Ticket #48853: 48853.2.diff

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

@@ -140 +140 @@
                 try {
                         $this->image    = new Imagick();
                         $file_extension = strtolower( pathinfo( $this->file, PATHINFO_EXTENSION ) );
-                        $filename       = $this->file;
 
                         if ( 'pdf' === $file_extension ) {
-                                $filename = $this->pdf_setup();
+                                $pdf_loaded = $this->pdf_load_source();
+
+                                if ( is_wp_error( $pdf_loaded ) ) {
+                                        return $pdf_loaded;
+                                }
+                        } else {
+                                $this->image->readImage( $this->file );
                         }
 
-                        // Reading image after Imagick instantiation because `setResolution`
-                        // only applies correctly before the image is read.
-                        $this->image->readImage( $filename );
-
                         if ( ! $this->image->valid() ) {
                                 return new WP_Error( 'invalid_image', __( 'File is not an image.' ), $this->file );
                         }
@@ -165 +166 @@
                 }
 
                 $updated_size = $this->update_size();
+
                 if ( is_wp_error( $updated_size ) ) {
                         return $updated_size;
                 }
@@ -785 +787 @@
          * Increases rendering DPI and only loads first page.
          *
          * @since 4.7.0
+         * @deprecated 5.5.0 use WP_Image_Editor_Imagick::pdf_load_source() that also loads the source.
          *
          * @return string|WP_Error File to load or WP_Error on failure.
          */
         protected function pdf_setup() {
+                _deprecated_function( __FUNCTION__, '5.5.0', 'WP_Image_Editor_Imagick::pdf_load_source()' );
+
                 try {
                         // By default, PDFs are rendered in a very low resolution.
                         // We want the thumbnail to be readable, so increase the rendering DPI.
@@ -805 +810 @@
                 }
         }
 
+        /**
+         * Sets up Imagick for PDF processing and load the image outputted by `gs`.
+         * Increases rendering DPI and only loads first page.
+         *
+         * @since 5.5.0
+         *
+         * @return true|WP_Error True on success, WP_Error on failure.
+         */
+        protected function pdf_load_source() {
+                // By default, PDFs are rendered in a very low resolution.
+                // We want the thumbnail to be readable, so increase the rendering DPI.
+                // (`setResolution` has to be done before the image is loaded.)
+                $this->image->setResolution( 128, 128 );
+
+                try {
+                        // When generating thumbnails from cropped PDF pages, Imagemagick uses the uncropped
+                        // area (resulting in unnecessary whitespace) unless the following option is set.
+                        $this->image->setOption( 'pdf:use-cropbox', true );
+
+                        // Only load the first page.
+                        $this->image->readImage( $this->file . '[0]' );
+                } catch ( Exception $e ) {
+                        try {
+                                // Attempt to run `gs` without the `use-cropbox` option.
+                                // This is a workaround for a bug in GNU Ghostscript 8.7 (and possibly other old versions)
+                                // that may prevent processing of some PDF files when `use-cropbox` is set. See #48853.
+                                $this->image->setOption( 'pdf:use-cropbox', false );
+                                $this->image->readImage( $this->file . '[0]' );
+                        } catch ( Exception $ex ) {
+                                return new WP_Error( 'pdf_setup_failed', $ex->getMessage(), $this->file );
+                        }
+                }
+
+                return true;
+        }
+
 }