Within the science project we are watering grass with water using different level and technique of treatment and cleaning. We measure traces of biological and chemical materials within the soil as well as within the plants. And we have also series of pictures of the grass.
I'm looking for some ideas how to come up with measure how to convert the image into some sort of greenness index, preferably as a single number or short vector of few numbers. The plan is to correlate it later to point in time and to level of chemical elements in the plants.
Here are some images - two different water treatments, monthly images from June to October:
| Sample | June | July | August | September | October |
|---|---|---|---|---|---|
| Sample 1 |  |
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| Sample 2 |  |
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Any idea or suggestion is welcome...