-----Imagick  3.4.3  &&  ImageMagick 7.0.6  
-----why cannot find filter method????? 
if (!method_exists(Imagick, 'filter')) {
    echo 'undefined filter()!';
} else {
    echo 'defined filter()!';
}(PECL imagick 3 >= 3.3.0)
Imagick::filter — Applies a custom convolution kernel to the image
Imagick 3.4.4 itibariyle bu işlevin kullanımı ÖNERİLMEMEKTEDİR. Bu işleve asla güvenilmemelidir.
$ImagickKernel, int $channel = Imagick::CHANNEL_UNDEFINED): boolApplies a custom convolution kernel to the image.
ImagickKernelAn instance of ImagickKernel that represents either a single kernel or a linked series of kernels.
channel
      Normalde kanal
türü sabitlerinden biridir, ancak bitsel işleçler kullanılarak birden
fazla kanal belirtilebilir. Imagick::CHANNEL_DEFAULT
öntanımlıdır.
     
   Başarı durumunda true döner.
  
Örnek 1 Imagick::filter()
<?php
function filter($imagePath) {
    $imagick = new \Imagick(realpath($imagePath));
    $matrix = [
        [-1, 0, -1],
        [0,  5,  0],
        [-1, 0, -1],
    ];
    
    $kernel = \ImagickKernel::fromMatrix($matrix);
    $strength = 0.5;    
    $kernel->scale($strength, \Imagick::NORMALIZE_KERNEL_VALUE);    
    $kernel->addUnityKernel(1 - $strength);
    $imagick->filter($kernel);
    header("Content-Type: image/jpg");
    echo $imagick->getImageBlob();
}
?>-----Imagick  3.4.3  &&  ImageMagick 7.0.6  
-----why cannot find filter method????? 
if (!method_exists(Imagick, 'filter')) {
    echo 'undefined filter()!';
} else {
    echo 'defined filter()!';
}-----Imagick::filter cannot work!
-----suse linux server   ,   imagick module version 3.4.3
-----run Example #1 Imagick::filter()  , there is no result!  where is problem?
thank you for your answer!
Alex