Research Article
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Year 2022, Volume: 4 Issue: 2, 45 - 52, 25.12.2022
https://doi.org/10.53093/mephoj.1176847

Abstract

References

  • Stock, K., & Guesgen, H. (2016). Geospatial reasoning with open data. In Automating open source intelligence (pp. 171-204). Syngress.
  • https://www.gim-international.com/content/blog/the-role-of-spatial-data-and-technologies-towards-building-smart-nations
  • https://documents.worldbank.org/en/publication/documents-reports/documentdetail/358501495199225866/climbing-higher-toward-a-middle-income-nepal
  • https://blogs.worldbank.org/sustainablecities/reversing-geospatial-digital-divide-one-step-or-leap-time
  • Batty, M. (2016). Big data and the city. Built Environment, 42(3), 321-337.
  • Pérez, M., Agüera, F., & Carvajal, F. (2013). Low cost surveying using an unmanned aerial vehicle. Int. Arch. Photogramm. Remote Sens. Spat. Inf. Sci, 40, 311-315.
  • Green, D. R., Hagon, J. J., Gómez, C., & Gregory, B. J. (2019). Using low-cost UAVs for environmental monitoring, mapping, and modelling: Examples from the coastal zone. In Coastal management (pp. 465-501). Academic Press.
  • Shahbazi, M., Théau, J., & Ménard, P. (2014). Recent applications of unmanned aerial imagery in natural resource management. GIScience & Remote Sensing, 51(4), 339-365.
  • Colomina, I., & Molina, P. (2014). Unmanned aerial systems for photogrammetry and remote sensing: A review. ISPRS Journal of photogrammetry and remote sensing, 92, 79-97.
  • Aber, J. S., Marzolff, I., Ries, J. B., & Aber, S. E. (2019). Unmanned Aerial Systems. Small-Format Aerial Photography and UAS Imagery, 119-139.
  • Estrada, M. A. R., & Ndoma, A. (2019). The uses of unmanned aerial vehicles–UAV’s-(or drones) in social logistic: Natural disasters response and humanitarian relief aid. Procedia Computer Science, 149, 375-383.
  • Ahmad, A., & Samad, A. M. (2010, May). Aerial mapping using high resolution digital camera and unmanned aerial vehicle for Geographical Information System. In 2010 6th International Colloquium on Signal Processing & its Applications (pp. 1-6). IEEE.
  • Everaerts, J. (2008). The use of unmanned aerial vehicles (UAVs) for remote sensing and mapping. The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 37(2008), 1187-1192.
  • Choi, K., Lee, I., Hong, J., Oh, T., & Shin, S. W. (2009, April). Developing a UAV-based rapid mapping system for emergency response. In Unmanned Systems Technology XI (Vol. 7332, pp. 75-86). SPIE.
  • Zolkepli, M. F., Ishak, M. F., Yunus, M. Y. M., Zaini, M. S. I., Wahap, M. S., Yasin, A. M., ... & Hezmi, M. A. (2021). Application of unmanned aerial vehicle (UAV) for slope mapping at Pahang Matriculation College, Malaysia. Physics and Chemistry of the Earth, Parts A/B/C, 123, 103003.
  • Colomina, I., & Molina, P. (2014). Unmanned aerial systems for photogrammetry and remote sensing: A review. ISPRS Journal of photogrammetry and remote sensing, 92, 79-97.
  • Ardi, N. D., Iryanti, M., Asmoro, C. P., Nurhayati, N., & Agustine, E. (2018, April). Mapping landslide potential area using fault fracture density analysis on unmanned aerial vehicle (UAV) image. In IOP Conference Series: Earth and Environmental Science (Vol. 145, No. 1, p. 012010). IOP Publishing.
  • Nex, F., Armenakis, C., Cramer, M., Cucci, D. A., Gerke, M., Honkavaara, E., ... & Skaloud, J. (2022). UAV in the advent of the twenties: Where we stand and what is next. ISPRS journal of photogrammetry and remote sensing, 184, 215-242.
  • Watts, A. C., Ambrosia, V. G., & Hinkley, E. A. (2012). Unmanned aircraft systems in remote sensing and scientific research: Classification and considerations of use. Remote Sensing, 4(6), 1671-1692.
  • Chabot, D. (2018). Trends in drone research and applications as the Journal of Unmanned Vehicle Systems turns five. Journal of Unmanned Vehicle Systems, 6(1), vi-xv.
  • Linchant, J., Lisein, J., Semeki, J., Lejeune, P., & Vermeulen, C. (2015). Are unmanned aircraft systems (UAS s) the future of wildlife monitoring? A review of accomplishments and challenges. Mammal Review, 45(4), 239-252.
  • Chabot, D., & Bird, D. M. (2015). Wildlife research and management methods in the 21st century: Where do unmanned aircraft fit in?. Journal of Unmanned Vehicle Systems, 3(4), 137-155.
  • Laliberte, A. S., & Rango, A. (2011). Image processing and classification procedures for analysis of sub-decimeter imagery acquired with an unmanned aircraft over arid rangelands. GIScience & Remote Sensing, 48(1), 4-23.
  • Wundram, D., & Löffler, J. (2008). High‐resolution spatial analysis of mountain landscapes using a low‐altitude remote sensing approach. International Journal of Remote Sensing, 29(4), 961-974.
  • Immerzeel, W. W., Kraaijenbrink, P. D., Shea, J. M., Shrestha, A. B., Pellicciotti, F., Bierkens, M. F., & de Jong, S. M. (2014). High-resolution monitoring of Himalayan glacier dynamics using unmanned aerial vehicles. Remote Sensing of Environment, 150, 93-103.
  • Lucieer, A., Jong, S. M. D., & Turner, D. (2014). Mapping landslide displacements using Structure from Motion (SfM) and image correlation of multi-temporal UAV photography. Progress in physical geography, 38(1), 97-116.
  • Zhang, C., & Kovacs, J. M. (2012). The application of small unmanned aerial systems for precision agriculture: a review. Precision agriculture, 13(6), 693-712.
  • Samseemoung, G., Soni, P., Jayasuriya, H. P., & Salokhe, V. M. (2012). Application of low altitude remote sensing (LARS) platform for monitoring crop growth and weed infestation in a soybean plantation. Precision Agriculture, 13(6), 611-627.
  • Herwitz, S. R., Johnson, L. F., Dunagan, S. E., Higgins, R. G., Sullivan, D. V., Zheng, J., ... & Brass, J. A. (2004). Imaging from an unmanned aerial vehicle: agricultural surveillance and decision support. Computers and electronics in agriculture, 44(1), 49-61.
  • Mancini, F., Dubbini, M., Gattelli, M., Stecchi, F., Fabbri, S., & Gabbianelli, G. (2013). Using unmanned aerial vehicles (UAV) for high-resolution reconstruction of topography: The structure from motion approach on coastal environments. Remote sensing, 5(12), 6880-6898.
  • Bemis, S. P., Micklethwaite, S., Turner, D., James, M. R., Akciz, S., Thiele, S. T., & Bangash, H. A. (2014). Ground-based and UAV-Based photogrammetry: A multi-scale, high-resolution mapping tool for structural geology and paleoseismology. Journal of Structural Geology, 69, 163-178.
  • Jensen, A. M., Morgan, D., Chen, Y., Clemens, S., & Hardy, T. (2009, January). Using multiple open-source low-cost unmanned aerial vehicles (UAV) for 3D photogrammetry and distributed wind measurement. In International Design Engineering Technical Conferences and Computers and Information in Engineering Conference (Vol. 49002, pp. 629-634).
  • Boon, M. A., Greenfield, R., & Tesfamichael, S. (2016). Unmanned aerial vehicle (UAV) photogrammetry produces accurate high-resolution orthophotos, point clouds and surface models for mapping wetlands. South African Journal of Geomatics, 5(2), 186-200.
  • Chi, Y. Y., Lee, Y. F., & Tsai, S. E. (2016, October). Study on high accuracy topographic mapping via uav-based images. In IOP Conference Series: Earth and Environmental Science (Vol. 44, No. 3, p. 032006). IOP Publishing.
  • Quaye-Ballard, N. L., Asenso-Gyambibi, D., & Quaye-Ballard, J. (2020). Unmanned Aerial Vehicle for Topographical Mapping of Inaccessible Land Areas in Ghana: A Cost-Effective Approach.
  • Azmi, S. M., Ahmad, B., & Ahmad, A. (2014, February). Accuracy assessment of topographic mapping using UAV image integrated with satellite images. In IOP Conference Series: Earth and Environmental Science (Vol. 18, No. 1, p. 012015). IOP Publishing.
  • Raid, A. T., Arthur, M., & Davis, D. (2011). Low-cost aerial mapping alternatives for natural disasters in the Caribbean. FIG Working Week.
  • Eisenbeiss, H., & Sauerbier, M. (2011). Investigation of UAV systems and flight modes for photogrammetric applications. The Photogrammetric Record, 26(136), 400-421.
  • Su, L., Huang, Y., Gibeaut, J., & Li, L. (2016). The index array approach and the dual tiled similarity algorithm for UAS hyper-spatial image processing. GeoInformatica, 20(4), 859-878.
  • Singh, K. K., & Frazier, A. E. (2018). A meta-analysis and review of unmanned aircraft system (UAS) imagery for terrestrial applications. International Journal of Remote Sensing, 39(15-16), 5078-5098.
  • https://www.opendronemap.org/webodm/
  • Nex, F., & Remondino, F. (2014). UAV for 3D mapping applications: a review. Applied geomatics, 6(1), 1-15.
  • Ahmad, M. J., Ahmad, A., & Kanniah, K. D. (2018, June). Large scale topographic mapping based on unmanned aerial vehicle and aerial photogrammetric technique. In IOP Conference Series: Earth and Environmental Science (Vol. 169, No. 1, p. 012077). IOP Publishing.
  • Udin, W. S., & Ahmad, A. (2014, February). Assessment of photogrammetric mapping accuracy based on variation flying altitude using unmanned aerial vehicle. In IOP conference series: earth and environmental science (Vol. 18, No. 1, p. 012027). IOP Publishing.
  • Gillan, J. K., Ponce‐Campos, G. E., Swetnam, T. L., Gorlier, A., Heilman, P., & McClaran, M. P. (2021). Innovations to expand drone data collection and analysis for rangeland monitoring. Ecosphere, 12(7), e03649.

Use of unmanned aerial vehicle (UAV) for mapping, and accuracy assessment of the orthophoto with and without using GCPs: A case study in Nepal

Year 2022, Volume: 4 Issue: 2, 45 - 52, 25.12.2022
https://doi.org/10.53093/mephoj.1176847

Abstract

The conventional methods of aerial photogrammetry using helicopters or airplanes are costly and challenging for small areas. For a developing country like Nepal, where Geospatial data is in high demand, a new competitive approach is essential for rapid spatial data acquisition at a low cost and time. This article demonstrates how this can be achieved using one of the evolving remote sensing technology, Unmanned Aerial Vehicles (UAVs). The application of UAVs is rapidly increasing in Nepal due to its capability of acquiring images remotely and the potential to provide data with a very high spatial and temporal resolution even in inaccessible terrain at a relatively low cost. Here, the performance of UAVs for topographical surveying and mapping has been investigated, along with the comparison between orthophoto obtained using GCPs, and without using GCPs. For this study, a DJI Phantom 3 Advanced quadcopter collected about 700 images at a flying height of 50 m above the settlement area. An orthophoto of 3.78 cm GSD covering 40.83 hectares of area was produced. With appropriate ground control points, an absolute positional accuracy of 0.035 m RMSE was achieved, whereas the output obtained without using GCPs was satisfactory. This study also highlights the use of a High-Performance Computing (HPC) system and open-source platform for rapid image processing.

References

  • Stock, K., & Guesgen, H. (2016). Geospatial reasoning with open data. In Automating open source intelligence (pp. 171-204). Syngress.
  • https://www.gim-international.com/content/blog/the-role-of-spatial-data-and-technologies-towards-building-smart-nations
  • https://documents.worldbank.org/en/publication/documents-reports/documentdetail/358501495199225866/climbing-higher-toward-a-middle-income-nepal
  • https://blogs.worldbank.org/sustainablecities/reversing-geospatial-digital-divide-one-step-or-leap-time
  • Batty, M. (2016). Big data and the city. Built Environment, 42(3), 321-337.
  • Pérez, M., Agüera, F., & Carvajal, F. (2013). Low cost surveying using an unmanned aerial vehicle. Int. Arch. Photogramm. Remote Sens. Spat. Inf. Sci, 40, 311-315.
  • Green, D. R., Hagon, J. J., Gómez, C., & Gregory, B. J. (2019). Using low-cost UAVs for environmental monitoring, mapping, and modelling: Examples from the coastal zone. In Coastal management (pp. 465-501). Academic Press.
  • Shahbazi, M., Théau, J., & Ménard, P. (2014). Recent applications of unmanned aerial imagery in natural resource management. GIScience & Remote Sensing, 51(4), 339-365.
  • Colomina, I., & Molina, P. (2014). Unmanned aerial systems for photogrammetry and remote sensing: A review. ISPRS Journal of photogrammetry and remote sensing, 92, 79-97.
  • Aber, J. S., Marzolff, I., Ries, J. B., & Aber, S. E. (2019). Unmanned Aerial Systems. Small-Format Aerial Photography and UAS Imagery, 119-139.
  • Estrada, M. A. R., & Ndoma, A. (2019). The uses of unmanned aerial vehicles–UAV’s-(or drones) in social logistic: Natural disasters response and humanitarian relief aid. Procedia Computer Science, 149, 375-383.
  • Ahmad, A., & Samad, A. M. (2010, May). Aerial mapping using high resolution digital camera and unmanned aerial vehicle for Geographical Information System. In 2010 6th International Colloquium on Signal Processing & its Applications (pp. 1-6). IEEE.
  • Everaerts, J. (2008). The use of unmanned aerial vehicles (UAVs) for remote sensing and mapping. The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 37(2008), 1187-1192.
  • Choi, K., Lee, I., Hong, J., Oh, T., & Shin, S. W. (2009, April). Developing a UAV-based rapid mapping system for emergency response. In Unmanned Systems Technology XI (Vol. 7332, pp. 75-86). SPIE.
  • Zolkepli, M. F., Ishak, M. F., Yunus, M. Y. M., Zaini, M. S. I., Wahap, M. S., Yasin, A. M., ... & Hezmi, M. A. (2021). Application of unmanned aerial vehicle (UAV) for slope mapping at Pahang Matriculation College, Malaysia. Physics and Chemistry of the Earth, Parts A/B/C, 123, 103003.
  • Colomina, I., & Molina, P. (2014). Unmanned aerial systems for photogrammetry and remote sensing: A review. ISPRS Journal of photogrammetry and remote sensing, 92, 79-97.
  • Ardi, N. D., Iryanti, M., Asmoro, C. P., Nurhayati, N., & Agustine, E. (2018, April). Mapping landslide potential area using fault fracture density analysis on unmanned aerial vehicle (UAV) image. In IOP Conference Series: Earth and Environmental Science (Vol. 145, No. 1, p. 012010). IOP Publishing.
  • Nex, F., Armenakis, C., Cramer, M., Cucci, D. A., Gerke, M., Honkavaara, E., ... & Skaloud, J. (2022). UAV in the advent of the twenties: Where we stand and what is next. ISPRS journal of photogrammetry and remote sensing, 184, 215-242.
  • Watts, A. C., Ambrosia, V. G., & Hinkley, E. A. (2012). Unmanned aircraft systems in remote sensing and scientific research: Classification and considerations of use. Remote Sensing, 4(6), 1671-1692.
  • Chabot, D. (2018). Trends in drone research and applications as the Journal of Unmanned Vehicle Systems turns five. Journal of Unmanned Vehicle Systems, 6(1), vi-xv.
  • Linchant, J., Lisein, J., Semeki, J., Lejeune, P., & Vermeulen, C. (2015). Are unmanned aircraft systems (UAS s) the future of wildlife monitoring? A review of accomplishments and challenges. Mammal Review, 45(4), 239-252.
  • Chabot, D., & Bird, D. M. (2015). Wildlife research and management methods in the 21st century: Where do unmanned aircraft fit in?. Journal of Unmanned Vehicle Systems, 3(4), 137-155.
  • Laliberte, A. S., & Rango, A. (2011). Image processing and classification procedures for analysis of sub-decimeter imagery acquired with an unmanned aircraft over arid rangelands. GIScience & Remote Sensing, 48(1), 4-23.
  • Wundram, D., & Löffler, J. (2008). High‐resolution spatial analysis of mountain landscapes using a low‐altitude remote sensing approach. International Journal of Remote Sensing, 29(4), 961-974.
  • Immerzeel, W. W., Kraaijenbrink, P. D., Shea, J. M., Shrestha, A. B., Pellicciotti, F., Bierkens, M. F., & de Jong, S. M. (2014). High-resolution monitoring of Himalayan glacier dynamics using unmanned aerial vehicles. Remote Sensing of Environment, 150, 93-103.
  • Lucieer, A., Jong, S. M. D., & Turner, D. (2014). Mapping landslide displacements using Structure from Motion (SfM) and image correlation of multi-temporal UAV photography. Progress in physical geography, 38(1), 97-116.
  • Zhang, C., & Kovacs, J. M. (2012). The application of small unmanned aerial systems for precision agriculture: a review. Precision agriculture, 13(6), 693-712.
  • Samseemoung, G., Soni, P., Jayasuriya, H. P., & Salokhe, V. M. (2012). Application of low altitude remote sensing (LARS) platform for monitoring crop growth and weed infestation in a soybean plantation. Precision Agriculture, 13(6), 611-627.
  • Herwitz, S. R., Johnson, L. F., Dunagan, S. E., Higgins, R. G., Sullivan, D. V., Zheng, J., ... & Brass, J. A. (2004). Imaging from an unmanned aerial vehicle: agricultural surveillance and decision support. Computers and electronics in agriculture, 44(1), 49-61.
  • Mancini, F., Dubbini, M., Gattelli, M., Stecchi, F., Fabbri, S., & Gabbianelli, G. (2013). Using unmanned aerial vehicles (UAV) for high-resolution reconstruction of topography: The structure from motion approach on coastal environments. Remote sensing, 5(12), 6880-6898.
  • Bemis, S. P., Micklethwaite, S., Turner, D., James, M. R., Akciz, S., Thiele, S. T., & Bangash, H. A. (2014). Ground-based and UAV-Based photogrammetry: A multi-scale, high-resolution mapping tool for structural geology and paleoseismology. Journal of Structural Geology, 69, 163-178.
  • Jensen, A. M., Morgan, D., Chen, Y., Clemens, S., & Hardy, T. (2009, January). Using multiple open-source low-cost unmanned aerial vehicles (UAV) for 3D photogrammetry and distributed wind measurement. In International Design Engineering Technical Conferences and Computers and Information in Engineering Conference (Vol. 49002, pp. 629-634).
  • Boon, M. A., Greenfield, R., & Tesfamichael, S. (2016). Unmanned aerial vehicle (UAV) photogrammetry produces accurate high-resolution orthophotos, point clouds and surface models for mapping wetlands. South African Journal of Geomatics, 5(2), 186-200.
  • Chi, Y. Y., Lee, Y. F., & Tsai, S. E. (2016, October). Study on high accuracy topographic mapping via uav-based images. In IOP Conference Series: Earth and Environmental Science (Vol. 44, No. 3, p. 032006). IOP Publishing.
  • Quaye-Ballard, N. L., Asenso-Gyambibi, D., & Quaye-Ballard, J. (2020). Unmanned Aerial Vehicle for Topographical Mapping of Inaccessible Land Areas in Ghana: A Cost-Effective Approach.
  • Azmi, S. M., Ahmad, B., & Ahmad, A. (2014, February). Accuracy assessment of topographic mapping using UAV image integrated with satellite images. In IOP Conference Series: Earth and Environmental Science (Vol. 18, No. 1, p. 012015). IOP Publishing.
  • Raid, A. T., Arthur, M., & Davis, D. (2011). Low-cost aerial mapping alternatives for natural disasters in the Caribbean. FIG Working Week.
  • Eisenbeiss, H., & Sauerbier, M. (2011). Investigation of UAV systems and flight modes for photogrammetric applications. The Photogrammetric Record, 26(136), 400-421.
  • Su, L., Huang, Y., Gibeaut, J., & Li, L. (2016). The index array approach and the dual tiled similarity algorithm for UAS hyper-spatial image processing. GeoInformatica, 20(4), 859-878.
  • Singh, K. K., & Frazier, A. E. (2018). A meta-analysis and review of unmanned aircraft system (UAS) imagery for terrestrial applications. International Journal of Remote Sensing, 39(15-16), 5078-5098.
  • https://www.opendronemap.org/webodm/
  • Nex, F., & Remondino, F. (2014). UAV for 3D mapping applications: a review. Applied geomatics, 6(1), 1-15.
  • Ahmad, M. J., Ahmad, A., & Kanniah, K. D. (2018, June). Large scale topographic mapping based on unmanned aerial vehicle and aerial photogrammetric technique. In IOP Conference Series: Earth and Environmental Science (Vol. 169, No. 1, p. 012077). IOP Publishing.
  • Udin, W. S., & Ahmad, A. (2014, February). Assessment of photogrammetric mapping accuracy based on variation flying altitude using unmanned aerial vehicle. In IOP conference series: earth and environmental science (Vol. 18, No. 1, p. 012027). IOP Publishing.
  • Gillan, J. K., Ponce‐Campos, G. E., Swetnam, T. L., Gorlier, A., Heilman, P., & McClaran, M. P. (2021). Innovations to expand drone data collection and analysis for rangeland monitoring. Ecosphere, 12(7), e03649.
There are 45 citations in total.

Details

Primary Language English
Subjects Engineering
Journal Section Research Articles
Authors

Abinash Silwal 0000-0002-2285-4643

Sunil Tamang 0000-0002-0295-9632

Rajendra Adhikari 0000-0001-6649-7097

Publication Date December 25, 2022
Published in Issue Year 2022 Volume: 4 Issue: 2

Cite

APA Silwal, A., Tamang, S., & Adhikari, R. (2022). Use of unmanned aerial vehicle (UAV) for mapping, and accuracy assessment of the orthophoto with and without using GCPs: A case study in Nepal. Mersin Photogrammetry Journal, 4(2), 45-52. https://doi.org/10.53093/mephoj.1176847
AMA Silwal A, Tamang S, Adhikari R. Use of unmanned aerial vehicle (UAV) for mapping, and accuracy assessment of the orthophoto with and without using GCPs: A case study in Nepal. MEPHOJ. December 2022;4(2):45-52. doi:10.53093/mephoj.1176847
Chicago Silwal, Abinash, Sunil Tamang, and Rajendra Adhikari. “Use of Unmanned Aerial Vehicle (UAV) for Mapping, and Accuracy Assessment of the Orthophoto With and Without Using GCPs: A Case Study in Nepal”. Mersin Photogrammetry Journal 4, no. 2 (December 2022): 45-52. https://doi.org/10.53093/mephoj.1176847.
EndNote Silwal A, Tamang S, Adhikari R (December 1, 2022) Use of unmanned aerial vehicle (UAV) for mapping, and accuracy assessment of the orthophoto with and without using GCPs: A case study in Nepal. Mersin Photogrammetry Journal 4 2 45–52.
IEEE A. Silwal, S. Tamang, and R. Adhikari, “Use of unmanned aerial vehicle (UAV) for mapping, and accuracy assessment of the orthophoto with and without using GCPs: A case study in Nepal”, MEPHOJ, vol. 4, no. 2, pp. 45–52, 2022, doi: 10.53093/mephoj.1176847.
ISNAD Silwal, Abinash et al. “Use of Unmanned Aerial Vehicle (UAV) for Mapping, and Accuracy Assessment of the Orthophoto With and Without Using GCPs: A Case Study in Nepal”. Mersin Photogrammetry Journal 4/2 (December 2022), 45-52. https://doi.org/10.53093/mephoj.1176847.
JAMA Silwal A, Tamang S, Adhikari R. Use of unmanned aerial vehicle (UAV) for mapping, and accuracy assessment of the orthophoto with and without using GCPs: A case study in Nepal. MEPHOJ. 2022;4:45–52.
MLA Silwal, Abinash et al. “Use of Unmanned Aerial Vehicle (UAV) for Mapping, and Accuracy Assessment of the Orthophoto With and Without Using GCPs: A Case Study in Nepal”. Mersin Photogrammetry Journal, vol. 4, no. 2, 2022, pp. 45-52, doi:10.53093/mephoj.1176847.
Vancouver Silwal A, Tamang S, Adhikari R. Use of unmanned aerial vehicle (UAV) for mapping, and accuracy assessment of the orthophoto with and without using GCPs: A case study in Nepal. MEPHOJ. 2022;4(2):45-52.