PROGRAMMES | LUMEN
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During Enrichment Day , the app turned out well in certain areas . I managed to make sure that the light sensor value was only from an actual light sensor and not some wizardry from the camera . However , there were inconsistencies in the calculation for canopy cover .
Overall , I learned much about the potential and limitations of Mobile APIs from this experience . I hope I can improve the app in the future .
The goal of Geoscan was to allow the user to easily check the light intensity and the percentage of canopy cover in a photograph of a location in the rainforest and enables the user to store the results to Google Drive for easy retrieval later . Measuring light intensity was easy as most phones have a light sensor in them ( which is usually there to control screen brightness ). I had initially wanted to make the app compatible to both iOS and Android phones , but I had to drop any possible support for iOS as I could not figure out if there was any API provided by Apple for the iPhone ’ s light sensor .
Canopy cover was a totally different problem , I had absolutely no way to accurately calculate it though I had gone for multiple field testing . My code , as of now , simply iterates through every pixel in the photograph taken of the canopy cover and takes the average of the RGB value , grey-scaling it , and checks if it is below or above a certain threshold . The accuracy also depends on how the photo is taken , such as whether the photograph includes other forest layers and not just the canopy layer .
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This activity exposes students to real-life data collection and analysis using Geographical and Mathematical lenses , which is an important aspect of the Inquiry approach in Level 2 Learning .
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Facing pagev : Students taking lux reading of the amount of sunlight on the forest floor using the GeoScan app .
This page ( top left ): For accuracy of data collection , this student is ensuring that the lux reading is taken below the canopy and not along the footpath .
This page ( bottom ): Students measure the percentage of canopy coverage using the GeoScan app .
This page ( top right ): The app interface developed for Enrichment Day .