I am using a script called "test.php" in the root of WordPress with a folder for images called "test-images/*". The original image is called "scott.jpg" - change that value with your image to play along

wp-imagick-access.php

<?php
error_reporting(-1);

require( 'wp-load.php' );
require_once( ABSPATH . WPINC . '/class-wp-image-editor.php' );
require_once( ABSPATH . WPINC . '/class-wp-image-editor-imagick.php' );

/**
 * Tosses Imagick methods up the chain to WP_Image_Editor_Imagick::image.
 *  WP_Image_Editor_Imagick::image is protected, so you can't act on
 *	it directly in an instance / there is no getter. Decorator pattern was an 
 *	odd choice here IMO. Probably because its functionality is purposely limited
 *  to the immediate needs of core. Eh.
 * 
 * Activates the Builder pattern on Imagick methods.
 * 
 * Output the edited image:     
 *		get_cropped()->adaptiveBlurImage(5, 3)->stream();
 * Save the edited image: 
 *		get_cropped()->adaptiveBlurImage(5, 3)->write( 'blur', false ); 
 * Save the edited image and then display it in an <img> tag: 
 *		get_cropped()->adaptiveBlurImage(5, 3)->write( 'blur' ); 
 */
class WP_Imagick_Access extends WP_Image_Editor_Imagick {
	function __call( $name, $arguments ) {
		call_user_func_array( array( $this->image, $name ), $arguments );
		return $this;
	}
	
	static function __callStatic( $name, $arguments ) {
		call_user_func_array( array( $this->image, $name ), $arguments );
		return $this;
	}	
	/**
	 * This works better when using Imagick method to overload
	 * 
	 * @param string $mime_type
	 */
	function stream( $mime_type = 'image/jpeg' ) {
		header( "Content-Type: $mime_type" );
		echo $this->image;
	}
	
	/**
	 * Save an image and output an <img> tag
	 * 
	 * @param string $name
	 * @param boolean $display
	 * @return \WP_Imagick_Access
	 */
	function write( $name, $display = true ) {
		//if ( ! file_exists( "test-images/$name.jpg" ) )
			$this->save( "test-images/$name.jpg" );
		
		if ( $display )
			echo '<img src="', home_url( "test-images/$name.jpg" ), '" />';	
		
		return $this;
	}
}

function add_wp_imagick_access( $editors ) {
	array_unshift( $editors, 'WP_Imagick_Access' );
	return $editors;
}

add_filter( 'wp_image_editors', 'add_wp_imagick_access' );

/**
 * Change size to create new image
 * 
 * @return WP_Image_Editor_Imagick
 */
function get_cropped() {
	$size = 250;
	
	if ( ! file_exists( 'test-images/cropped-' . $size . '.jpg' ) ) {
		$image = wp_get_image_editor( 'scott.jpg' );
		$image->resize( $size, $size, true );
		$image->write( 'test-images/cropped-' . $size . '.jpg', false );		
	}
	
	return wp_get_image_editor( 'test-images/cropped-' . $size . '.jpg' );
}

/**
 * Imagick CHANNEL constants
 */
$channel = array();
foreach ( array( 'DEFAULT', 'RED', 'GRAY', 'CYAN', 'GREEN', 'MAGENTA', 'BLUE', 'YELLOW', 'ALPHA', 'OPACITY', 'MATTE', 'BLACK', 'INDEX', 'ALL', 'UNDEFINED' ) as $chan ) {
	$channel["imagick::CHANNEL_{$chan}"] = constant( "imagick::CHANNEL_{$chan}" );
}
/**
 * Imagick NOISE constants
 */
$noise = array();
foreach ( array( 'UNIFORM', 'GAUSSIAN', 'MULTIPLICATIVEGAUSSIAN', 'IMPULSE', 'LAPLACIAN', 'POISSON', 'RANDOM' ) as $nois ) {
	$noise["imagick::NOISE_{$nois}"] = constant( "imagick::NOISE_{$nois}" );
}	

/**
 * Min / Max floats for generic parameters - still tweaking ideal values for these
 */
$radius = array( 0.5, 50 );
$sigma = array( 0.5, 20 );
$angle = array( 0.0, 360.0 );
$opacity = array( 0.0, 1.0 );
$percentage = array( 0.0, 100.0 );

/**
 * Since we operate by convention:
 * slug => array( method, array( param1 => array( min, max ), ... ) ) 
 * 
 * TODO: some of the 0.0 values are wrong, still learning what each method does
 * 
 */
$map = array(
	'adaptive-blur' => array( 'adaptiveBlurImage', array( 'radius' => $radius,  'sigma' => $sigma, 'channel' => $channel ) ),
	'adaptive-threshold' => array( 'adaptiveThresholdImage', array( 'width' => 0.0, 'height' => 0.0, 'offset' => 0.0 ) ),
	'adaptive-sharpen' => array( 'adaptiveSharpenImage', array( 'radius' => $radius,  'sigma' => $sigma, 'channel' => $channel ) ),
	'noise' => array( 'addNoiseImage', array( 'noise_type' => $noise, 'channel' => $channel ) ),
	'blur' => array( 'blurImage', array( 'radius' => $radius,  'sigma' => $sigma, 'channel' => $channel ) ),
	'charcoal' => array( 'charcoalImage', array( 'radius' => $radius,  'sigma' => $sigma ) ), 
	'edge' => array( 'edgeImage', array( 'radius' => $radius ) ),
	'emboss' => array( 'embossImage', array( 'radius' => $radius,  'sigma' => $sigma ) ), 
	'median' => array( 'medianFilterImage', array( 'radius' => $radius ) ), 
	'modulate' => array( 'modulateImage', array( 'brightness' => $percentage , 'saturation' => $percentage, 'hue' => $percentage ) ),
	'motion' => array( 'motionBlurImage', array( 'radius' => $radius,  'sigma' => $sigma, 'angle' => $angle, 'channel' => $channel ) ),
	'normalize' => array( 'normalizeImage', array( 'channel' => $channel ) ),
	'oilpaint' => array( 'oilPaintImage', array( 'radius' => $radius ) ),
	'radial-blur' => array( 'radialBlurImage', array( 'angle' => $angle, 'channel' => $channel ) ),
	'random-threshold' => array( 'randomThresholdImage', array( 'low' => 0.0, 'high' => 0.0, 'channel' => $channel ) ),
	'reduce-noise' => array( 'reduceNoiseImage', array( 'radius' => $radius ) ),
	'resample' => array( 'resampleImage', array( 'x_resolution' => 0.0, 'y_resolution' => 0.0, 'filter' => 0.0 , 'blur' => 0.0 ) ),	
	'sepia' => array( 'sepiaToneImage', array( 'threshold' => $percentage ) ),
	'shade' => array( 'shadeImage', array( 'gray' => $percentage, 'azimuth' => $percentage, 'elevation' => $percentage ) ),
	'sharpen' => array( 'sharpenImage', array( 'opacity' => $opacity, 'sigma' => $sigma, 'x' => 0.0, 'y' => 0.0 ) ),
	'sketch' => array( 'sketchImage', array( 'radius' => $radius,  'sigma' => $sigma, 'angle' => $angle ) ),
	'solarize' => array( 'solarizeImage', array( 'threshold' => 0.0 ) ),
	'spread' => array( 'spreadImage', array( 'radius' => $radius ) ),
	'swirl' => array( 'swirlImage', array( 'degrees' => $angle ) ),
	'tint' => array( 'tintImage', array( 'tint' => $percentage, 'opacity' => $opacity ) ),
	'unsharp' => array( 'unsharpMaskImage', array( 'radius' => $radius,  'sigma' => $sigma, 'amount' => 0.0, 'threshold' => 0.0, 'channel' => $channel ) ), 
	'vignette' => array( 'vignetteImage', array( 'black' => $percentage, 'white' => $percentage, 'x' => 0.0, 'y' => 0.0 ) ),
	'wave' => array( 'waveImage', array( 'amplitude' => $percentage, 'length' => 0.0 ) ),
);

/**
 * Handle a request to resample the cropped image
 * 
 */
if ( isset( $_GET['slug'] ) ) {

	list( $method, $params ) = $map[$_GET['slug']];
	
	$args = array();
	foreach ( $params as $arg => $default ) {
		if ( isset( $_GET[$arg] ) ) {
			$passed = $_GET[$arg];

			if ( is_array( $default ) && empty( $passed ) )
				$passed = reset( $default );

			if ( is_int( $passed ) || in_array( $arg, array( 'channel', 'noise_type' ) ) )
				$cast = intval( $passed );
			else	
				$cast = floatval( $passed );

			$args[$arg] = $cast;			
		} else {
			if ( is_array( $default ) )
				$args[$arg] = reset( $default );
			else 
				$args[$arg] = $default;
		}
	}
	
	$obj = get_cropped();
	/**
	 * Depending on how cray you get, you might run into a memory alloc fatal
	 *   if out of sync params are passed (working on it!)
	 */
	try {
		call_user_func_array( array( $obj, $method ), $args );
	} catch (Exception $e) {
		$obj = get_cropped();
	}
	
	$obj->stream();
	exit();
}
/** end resampling */

/**
 * UI for ImageMagick methods 
 * 
 */

wp_register_style( 'jquery-ui', '/test-images/jquery-ui-1.9.2.custom.min.css' );

wp_print_styles( array( 'jquery-ui' ) );
wp_print_scripts( array( 'jquery-ui-slider' ) );

/**
 * Inline Styles
 * 
 */
?>
<style>	
* {margin: 0; padding: 0}
body {font-family: helvetica; padding: 20px; font-size: 12px}
h3 {margin: 10px 0; font-family: monospace; font-weight: normal}
#images {overflow: hidden}	
.image {float: left; margin: 0 10px 10px 0; width: 250px; height: 470px; margin-bottom: 20px}
.image-frame {display: block; width: 250px; height: 250px; overflow: hidden; background: #eee}
img {display: block}
.slider, select {display: block; margin: 10px; width: 85%}
.reset-me {color: red; cursor: pointer; text-decoration: underline}

.ui-slider .ui-slider-handle {widht: 0.9em; height: 0.9em}
.ui-slider-horizontal {height: 0.6em}
</style>
<script type="text/javascript">
/**
 * UI event handlers
 * 
 */	
(function ($) {
	var locked = false;
	
	window.resample = function (event) {
		if (locked)
			return;
		
		var elem = $(event.target), wrap, query, sliders = $('.slider');
		
		sliders.slider({disabled: true});
		
		wrap = elem.closest('.image');
		
		query = {slug: wrap.prop('id')};
		
		wrap.find('.slider').map(function (index, slider) {
			slider = $(slider);
			
			slider.prev('label').find('span').text(slider.slider('value'));
			query[slider.data('name')] = slider.slider('value');
		});
		
		wrap.find('select').map(function (index, widg) {
			widg = $(widg);
			query[widg.prop('name')] = widg.val();
		});
		
		/**
		 * Sigma can't be greater than radius, also blows up when 0
		 */
		if (query.sigma && query.radius && query.sigma > query.radius) {
			query.sigma = query.radius;
			wrap.find('.slider[data-name="sigma"]').slider('value', query.radius);
		}
		
		/**
		 * Replace the image with the URL for the altered one
		 */
		wrap.find('img').replaceWith($('<img/>').attr({src: '/test.php?' + $.param(query)}));
		
		sliders.slider({disabled: false});
	};
	
	/**
	 * Reload cropped image and reset sliders
	 */
	window.reset_me = function (e) {
		locked = true;
		
		var wrap = $(e.target).closest('.image');
		wrap.find('.slider').slider('value', 0);
		wrap.find('select').val('');
		wrap.find('img').replaceWith($('<img/>').attr({src: '/test-images/cropped-250.jpg'}));
		
		locked = false;
	};
	
}(jQuery));
</script>

<div id="images">
	
	<?php 
	foreach ( $map as $slug => $data ): 
		list( $method, $params ) = $data;
	?>
	
	<div class="image" id="<?php echo $slug ?>">
		<div class="image-frame">
			<img src="http://wordpress-core/test-images/cropped-250.jpg"/>
		</div>
		
		<h3>Imagick::<?php echo $method ?></h3>
		
		<?php 
		/**
		 * Values are not dynamic
		 */
		foreach ( $params as $key => $default ): 
			if ( in_array( $key, array( 'channel', 'noise_type' ) ) ): ?>
			<label><?php echo ucwords( str_replace( '_', ' ', $key ) ) ?></label> 
			<select name="<?php echo $key ?>">
<?php 
				foreach ( $default as $const => $value ): ?>
				<option value="<?php echo $value ?>"><?php echo $const ?></option>
<?php 
				endforeach; 
?>
			</select>
<?php 
			/**
			 * Output minimum for jQuery UI slider
			 */
			else: 
?>
			<label><?php echo ucwords( $key ) ?> <span></span></label>
			<div class="slider <?php echo $key ?>" data-name="<?php echo $key ?>"></div>	
		<?php
			endif;
		endforeach ?>
		<a class="reset-me">Reset</a>	
		<script type="text/javascript">
		jQuery(function ($) {	
<?php 
	/**
	 * For now, output JS inline for each item
	 * Convert max / min to padded int - will be coverted to float later
	 * 
	 */

	foreach ( $params as $key => $default ): 
		if ( in_array( $key, array( 'channel', 'noise_type' ) ) )
			continue;

		if ( is_array( $default ) ): 
			$start = reset( $default );
			$end = end( $default );
		?>
		var elem = $('#<?php echo $slug, ' .', $key ?>'), params = {
			animate: true,
			min: <?php echo $start ?>, 
			max: <?php echo $end ?>,
			stop : resample,
			step : 1
		};	

		elem.slider(params);
<?php 
	else: 
		/**
		 * These are the 0.0 values, these may sorta work for some params
		 *   but need appropriate default ranges later
		 */
?>
		var elem = $('#<?php echo $slug, ' .', $key ?>'), params = {
			animate: true,
			min : <?php echo $default ?>, 
			max : 800, 
			stop : resample, 
			step : 1
		};			
		
		elem.slider(params);
<?php 
		endif;
	endforeach ?>	
		});
		</script>		
	</div>

	<?php endforeach ?>
</div>
<script type="text/javascript">
/**
 * Generical handlers
 */	
jQuery(function ($) {
	$('select').change(resample);
	$('.reset-me').click(reset_me);
});
</script>