(No version information available, might be only in CVS)
Imagick::blackThresholdImage — Forces all pixels below the threshold into black
This function is currently not documented; only the argument list is available.
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.
Is like Imagick::thresholdImage() but forces all pixels below the threshold into black while leaving all pixels above the threshold unchanged.
The threshold below which everything turns black
Returns TRUE on success.