diff --git a/src/pngchunk.cpp b/src/pngchunk.cpp
index 561dc1a0..929b974b 100644
--- a/src/pngchunk.cpp
+++ b/src/pngchunk.cpp
@@ -400,7 +400,7 @@ namespace Exiv2 {
             && memcmp("Description", key, 11) == 0
             && pImage->comment().empty())
         {
-            pImage->comment().assign(reinterpret_cast<char*>(arr.pData_), arr.size_);
+            pImage->setComment(std::string(reinterpret_cast<char*>(arr.pData_), arr.size_));
         }
 
     } // PngChunk::parseChunkContent