image is printed to stdout. Default is <b class=
"const">false</b>.</p>
</dd>

<dt><b class="option">-nchan</b> <i class="arg">int</i></dt>

<dd>
<p>Specify the number of channels of the generated image. Default
is <b class="const">1</b>, i.e. generate a grayscale image.</p>
</dd>

<dt><b class="option">-gamma</b> <i class="arg">float</i></dt>

<dd>
<p>Specify a gamma correction to be applied when mapping the input
data to 8-bit image values. Default is <b class=
"const">1.0</b>.</p>
</dd>

<dt><b class="op