message: select correct MediaType in MSMF backend.
diff: @@ -347,6 +347,12 @@ struct MediaType
  }
  return false;
  }
  + bool VideoIsAvailable() const
  + {
  + return ((subType == MFVideoFormat_RGB32) ||
  + (subType == MFVideoFormat_RGB24) ||
  + (subType == MFVideoFormat_YUY2));
  + }
  };
  void printFormat(std::ostream& out, const GUID& fmt)
  @@ -627,7 +633,7 @@ public:
  {
  if (i->second.majorType == MFMediaType_Video)
  {
  - if (best.second.isEmpty() || i->second.VideoIsBetterThan(best.second, newType))
  + if (best.second.isEmpty() || (i->second.VideoIsBetterThan(best.second, newType) && i->second.VideoIsAvailable()))
  {
  best = *i;
  }
  