From 0b0ea3d8d9b9576c0a6615aa8c6e6503eca6f818 Mon Sep 17 00:00:00 2001
From: Jonas Meurer <jonas@freesources.org>
Date: Wed, 2 Feb 2022 11:57:17 +0100
Subject: [PATCH] Fix preview generation for office documents

`new \imagick` returns an object, but we need the image blob (binary
string) from this object.

This is a partial backport of #26531, which brings a lot of refactoring
but also contains the fix.

Fixes: #29956

Signed-off-by: Jonas Meurer <jonas@freesources.org>
---
 lib/private/Preview/Office.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/private/Preview/Office.php b/lib/private/Preview/Office.php
index fef218823e21d..50c016737ece9 100644
--- a/lib/private/Preview/Office.php
+++ b/lib/private/Preview/Office.php
@@ -74,7 +74,7 @@ public function getThumbnail(File $file, int $maxX, int $maxY): ?IImage {
 		}
 
 		$image = new \OC_Image();
-		$image->loadFromData($png);
+		$image->loadFromData((string) $png);
 
 		$this->cleanTmpFiles();
 		unlink($pngPreview);