diff --git a/src/media/media_decoder.cpp b/src/media/media_decoder.cpp
index 992b80051a3258c63d8fb47b0b050a9dfd448c2d..9ebc6ea562d109e5b202d6e0269c880fd5b9b2d6 100644
--- a/src/media/media_decoder.cpp
+++ b/src/media/media_decoder.cpp
@@ -76,7 +76,7 @@ int MediaDecoder::openInput(const DeviceParams& params)
     inputParams_ = params;
     AVInputFormat *iformat = av_find_input_format(params.format.c_str());
 
-    if (!iformat)
+    if (!iformat && !params.format.empty())
         RING_WARN("Cannot find format \"%s\"", params.format.c_str());
 
     if (params.width and params.height) {