How to override the Drupal plugin's function? - drupal

Question

I am new in Drupal.
I am using imagemagick plugin for modify images. My problem is when it resize GIF image the image got messed up. I search the solution on internet i found the changes regarding that.
but i don't want to write code changes directly to plugins module file.
I want to override it's image_imagemagick_resize() function. I can not figure out how to Override it and where to put it's override function.
Default Function :-
function image_imagemagick_resize(stdClass $image, $width, $height) {
$image->ops[] = '-resize ' . (int) $width . 'x' . (int) $height . '!';
$image->info['width'] = $width;
$image->info['height'] = $height;
return TRUE;
}
Override Function:
function imageapi_imagemagick_image_resize(&$image, $width, $height) {
$extra = '';
if($image->info['mime_type'] == 'image/gif') {
$extra = '-coalesce ';
}
$image->ops[] = $extra . '-resize '. (int) $width .'x'. (int) $height .'!';
$image->info['width'] = $width;
$image->info['height'] = $height;
return TRUE;
}
Thanks

Answer 1

Hopefully image_imagemagick_resize invokes alter hooks via _image_imagemagick_alter_invoke :
function image_imagemagick_resize($source, $dest, $width, $height) {
$args = array('resize' => '-resize ' . (int) $width . 'x' . (int) $height . '!');
$args = _image_imagemagick_alter_invoke('resize', $source, $args);
return _image_imagemagick_convert($source, $dest, $args);
}
function _image_imagemagick_alter_invoke($op, $filepath, $args) {
foreach (module_implements('imagemagick_alter') as $module) {
$function = $module . '_imagemagick_alter';
$function($op, $filepath, $args);
}
return $args;
}
So you can override the resize parameters by implementing the hook_imagemagick_alter() in a custom module :
function mymodule_imagemagick_alter($op, $filepath, &$args) {
# altering $args...
}