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Author Topic: Relationship PIXEL SIZE and AREA  (Read 2350 times)

Vinicius

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Relationship PIXEL SIZE and AREA
« on: October 31, 2015, 11:38:41 PM »
Hello,

I would like to know what is the relationship between the pixel size and calculated area (and volume too).
I think the agisoft use the information of the pixel size to calculate area and volume. But how the software know this information? Can I provide this information to the software?

Im trying to calculate area and volume of a maize crop...

Sorry to grammatical errors.

Thanks!

Wishgranter

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Re: Relationship PIXEL SIZE and AREA
« Reply #1 on: November 01, 2015, 06:22:56 PM »
search for GSD calculation ´GroundSamplingDistance, how it is calculated and etc.. 
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Arie

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Re: Relationship PIXEL SIZE and AREA
« Reply #2 on: November 02, 2015, 02:18:44 PM »
Hi,
if you are trying to calculate the area and volume of a maize crop, you will need ground control points (GCPs) or at least a scale-bar in the images. The initial pointcloud from Photoscan is arbitrary i.e. it does not have a scale or position in space, therefore you cannot calculate the area/ volume without reference.
Cheers.