zenith_image

Build a single-layer image with zenith angle values, assuming upwards-looking
hemispherical photography with the optical axis vertically aligned.

Tools for preprocessing and processing canopy photographs with
support for raw data reading. Provides methods to address variability in
sky brightness and to mitigate errors from image acquisition in
non-diffuse light. Works with all types of fish-eye lenses, and some
methods also apply to conventional lenses.

Gast<c3><b3>n Mauro D<c3><ad>az

rcaiman

CAnopy IMage ANalysis

Gastón Mauro Díaz

zenith_image function

<dl><dt>diameter</dt>
<dd>numeric vector of length one. Diameter in pixels expressed as
an even integer. This places the zenith point between pixels. Snapping the
zenith point between pixels does not affect accuracy because half-pixel
is less than the uncertainty in localizing the circle within the
picture.</dd>
<dt>lens_coef</dt>
<dd>numeric vector. Polynomial coefficients of the lens
projection function. See <code>lens()</code>.</dd></dl>

Arguments

Build Zenith image — zenith_image

<dl>

<dt>diameter</dt>
<dd>numeric vector of length one. Diameter in pixels expressed as
an even integer. This places the zenith point between pixels. Snapping the
zenith point between pixels does not affect accuracy because half-pixel
is less than the uncertainty in localizing the circle within the
picture.</dd>


<dt>lens_coef</dt>
<dd>numeric vector. Polynomial coefficients of the lens
projection function. See <code>lens()</code>.</dd>

</dl>

zenith_image: Build Zenith image

Description

Usage

Value

Arguments

Examples