Index: wp-includes/class-wp-image-editor-gd.php
===================================================================
--- wp-includes/class-wp-image-editor-gd.php	(revision 26234)
+++ wp-includes/class-wp-image-editor-gd.php	(working copy)
@@ -87,6 +87,7 @@
 			return new WP_Error( 'error_loading_image', __('File doesn’t exist?'), $this->file );
 
 		// Set artificially high because GD uses uncompressed images in memory
+		/** This filter is documented in wp-includes/class-wp-image-editor-imagick.php */
 		@ini_set( 'memory_limit', apply_filters( 'image_memory_limit', WP_MAX_MEMORY_LIMIT ) );
 		$this->image = @imagecreatefromstring( file_get_contents( $this->file ) );
 
@@ -361,6 +362,7 @@
 				return new WP_Error( 'image_save_error', __('Image Editor Save Failed') );
 		}
 		elseif ( 'image/jpeg' == $mime_type ) {
+			/** This filter is documented in wp-includes/class-wp-image-editor-imagick.php */
 			if ( ! $this->make_image( $filename, 'imagejpeg', array( $image, $filename, apply_filters( 'jpeg_quality', $this->quality, 'image_resize' ) ) ) )
 				return new WP_Error( 'image_save_error', __('Image Editor Save Failed') );
 		}
@@ -375,6 +377,7 @@
 
 		return array(
 			'path' => $filename,
+			/** This filter is documented in wp-includes/class-wp-image-editor-imagick.php */
 			'file' => wp_basename( apply_filters( 'image_make_intermediate_size', $filename ) ),
 			'width' => $this->size['width'],
 			'height' => $this->size['height'],
Index: wp-includes/class-wp-image-editor-imagick.php
===================================================================
--- wp-includes/class-wp-image-editor-imagick.php	(revision 26234)
+++ wp-includes/class-wp-image-editor-imagick.php	(working copy)
@@ -119,6 +119,13 @@
 		if ( ! is_file( $this->file ) && ! preg_match( '|^https?://|', $this->file ) )
 			return new WP_Error( 'error_loading_image', __('File doesn’t exist?'), $this->file );
 
+		/**
+		 * Filter the memory limit allocated to either GD or Imagick for image manipulation.
+		 *
+		 * @since 3.2.0
+		 *
+		 * @param string Maximum memory limit to allocate (default is 256M).
+		 */
 		// Even though Imagick uses less PHP memory than GD, set higher limit for users that have low PHP.ini limits
 		@ini_set( 'memory_limit', apply_filters( 'image_memory_limit', WP_MAX_MEMORY_LIMIT ) );
 
@@ -160,6 +167,14 @@
 
 		try {
 			if( 'image/jpeg' == $this->mime_type ) {
+				/**
+				 * Filter the quality of the JPEG before it's saved.
+				 *
+				 * @since 2.5.0
+				 *
+				 * @param int 		$quality 	Quality level between 0 (low) and 100 (high) of the JPEG.
+				 * @param string 				The context of the filter.
+				 */
 				$this->image->setImageCompressionQuality( apply_filters( 'jpeg_quality', $quality, 'image_resize' ) );
 				$this->image->setImageCompression( imagick::COMPRESSION_JPEG );
 			}
@@ -449,6 +464,13 @@
 
 		return array(
 			'path' => $filename,
+			/**
+			 * Filter the name of the saved image file.
+			 *
+			 * @since 2.6.0
+			 *
+			 * @param string $filename Name of the file.
+			 */
 			'file' => wp_basename( apply_filters( 'image_make_intermediate_size', $filename ) ),
 			'width' => $this->size['width'],
 			'height' => $this->size['height'],