@article{fdi:010053350,
  title = {{B}idirectional texture function of high resolution optical images of tropical forest : an approach using {L}i{DAR} hillshade simulations},
  author = {{B}arbier, {N}icolas and {P}roisy, {C}hristophe and {V}{\'e}ga, {C}. and {S}abatier, {D}aniel and {C}outeron, {P}ierre},
  editor = {},
  language = {{ENG}},
  abstract = {{Q}uantifying and monitoring the structure and degradation of tropical forests over regional to global scales is gaining increasing scientific and societal importance. {R}eliable automated methods are only beginning to appear; for instance, through the recent development of textural approaches applied to high resolution optical imagery. {I}n particular, the {F}ourier {T}ransform {T}extural {O}rdination ({FOTO}) method shows some potential to provide non-saturating estimates of tropical forest structure, including for large scale applications. {H}owever, we need to understand more precisely how canopy structure interacts with physical signals (light) to produce a given texture, notably to assess the method's sensitivity to varying sun-view acquisition conditions. {I}n this study, we take advantage of the detailed description of canopy topography provided by airborne small footprint {L}i{DAR} data acquired over the {P}aracou forest experimental station in {F}rench {G}uiana. {U}sing hillshade models and a range of sun-view angles identical to the actual parameter distributions found for {Q}uickbird ({TM}) images over the {A}mazon, we study noise and bias in texture estimation induced by the changing configurations. {W}e introduce the bidirectional texture function, which summarizes these effects, and in particular the existence of a textural 'hot spot', similar to a well-known feature of bidirectional reflectance studies. {F}or texture, this effect implies that coarseness decreases in configurations for which shadows are concealed to the observer. {W}e also propose a method, termed partitioned standardization, that allows mitigating acquisition effects and discuss the potential for an operational use of {VHR} optical imagery and the {FOTO} method in the current context of international decisions to reduce {CO}2 emissions due to deforestation and forest degradation.},
  keywords = {{T}ropical forests ; {C}anopy structure ; {S}mall footprint {L}i{DAR} ; {F}ourier ; transform ; {T}exture ; {F}rench {G}uiana ; {P}aracou station ; {S}un-view angles ; {B}idirectional texture function},
  booktitle = {},
  journal = {{R}emote {S}ensing of {E}nvironment},
  volume = {115},
  numero = {1},
  pages = {167--179},
  ISSN = {0034-4257},
  year = {2011},
  DOI = {10.1016/j.rse.2010.08.015},
  URL = {https://www.documentation.ird.fr/hor/fdi:010053350},
}