All a slide into the MainWindow toolbar

source/InputStream.cpp

@@ -291,7 +291,7 @@ Void InputStream::seekInput( Int new_frame_num )
     UInt64 frame_bytes_input = m_uiWidth * m_uiHeight * 1.5;
     UInt64 nbytes_seek = frame_bytes_input * new_frame_num;
     fseek( m_pFile, nbytes_seek, SEEK_SET );
-    m_iCurrFrameNum = new_frame_num;
+    m_iCurrFrameNum = new_frame_num - 1;
   }
 }