Media: Reset Exif orientation after rotate in WP_Image_Editor_Imagick.

Due to inconsistencies in the way browsers handle Exif orientation data,
if a user manually rotates an image within WordPress, set the Exif orientation to
the default (1) so that the image displays with the same rotation/flip in every browser.

Props sanchothefat, triplejumper12, joemcgill, azaozz, markoheijnen, mikeschroder.
Merges [40123] and [40129] to the 4.7 branch.
Fixes #37140. See #14459.


git-svn-id: https://develop.svn.wordpress.org/branches/4.7@40135 602fd350-edb4-49c9-b593-d223f7449a82

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

@@ -549,6 +549,11 @@ class WP_Image_Editor_Imagick extends WP_Image_Editor {
 		try {
 			$this->image->rotateImage( new ImagickPixel('none'), 360-$angle );
 
+			// Normalise Exif orientation data so that display is consistent across devices.
+			if ( is_callable( array( $this->image, 'setImageOrientation' ) ) && defined( 'Imagick::ORIENTATION_TOPLEFT' ) ) {
+				$this->image->setImageOrientation( Imagick::ORIENTATION_TOPLEFT );
+			}
+
 			// Since this changes the dimensions of the image, update the size.
 			$result = $this->update_size();
 			if ( is_wp_error( $result ) )

tests/phpunit/tests/image/editor_imagick.php

@@ -542,4 +542,34 @@ class Tests_Image_Editor_Imagick extends WP_Image_UnitTestCase {
 
 		$this->assertTrue( $result );
 	}
+
+	/**
+	 * Test resetting Exif orientation data on rotate
+	 *
+	 * @ticket 37140
+	 */
+	public function test_remove_orientation_data_on_rotate() {
+		$file = DIR_TESTDATA . "/images/test-image-upside-down.jpg";
+		$data = wp_read_image_metadata( $file );
+
+		// The orientation value 3 is equivalent to rotated upside down (180 degrees).
+		$this->assertEquals( 3, intval( $data['orientation'] ), 'Orientation value read from does not match image file Exif data: ' . $file );
+
+		$temp_file = wp_tempnam( $file );
+		$image = wp_get_image_editor( $file );
+
+		// Test a value that would not lead back to 1, as WP is resetting the value to 1 manually.
+		$image->rotate( 90 );
+		$ret = $image->save( $temp_file, 'image/jpeg' );
+
+		$data = wp_read_image_metadata( $ret['path'] );
+
+		// Make sure the image is no longer in The Upside Down Exif orientation.
+		$this->assertEquals( 1, intval( $data['orientation'] ), 'Orientation Exif data was not updated after rotating image: ' . $file );
+
+		// Remove both the generated file ending in .tmp and tmp.jpg due to wp_tempnam().
+		unlink( $temp_file );
+		unlink( $ret['path'] );
+	}
+
 }