Technique used is showcased in my blog, which goes over the theory behind this project and the coding used to created NDVI images from single images.
Using customized filters with an IR-converted Hasselblad camera onboard my DJI Mavic 2 Pro Drone I have been able to create a versatile imaging system that can see in the Near-Infrared for use in NDVI vegetation monitoring, indexing and classification.
The NIR images and videos created are vibrant and interesting in and of themselves too and can open a door to new ways to create eye-catching and novel imagery to give a more in-depth appreciation of the complexity of the environment.
Commerially available multispectral cameras, though useful tools, are often expensive. With the right filters to assign an NIR Channel over the Red band and proper leveraging using Blue and/or Green bands we can creat a type of approximation to NDVI and ENDVI Classification using only single cameras and single deployment. That is the focus of this research. The artistic value is a spin-off of sorts but equally interesting in my opinion.
The test shown here is of a reservoir in Ireland called Blessington Lake, officially Pollaphuca. It is a bird conservation site and source of water for local use. This reservoir was created artificially by the construction of Pollaphuca Dam for use in Hydroelectricity production.
I find this is a very good site to test general environmental boundaries, such as that between a forested area, a shoreline and the water itself.
This test also shows that shadows are diminished if the drone imaging is performed during overcast weather, however the overall NIR reflectance information is very clear. This is an important detail as NDVI generating satellites cannot penetrate cloud covered areas, so Drones add an advantage in this regard.
Moreover, the resolution on the ground using a drone at a height of 100m can be as low as 2cm per pixel, a resolution not possible using satellites and this information is needed for close environmental monitoring and species classification, particularly in wild areas.