The second parameter will update the result of getFilename() if set. Otherwise the result of getFilename() will retain its original value, prior to calling readImageFile().
(PECL imagick 2.0.0)
Imagick::readImageFile — Reads image from open filehandle
$filehandle
[, string $fileName = NULL
] ) : boolReads image from open filehandle
filehandle
fileName
成功时返回 TRUE。
错误时抛出 ImagickException。
The second parameter will update the result of getFilename() if set. Otherwise the result of getFilename() will retain its original value, prior to calling readImageFile().
An example of reading an image file from a URL, using a handle returned by fopen():
<?php
$handle = fopen('http://example.com/foo.jpg', 'rb');
$img = new Imagick();
$img->readImageFile($handle);
$img->resizeImage(128, 128, 0, 0);
$img->writeImage('images/foo.jpg');
?>