Imagick::thresholdImage

(PECL imagick 2.0.0)

Imagick::thresholdImage — Changes the value of individual pixels based on a threshold

bool Imagick::thresholdImage ( float $threshold [, int $channel = Imagick::CHANNEL_ALL ] )

Changes the value of individual pixels based on the intensity of each pixel compared to threshold. The result is a high-contrast, two color image.

成功时返回 TRUE。