. and Rem. Sens. Symp. IGARSS'03 (Toulouse) Volume 6,  21-25 July 2003 Page(s):3537 - 3539 vol.6
  • P. Saich, P. Lewis, M. Disney (2003) Biophysical parameter retrieval from forest and crop canopies in the optical and microwave domains using 3D models of canopy structure. Proc. IEEE Geosci. and Rem. Sens. Symp. IGARSS'03 (Toulouse) Volume 6,  21-25 July 2003 Page(s):3546 - 3548 vol.6
  • P. Saich, P. Lewis, M. Disney and G. Thackrah, 2001. Comparison of Hymap/E-SAR data with models for optical reflectance and microwave scattering from vegetation canopies, in proc. Third International Workshop on Retrieval of Bio-and Geo-Physical Parameters from SAR data for Land Applications, Sheffield, September 2001.
  • P. Lewis(1999) The Botanical Plant Modelling System: a model for remote sensing simulation studies. XVI International Botanical Congress, 1-7 August 1999. Saint Louis, Missouri, USA.
  • P. Lewis  and M. Disney (1999) Application of the Botanical Plant Modelling System (BPMS) to the analysis of spatial information in remotely sensed imagery , in proceedings of 25th Annual Remote Sensing Society Conference , 7-10th September 1999, Cardiff, UK. 507-514.
  • P. Lewis and M. Disney, (1998) The Botanical Plant Modelling System (BPMS): a case study of multiple scattering in a barley canopy. IGARSS'98, Seattle, USA Volume 3,  6-10 July 1998 Page(s):1481 - 1483 vol.3
  • M. Disney and P. Lewis . (1998) An investigation of how linear BRDF models deal with the complex scattering processes encountered in a real canopy, Proc. IGARSS '98, Jul. 6th-10th, Seattle, USA. Volume 3,  6-10 July 1998 Page(s):1231 - 1233 vol.3
  • M. Disney, P. Lewis . , Knott, R., Hobson, Evans-Jones, K. and Barnsley, M. J. (1998) Validation of a manual measurement method for deriving 3D canopy structure using the bpms, Proc. IGARSS '98, Jul. 6th-10th, Seattle, USA. Volume 3,  6-10 July 1998 Page(s):1249 - 1251 vol.3
  • N. Akkal, P. Boissard, C. Chabanet, M.H. Jeuffroy, P. Lewis , and J.M. Meynard(1997), Nitrogen fertilization management in winter wheat based on early estimate of the cover fraction. 1st European Conf. on Precision Agriculture, Warwick University (U.K.), 7-10 Sept. 97, Vol 1. 405-412, BIOS Scientific Publishers
  • P. Lewis and P. Boissard, (1997), The use of 3D plant modelling and measurement in remote sensing, 7th International Symposium Physical Measurements and Signatures in Remote Sensing, Courchevel, France, April 7-11, 1997. Vol. 1. pp 319-326. (ISBN 90 5410 9173)
  • P. Boissard, P. Valery, N. Akkal, J. Helbert, and P. Lewis (1997), Paremetrisation d'un modele architectural de ble au cours du tallage. Estimation des parametres de structure par photogrammetrie. Actes du Seminaire sur la Modelisation ArchitecturaleINRA Paris, 10-12 Mars 1997, 213-222
  • P. Lewis (1997), The Botanical Plant Modelling System (B.P.M.S.). Actes du Seminaire sur la Modelisation ArchitecturaleINRA Paris, 10-12 Mars 1997, 45-54
  • P. Lewis and M. Disney, (1997), Examining BRDF model operation with the botanical plant modelling system, Proc. Remote Sensing Society Conference, Reading, 1997. pp. 298-303.
  • P. Boissard, N. Akkal, P. Lewis , (1996), 3D Plant Modelling in Agronomy. Association of Applied Biologists: Modelling in Applied Biology: Spatial Aspects, 24/27 June 1996, Brunel, U.K.
  • P. Boissard, N. Akkal, P. Lewis , P. Valery, and J-M Meynard, (1995), Linking a 3D Plant Model Database of Crop Structure to Models of Canopy Development. Int. Colloq. Photosynthesis and Remote Sensing, 28-31 Aug. 1995, Montpellier, Fr.
  • P. Lewis and P. Boissard, (1995), A Botanical Plant Modelling System: a Model for Deriving and Describing Plant Form and Simulating the Canopy Shortwave Radiation Regime. Invited Paper (abstract only in proc.) RSS Meeting: "The Interaction of Vegetation Canopies with Radiation", Sheffield CEOS, May 24, 1995.
  • D.W. Burgess and P. Lewis , (1994), The Topographic Effect on NDVI Measurements Derived from AVHRR Data, 7th Australaisian Remote Sensing Conference, 1-4 March 1994, Melbourne, Australia, 189-196.
  • P. Lewis and J-P. Muller , (1992), The Advanced RAdiometric RAy Tracer: ARARAT for Plant Canopy Reflectance Simulation, International Arch. Photogrammetry and Remote Sensing, XXIX, Comm. VII(B7), 26-34.
  • P. Lewis , J-P. Muller and K. Morris, (1991), Quality Assessment of a Botanical Plant Modelling System for Remote Sensing Simulation Studies, Proc. IGARSS'91, Espoo, Finland, June 3-6th, 1917-1920.
  • P. Lewis and J-P. Muller , (1990), Botanical Plant Modelling for Remote Sensing Simualtion Studies, Proc IGARSS'90, Washington D.C., USA, 1739-1782.