diff --git a/ffmpegthumbnailer/moviedecoder.cpp b/ffmpegthumbnailer/moviedecoder.cpp
--- a/ffmpegthumbnailer/moviedecoder.cpp
+++ b/ffmpegthumbnailer/moviedecoder.cpp
@@ -60,6 +60,8 @@
     m_lastHeight = -1;
     m_lastPixfmt = AV_PIX_FMT_NONE;
 
+    av_register_all();
+
     QFileInfo fileInfo(filename);
 
     if ((!m_FormatContextWasGiven) && avformat_open_input(&m_pFormatContext, fileInfo.absoluteFilePath().toLocal8Bit().data(), NULL, NULL) != 0) {