diff --git a/conv/block_stego.cc b/conv/block_stego.cc
index 22da37e..dfc1c7d 100644
--- a/conv/block_stego.cc
+++ b/conv/block_stego.cc
@@ -57,6 +57,10 @@ Positional<std::string> src {
   parser, "path", "source video file path",
 };
 
+ValueFlag<int32_t> bitrate {
+  parser, "bitrate", "bitrate of stego video", {"bitrate"}, 5000*1000,
+};
+
 // from stdin
 std::vector<std::vector<int32_t>> indices;
 
@@ -177,11 +181,11 @@ static void Exec() {
   Enforce(0 == WelsCreateSVCEncoder(&enc), "encoder creation failure");
 
   SEncParamBase encp = {};
-  encp.iUsageType     = SCREEN_CONTENT_REAL_TIME;
+  encp.iUsageType     = CAMERA_VIDEO_REAL_TIME;
   encp.fMaxFrameRate  = fps;
   encp.iPicWidth      = w;
   encp.iPicHeight     = h;
-  encp.iTargetBitrate = 5000000;
+  encp.iTargetBitrate = args::get(param::bitrate);
   Enforce(0 == enc->Initialize(&encp), "encoder init failure");
 
   int enclv = WELS_LOG_INFO;