diff --git a/trunk/research/librtmp/srs_ingest_rtmp.c b/trunk/research/librtmp/srs_ingest_rtmp.c
index d4c8606cd..c0db88f91 100644
--- a/trunk/research/librtmp/srs_ingest_rtmp.c
+++ b/trunk/research/librtmp/srs_ingest_rtmp.c
@@ -127,6 +127,12 @@ int proxy(srs_rtmp_t irtmp, srs_rtmp_t ortmp)
             return ret;
         }
         
+        if (!srs_utils_flv_tag_is_ok(type)) {
+            srs_human_trace("ignore invalid flv tag=%d, dts=%d, %d bytes", type, timestamp, size);
+            free(data);
+            continue;
+        }
+        
         if ((ret = srs_human_print_rtmp_packet(type, timestamp, data, size)) != 0) {
             srs_human_trace("print packet failed. ret=%d", ret);
             return ret;
diff --git a/trunk/src/libs/srs_librtmp.cpp b/trunk/src/libs/srs_librtmp.cpp
index b2c623718..dffd90149 100644
--- a/trunk/src/libs/srs_librtmp.cpp
+++ b/trunk/src/libs/srs_librtmp.cpp
@@ -1973,6 +1973,11 @@ int srs_utils_parse_timestamp(
     
     return ret;
 }
+    
+srs_bool srs_utils_flv_tag_is_ok(char type)
+{
+    return type == SRS_RTMP_TYPE_AUDIO || type == SRS_RTMP_TYPE_VIDEO || type == SRS_RTMP_TYPE_SCRIPT;
+}
 
 char srs_utils_flv_video_codec_id(char* data, int size)
 {
@@ -2324,7 +2329,7 @@ int srs_human_print_rtmp_packet(char type, u_int32_t timestamp, char* data, int
         );
     } else if (type == SRS_RTMP_TYPE_SCRIPT) {
         srs_human_verbose("Data packet type=%s, time=%d, size=%d", 
-            srs_human_flv_tag_type2string(type), timestamp, size);
+        srs_human_flv_tag_type2string(type), timestamp, size);
         int nparsed = 0;
         while (nparsed < size) {
             int nb_parsed_this = 0;
@@ -2332,7 +2337,7 @@ int srs_human_print_rtmp_packet(char type, u_int32_t timestamp, char* data, int
             if (amf0 == NULL) {
                 break;
             }
-            
+    
             nparsed += nb_parsed_this;
             
             char* amf0_str = NULL;
diff --git a/trunk/src/libs/srs_librtmp.hpp b/trunk/src/libs/srs_librtmp.hpp
index 744575112..aee8b7a9f 100644
--- a/trunk/src/libs/srs_librtmp.hpp
+++ b/trunk/src/libs/srs_librtmp.hpp
@@ -655,6 +655,12 @@ extern int srs_utils_parse_timestamp(
     u_int32_t time, char type, char* data, int size,
     u_int32_t* ppts
 );
+    
+/**
+ * whether the flv tag specified by param type is ok.
+ * @return true when tag is video/audio/script-data; otherwise, false.
+ */
+extern srs_bool srs_utils_flv_tag_is_ok(char type);
 
 /**
 * get the CodecID of video tag.