ASSESSMENT OF PLANT LEAF AREA MEASUREMENT BY USING STEREO- VISION

The aim of this study is to develop an alternative
measurement for the leaf area index (LAI), an important
agronomic parameter for plant growth assessment. A 3D
stereo-vision technique was developed to measure both leaf
area and corresponding ground area. The leaf area was
based on pixel related measurements while the ground area
was based on the mean distance from the leaves to the
camera. Laboratory and field experiments were undertaken
to estimate the accuracy and the precision of the technique.
Result showed that, though the leaves-camera distance had
to be estimated precisely in order to have accurate
measurement, the precision of the LAI evaluation, after
regression, was equivalent to the reference measurements,
that is to say around 10% of the estimated value. This
shows the potential of the 3D measurements compared with
tedious reference measurements.