Changeset 36891

Timestamp:

03/09/2016 04:43:40 AM (9 years ago)

Author:

mikeschroder

Message:

Media: Progressive enhancement for Imagick; add profiles to whitelist.

• Progressive enhancement for optional compression improvements and stripping meta.
• Whitelist IPTC and XMP profiles to maintain Copyright and Rights Usage Terms.
• Whitelist EXIF profile to maintain orientation information. If handled on upload in the future, it can be stripped as well.

Fixes #33642. See #28634.
Props joemcgill, juliobox, ahockley, markoheijnen, adamsilverstein, wonderboymusic, mikeschroder.

File:

• trunk/src/wp-includes/class-wp-image-editor-imagick.php (modified) (8 diffs)

trunk/src/wp-includes/class-wp-image-editor-imagick.php

@@ -63 +63 @@
             'getimageblob',
             'getimagegeometry',
-            'getimagedepth',
             'getimageformat',
             'setimageformat',
             'setimagecompression',
             'setimagecompressionquality',
-            'setimagedepth',
             'setimagepage',
-            'setimageproperty',
-            'setinterlacescheme',
+            'setoption',
             'scaleimage',
             'cropimage',
@@ -77 +74 @@
             'flipimage',
             'flopimage',
-            'unsharpmaskimage',
         );
 
         // Now, test for deep requirements within Imagick.
-        if ( ! ( defined( 'imagick::COMPRESSION_JPEG' ) && defined( 'imagick::FILTER_TRIANGLE' ) ) )
+        if ( ! defined( 'imagick::COMPRESSION_JPEG' ) )
             return false;
 
@@ -305 +301 @@
             $filter = constant( 'Imagick::' . $filter_name );
         } else {
-            $filter = Imagick::FILTER_TRIANGLE;
+            $filter = defined( 'Imagick::FILTER_TRIANGLE' ) ? Imagick::FILTER_TRIANGLE : false;
         }
 
@@ -318 +314 @@
          * @param bool $strip_meta Whether to strip image metadata during resizing. Default true.
          */
-        $strip_meta = apply_filters( 'image_strip_meta', $strip_meta );
-
-        // Strip image meta.
-        if ( $strip_meta ) {
-            $strip_result = $this->strip_meta();
-
-            if ( is_wp_error( $strip_result ) ) {
-                return $strip_result;
-            }
+        if ( apply_filters( 'image_strip_meta', $strip_meta ) ) {
+            $this->strip_meta(); // Fail silently if not supported.
         }
 
@@ -335 +324 @@
              * unless we would be resampling to a scale smaller than 128x128.
              */
-            $resize_ratio = ( $dst_w / $this->size['width'] ) * ( $dst_h / $this->size['height'] );
-            $sample_factor = 5;
-
-            if ( $resize_ratio < .111 && ( $dst_w * $sample_factor > 128 && $dst_h * $sample_factor > 128 ) ) {
-                $this->image->sampleImage( $dst_w * $sample_factor, $dst_h * $sample_factor );
-            }
-
-            // Resize to the final output size.
-            $this->image->setOption( 'filter:support', '2.0' );
-            $this->image->resizeImage( $dst_w, $dst_h, $filter, 1 );
+            if ( is_callable( array( $this->image, 'sampleImage' ) ) ) {
+                $resize_ratio = ( $dst_w / $this->size['width'] ) * ( $dst_h / $this->size['height'] );
+                $sample_factor = 5;
+
+                if ( $resize_ratio < .111 && ( $dst_w * $sample_factor > 128 && $dst_h * $sample_factor > 128 ) ) {
+                    $this->image->sampleImage( $dst_w * $sample_factor, $dst_h * $sample_factor );
+                }
+            }
+
+            /*
+             * Use resizeImage() when it's available and a valid filter value is set.
+             * Otherwise, fall back to the scaleImage() method for resizing, which
+             * results in better image quality over resizeImage() with default filter
+             * settings and retains backwards compatibility with pre 4.5 functionality.
+             */
+            if ( is_callable( array( $this->image, 'resizeImage' ) ) && $filter ) {
+                $this->image->setOption( 'filter:support', '2.0' );
+                $this->image->resizeImage( $dst_w, $dst_h, $filter, 1 );
+            } else {
+                $this->image->scaleImage( $dst_w, $dst_h );
+            }
 
             // Set appropriate quality settings after resizing.
             if ( 'image/jpeg' == $this->mime_type ) {
-                $this->image->unsharpMaskImage( 0.25, 0.25, 8, 0.065 );
+                if ( is_callable( array( $this->image, 'unsharpMaskImage' ) ) ) {
+                    $this->image->unsharpMaskImage( 0.25, 0.25, 8, 0.065 );
+                }
+
                 $this->image->setOption( 'jpeg:fancy-upsampling', 'off' );
             }
@@ -359 +362 @@
             }
 
-            /**
+            /*
              * If alpha channel is not defined, set it opaque.
              *
@@ -365 +368 @@
              * has been compiled against ImageMagick version 6.4.0 or newer.
              */
-            if ( method_exists( $this->image, 'getImageAlphaChannel') && $this->image->getImageAlphaChannel() === Imagick::ALPHACHANNEL_UNDEFINED ) {
-                $this->image->setImageAlphaChannel( Imagick::ALPHACHANNEL_OPAQUE );
-            }
-
-            // Limit the  bit depth of resized images to 8 bits per channel.
-            if ( 8 < $this->image->getImageDepth() ) {
-                $this->image->setImageDepth( 8 );
-            }
-
-            $this->image->setInterlaceScheme( Imagick::INTERLACE_NO );
+            if ( is_callable( array( $this->image, 'getImageAlphaChannel' ) )
+                && is_callable( array( $this->image, 'setImageAlphaChannel' ) )
+                && defined( Imagick::ALPHACHANNEL_UNDEFINED )
+                && defined( Imagick::ALPHACHANNEL_OPAQUE )
+            ) {
+                if ( $this->image->getImageAlphaChannel() === Imagick::ALPHACHANNEL_UNDEFINED ) {
+                    $this->image->setImageAlphaChannel( Imagick::ALPHACHANNEL_OPAQUE );
+                }
+            }
+
+            // Limit the bit depth of resized images to 8 bits per channel.
+            if ( is_callable( array( $this->image, 'getImageDepth' ) ) && is_callable( array( $this->image, 'setImageDepth' ) ) ) {
+                if ( 8 < $this->image->getImageDepth() ) {
+                    $this->image->setImageDepth( 8 );
+                }
+            }
+
+            if ( is_callable( array( $this->image, 'setInterlaceScheme' ) ) && defined( 'Imagick::INTERLACE_NO' ) ) {
+                $this->image->setInterlaceScheme( Imagick::INTERLACE_NO );
+            }
 
         }
@@ -663 +676 @@
      */
     protected function strip_meta() {
+
+        if ( ! is_callable( array( $this->image, 'getImageProfiles' ) ) ) {
+            return new WP_Error( 'image_strip_meta_error', __('Imagick::getImageProfiles() is required to strip image meta.') );
+        }
+
+        if ( ! is_callable( array( $this->image, 'removeImageProfile' ) ) ) {
+            return new WP_Error( 'image_strip_meta_error', __('Imagick::removeImageProfile() is required to strip image meta.') );
+        }
+
+        /*
+         * Protect a few profiles from being stripped for the following reasons:
+         *
+         * - icc:  Color profile information
+         * - icm:  Color profile information
+         * - iptc: Copyright data
+         * - exif: Orientation data
+         * - xmp:  Rights usage data
+         */
+        $protected_profiles = array(
+            'icc',
+            'icm',
+            'iptc',
+            'exif',
+            'xmp',
+        );
+
         try {
             // Strip profiles.
             foreach ( $this->image->getImageProfiles( '*', true ) as $key => $value ) {
-                if ( $key != 'icc' && $key != 'icm' ) {
+                if ( ! in_array( $key, $protected_profiles ) ) {
                     $this->image->removeImageProfile( $key );
                 }
             }
 
-            // Strip image properties.
-            if ( method_exists( $this->image, 'deleteImageProperty' ) ) {
-                $this->image->deleteImageProperty( 'comment' );
-                $this->image->deleteImageProperty( 'Thumb::URI' );
-                $this->image->deleteImageProperty( 'Thumb::MTime' );
-                $this->image->deleteImageProperty( 'Thumb::Size' );
-                $this->image->deleteImageProperty( 'Thumb::Mimetype' );
-                $this->image->deleteImageProperty( 'software' );
-                $this->image->deleteImageProperty( 'Thumb::Image::Width' );
-                $this->image->deleteImageProperty( 'Thumb::Image::Height' );
-                $this->image->deleteImageProperty( 'Thumb::Document::Pages' );
-            } else {
-                $this->image->setImageProperty( 'comment', '' );
-                $this->image->setImageProperty( 'Thumb::URI', '' );
-                $this->image->setImageProperty( 'Thumb::MTime', '' );
-                $this->image->setImageProperty( 'Thumb::Size', '' );
-                $this->image->setImageProperty( 'Thumb::Mimetype', '' );
-                $this->image->setImageProperty( 'software', '' );
-                $this->image->setImageProperty( 'Thumb::Image::Width', '' );
-                $this->image->setImageProperty( 'Thumb::Image::Height', '' );
-                $this->image->setImageProperty( 'Thumb::Document::Pages', '' );
-            }
         } catch ( Exception $e ) {
             return new WP_Error( 'image_strip_meta_error', $e->getMessage() );