You need to pass this function a colour:
<?php
$img->blackThresholdImage( "#FFFFFF" );
?>
E.g. this blackens any pixel which isn't pure white.
(PECL imagick 2.0.0)
Imagick::blackThresholdImage — Forces all pixels below the threshold into black
Is like Imagick::thresholdImage() but forces all pixels below the threshold into black while leaving all pixels above the threshold unchanged.
threshold
The threshold below which everything turns black
Returns TRUE
on success.
Version | Beskrivelser |
---|---|
2.1.0 | Now allows a string representing the color as a parameter. Previous versions allow only an ImagickPixel object. |
You need to pass this function a colour:
<?php
$img->blackThresholdImage( "#FFFFFF" );
?>
E.g. this blackens any pixel which isn't pure white.
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();
?>