Warning: This function is
currently not documented; only the argument list is
available.
Warning: This function is
EXPERIMENTAL. The behaviour of this function, the
name of this function, and anything else documented about this
function may change without notice in a future release of PHP.
Use this function at your own risk.
Writes an image to the specified filename. If the filename parameter is NULL,
the image is written to the filename set by Imagick::ReadImage() or
Imagick::SetImageFilename().
Return Values
Returns TRUE
on success.