Here's a example of this function:
<?php
$img = new Imagick();
$img->readImage($image_file_name);
$img->blackThresholdImage('grey');
$img->writeImage($thumb_file_name);
$img->clear();
$img->destroy();
?>
Imagick::blackThresholdImage
(PECL imagick 2.0.0)
Imagick::blackThresholdImage — Forces all pixels below the threshold into black
Description
Warning
This function is currently not documented; only its argument list is available.
Is like Imagick::thresholdImage() but forces all pixels below the threshold into black while leaving all pixels above the threshold unchanged.
Parameters
- threshold
-
The threshold below which everything turns black
Return Values
Returns TRUE on success.
Changelog
| Version | Description |
|---|---|
| 2.1.0 | Now allows a string representing the color as a parameter. Previous versions allow only an ImagickPixel object. |
Imagick::blackThresholdImage
elmer at web-axis dot net
30-Nov-2008 09:33
30-Nov-2008 09:33
