Imagick::adaptiveThresholdImage()
(PECL imagick 2.0.0)
Selects a threshold for each pixel based on a range of intensity
说明
Imagick::adaptiveThresholdImage(int $width,int $height,int $offset): bool
Selects an individual threshold for each pixel based on the range of intensity values in its local neighborhood. This allows for thresholding of an image whose global intensity histogram doesn't contain distinctive peaks.
参数
- $width
Width of the local neighborhood.
- $height
Height of the local neighborhood.
- $offset
The mean offset
返回值
成功时返回TRUE
。
范例
Example #1 Imagick::adaptiveThresholdImage()
<?php function adaptiveThresholdImage($imagePath, $width, $height, $adaptiveOffset) { $imagick = new \Imagick(realpath($imagePath)); $adaptiveOffsetQuantum = intval($adaptiveOffset * \Imagick::getQuantum()); $imagick->adaptiveThresholdImage($width, $height, $adaptiveOffsetQuantum); header("Content-Type: image/jpg"); echo $imagick->getImageBlob(); } ?>