diff --git a/trunk/research/librtmp/srs_flv_codec.h b/trunk/research/librtmp/srs_flv_codec.h
deleted file mode 100644
index 838df5034..000000000
--- a/trunk/research/librtmp/srs_flv_codec.h
+++ /dev/null
@@ -1,147 +0,0 @@
-/*
-The MIT License (MIT)
-
-Copyright (c) 2013-2014 winlin
-
-Permission is hereby granted, free of charge, to any person obtaining a copy of
-this software and associated documentation files (the "Software"), to deal in
-the Software without restriction, including without limitation the rights to
-use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
-the Software, and to permit persons to whom the Software is furnished to do so,
-subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
-FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
-COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
-IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
-CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-*/
-
-#ifndef SRS_RESEARH_FLV_CODEC_HPP
-#define SRS_RESEARH_FLV_CODEC_HPP
-
-/*
-#include "srs_flv_codec.h"
-*/
-
-#include <unistd.h>
-#include <fcntl.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-
-#define ERROR_FLV_CODEC_EOF 100
-
-int open_flv_file(char* in_flv_file)
-{
-    return open(in_flv_file, O_RDONLY);
-}
-
-void close_flv_file(int fd)
-{
-    if (fd > 0) {
-        close(fd);
-    }
-}
-
-int flv_open_ic(int flv_fd)
-{
-    int ret = 0;
-    
-    char h[13]; // 9+4
-    
-    if (read(flv_fd, h, sizeof(h)) != sizeof(h)) {
-        ret = -1;
-        trace("read flv header failed. ret=%d", ret);
-        return ret;
-    }
-    
-    if (h[0] != 'F' || h[1] != 'L' || h[2] != 'V') {
-        ret = -1;
-        trace("input is not a flv file. ret=%d", ret);
-        return ret;
-    }
-    
-    return ret;
-}
-
-int flv_read_packet(int flv_fd, int* type, u_int32_t* timestamp, char** data, int* size)
-{
-    int ret = 0;
-    
-    char th[11]; // tag header
-    char ts[4]; // tag size
-    
-    int32_t data_size = 0;
-    u_int32_t time = 0; 
-    
-    char* pp;
-    
-    // read tag header
-    if ((ret = read(flv_fd, th, sizeof(th))) != sizeof(th)) {
-        if (ret == 0) {
-            return ERROR_FLV_CODEC_EOF;
-        }
-        ret = -1;
-        trace("read flv tag header failed. ret=%d", ret);
-        return ret;
-    }
-    
-    // Reserved UB [2]
-    // Filter UB [1]
-    // TagType UB [5]
-    *type = (int)(th[0] & 0x1F);
-    
-    // DataSize UI24
-    pp = (char*)&data_size;
-    pp[2] = th[1];
-    pp[1] = th[2];
-    pp[0] = th[3];
-    
-    // Timestamp UI24
-    pp = (char*)&time;
-    pp[2] = th[4];
-    pp[1] = th[5];
-    pp[0] = th[6];
-    
-    // TimestampExtended UI8
-    pp[3] = th[7];
-    
-    *timestamp = time;
-    
-    // check data size.
-    if (data_size <= 0) {
-        ret = -1;
-        trace("invalid data size. size=%d, ret=%d", data_size, ret);
-        return ret;
-    }
-    
-    // read tag data.
-    *size = data_size;
-    *data = (char*)malloc(data_size);
-    if ((ret = read(flv_fd, *data, data_size)) != data_size) {
-        if (ret == 0) {
-            return ERROR_FLV_CODEC_EOF;
-        }
-        ret = -1;
-        trace("read flv tag data failed. size=%d, ret=%d", data_size, ret);
-        return ret;
-    }
-    
-    // ignore 4bytes tag size.
-    if ((ret = read(flv_fd, ts, sizeof(ts))) != sizeof(ts)) {
-        if (ret == 0) {
-            return ERROR_FLV_CODEC_EOF;
-        }
-        ret = -1;
-        trace("read flv tag size failed. ret=%d", ret);
-        return ret;
-    }
-    
-    return 0;
-}
-
-#endif
diff --git a/trunk/research/librtmp/srs_flv_injecter.c b/trunk/research/librtmp/srs_flv_injecter.c
index 445869f92..8a500b445 100644
--- a/trunk/research/librtmp/srs_flv_injecter.c
+++ b/trunk/research/librtmp/srs_flv_injecter.c
@@ -34,7 +34,8 @@ gcc srs_flv_injecter.c ../../objs/lib/srs_librtmp.a -g -O0 -lstdc++ -o srs_flv_i
 
 #include "../../objs/include/srs_librtmp.h"
 #include "srs_research_public.h"
-#include "srs_flv_codec.h"
+
+#define ERROR_INJECTED 10000
 
 int process(const char* in_flv_file, const char* out_flv_file, srs_flv_t* pic, srs_flv_t* poc);
 int inject_flv(srs_flv_t ic, srs_flv_t oc);
@@ -87,7 +88,12 @@ int main(int argc, char** argv)
     
     if (ret != 0) {
         unlink(tmp_file);
-        trace("error, remove tmp file.");
+        if (ret == ERROR_INJECTED) {
+            ret = 0;
+            trace("file already injected.");
+        } else {
+            trace("error, remove tmp file.");
+        }
     } else {
         rename(tmp_file, out_flv_file);
         trace("completed, rename to %s", out_flv_file);
@@ -153,22 +159,118 @@ int inject_flv(srs_flv_t ic, srs_flv_t oc)
     u_int32_t timestamp = 0;
     char* data = NULL;
     int32_t size;
+    int64_t offset = 0;
     
     // metadata
     srs_amf0_t amf0_name = NULL;
+    int amf0_name_size = 0;
     srs_amf0_t amf0_data = NULL;
+    srs_amf0_t keyframes = NULL;
+    srs_amf0_t filepositions = NULL;
+    srs_amf0_t times = NULL;
     
     // reset to generate metadata
     srs_flv_lseek(ic, 0);
     
-    if ((ret = srs_flv_read_header(oc, header)) != 0) {
+    if ((ret = srs_flv_read_header(ic, header)) != 0) {
         return ret;
     }
     
-    trace("start inject flv");
+    trace("build keyframe infos from flv");
+    for (;;) {
+        offset = srs_flv_tellg(ic);
+        
+        // tag header
+        if ((ret = srs_flv_read_tag_header(ic, &type, &size, &timestamp)) != 0) {
+            if (srs_flv_is_eof(ret)) {
+                trace("parse completed.");
+                break;
+            }
+            trace("flv get packet failed. ret=%d", ret);
+            return ret;
+        }
+        
+        if (size <= 0) {
+            trace("invalid size=%d", size);
+            break;
+        }
+        
+        // TODO: FIXME: mem leak when error.
+        data = (char*)malloc(size);
+        if ((ret = srs_flv_read_tag_data(ic, data, size)) != 0) {
+            return ret;
+        }
+        
+        // data tag
+        if (type == SRS_RTMP_TYPE_VIDEO) {
+            if (!srs_flv_is_sequence_header(data, size) && srs_flv_is_keyframe(data, size)) {
+                srs_amf0_strict_array_append(filepositions, srs_amf0_create_number(offset));
+                srs_amf0_strict_array_append(times, srs_amf0_create_number(((double)timestamp)/ 1000));
+            }
+        } else if (type == SRS_RTMP_TYPE_SCRIPT) {
+            if ((ret = parse_metadata(data, size, &amf0_name, &amf0_data)) != 0) {
+                return ret;
+            }
+            
+            if (srs_amf0_is_object(amf0_data)) {
+                keyframes = srs_amf0_object_property(amf0_data, "keyframes");
+                if (keyframes != NULL) {
+                    return 0;
+                }
+                keyframes = srs_amf0_create_ecma_array();
+                srs_amf0_object_property_set(amf0_data, "keyframes", keyframes);
+                filepositions = srs_amf0_create_strict_array();
+                srs_amf0_object_property_set(keyframes, "filepositions", filepositions);
+                times = srs_amf0_create_strict_array();
+                srs_amf0_object_property_set(keyframes, "times", times);
+            } else if (srs_amf0_is_ecma_array(amf0_data)) {
+                keyframes = srs_amf0_ecma_array_property(amf0_data, "keyframes");
+                if (keyframes != NULL) {
+                    return 0;
+                }
+                keyframes = srs_amf0_create_ecma_array();
+                srs_amf0_ecma_array_property_set(amf0_data, "keyframes", keyframes);
+                filepositions = srs_amf0_create_strict_array();
+                srs_amf0_ecma_array_property_set(keyframes, "filepositions", filepositions);
+                times = srs_amf0_create_strict_array();
+                srs_amf0_ecma_array_property_set(keyframes, "times", times);
+            }
+        }
+        
+        free(data);
+    }
+    
+    // reset to write injected file
+    srs_flv_lseek(ic, 0);
+    
+    if ((ret = srs_flv_read_header(ic, header)) != 0) {
+        return ret;
+    }
+    
+    if ((ret = srs_flv_write_header(oc, header)) != 0) {
+        return ret;
+    }
+    
+    // write metadata
+    if (amf0_name != NULL && amf0_data != NULL) {
+        amf0_name_size = srs_amf0_size(amf0_name);
+        size = amf0_name_size + srs_amf0_size(amf0_data);
+        data = (char*)malloc(size);
+        if ((ret = srs_amf0_serialize(amf0_name, data, amf0_name_size)) != 0) {
+            return ret;
+        }
+        if ((ret = srs_amf0_serialize(amf0_data, data + amf0_name_size, size - amf0_name_size)) != 0) {
+            return ret;
+        }
+        if ((ret = srs_flv_write_tag(oc, SRS_RTMP_TYPE_SCRIPT, 0, data, size)) != 0) {
+            return ret;
+        }
+        free(data);
+    }
+    trace("build keyframe infos from flv");
     for (;;) {
         // tag header
-        if ((ret = srs_flv_read_tag_header(oc, &type, &size, &timestamp)) != 0) {
+        if ((ret = srs_flv_read_tag_header(ic, &type, &size, &timestamp)) != 0) {
             if (srs_flv_is_eof(ret)) {
                 trace("parse completed.");
                 return 0;
@@ -184,16 +286,18 @@ int inject_flv(srs_flv_t ic, srs_flv_t oc)
         
         // TODO: FIXME: mem leak when error.
         data = (char*)malloc(size);
-        if ((ret = srs_flv_read_tag_data(oc, data, size)) != 0) {
+        if ((ret = srs_flv_read_tag_data(ic, data, size)) != 0) {
             return ret;
         }
         
         // data tag
-        if (type == SRS_RTMP_TYPE_VIDEO) {
-        } else if (type == SRS_RTMP_TYPE_SCRIPT) {
-            if ((ret = parse_metadata(data, size, &amf0_name, &amf0_data)) != 0) {
-                return ret;
-            }
+        if (type == SRS_RTMP_TYPE_SCRIPT) {
+            continue;
+        }
+        
+        // copy
+        if ((ret = srs_flv_write_tag(oc, type, timestamp, data, size)) != 0) {
+            return ret;
         }
         
         free(data);
diff --git a/trunk/research/librtmp/srs_flv_parser.c b/trunk/research/librtmp/srs_flv_parser.c
index fd8c2de97..108a483ac 100644
--- a/trunk/research/librtmp/srs_flv_parser.c
+++ b/trunk/research/librtmp/srs_flv_parser.c
@@ -34,7 +34,6 @@ gcc srs_ingest_flv.c ../../objs/lib/srs_librtmp.a -g -O0 -lstdc++ -o srs_ingest_
 
 #include "../../objs/include/srs_librtmp.h"
 #include "srs_research_public.h"
-#include "srs_flv_codec.h"
 
 int parse_flv(srs_flv_t flv);
 int main(int argc, char** argv)
diff --git a/trunk/research/librtmp/srs_ingest_flv.c b/trunk/research/librtmp/srs_ingest_flv.c
index ab3e87838..8c4c0a07e 100644
--- a/trunk/research/librtmp/srs_ingest_flv.c
+++ b/trunk/research/librtmp/srs_ingest_flv.c
@@ -34,9 +34,8 @@ gcc srs_ingest_flv.c ../../objs/lib/srs_librtmp.a -g -O0 -lstdc++ -o srs_ingest_
 
 #include "../../objs/include/srs_librtmp.h"
 #include "srs_research_public.h"
-#include "srs_flv_codec.h"
 
-int proxy(int flv_fd, srs_rtmp_t ortmp);
+int proxy(srs_flv_t flv, srs_rtmp_t ortmp);
 int connect_oc(srs_rtmp_t ortmp);
 
 #define RE_PULSE_MS 300
@@ -59,7 +58,7 @@ int main(int argc, char** argv)
     // rtmp handler
     srs_rtmp_t ortmp;
     // flv handler
-    int flv_fd;
+    srs_flv_t flv;
     
     if (argc <= 2) {
         printf("ingest flv file and publish to RTMP server\n"
@@ -94,8 +93,7 @@ int main(int argc, char** argv)
     trace("input:  %s", in_flv_file);
     trace("output: %s", out_rtmp_url);
 
-    flv_fd = open_flv_file(in_flv_file);
-    if (flv_fd <= 0) {
+    if ((flv = srs_flv_open_read(in_flv_file)) == NULL) {
         ret = 2;
         trace("open flv file failed. ret=%d", ret);
         return ret;
@@ -103,31 +101,46 @@ int main(int argc, char** argv)
     
     ortmp = srs_rtmp_create(out_rtmp_url);
 
-    ret = proxy(flv_fd, ortmp);
+    ret = proxy(flv, ortmp);
     trace("ingest flv to RTMP completed");
     
     srs_rtmp_destroy(ortmp);
-    close_flv_file(flv_fd);
+    srs_flv_close(flv);
     
     return ret;
 }
 
-int do_proxy(int flv_fd, srs_rtmp_t ortmp, int64_t re, u_int32_t* ptimestamp)
+int do_proxy(srs_flv_t flv, srs_rtmp_t ortmp, int64_t re, u_int32_t* ptimestamp)
 {
     int ret = 0;
     
     // packet data
-    int type, size;
+    char type;
+    int size;
     char* data = NULL;
     
     trace("start ingest flv to RTMP stream");
     for (;;) {
-        if ((ret = flv_read_packet(flv_fd, &type, ptimestamp, &data, &size)) != 0) {
-            trace("irtmp get packet failed. ret=%d", ret);
+        // tag header
+        if ((ret = srs_flv_read_tag_header(flv, &type, &size, ptimestamp)) != 0) {
+            if (srs_flv_is_eof(ret)) {
+                trace("parse completed.");
+                return 0;
+            }
+            trace("flv get packet failed. ret=%d", ret);
+            return ret;
+        }
+        
+        if (size <= 0) {
+            trace("invalid size=%d", size);
+            break;
+        }
+        
+        // TODO: FIXME: mem leak when error.
+        data = (char*)malloc(size);
+        if ((ret = srs_flv_read_tag_data(flv, data, size)) != 0) {
             return ret;
         }
-        verbose("irtmp got packet: type=%s, time=%d, size=%d", 
-            srs_type2string(type), timestamp, size);
         
         if ((ret = srs_write_packet(ortmp, type, *ptimestamp, data, size)) != 0) {
             trace("irtmp get packet failed. ret=%d", ret);
@@ -142,12 +155,13 @@ int do_proxy(int flv_fd, srs_rtmp_t ortmp, int64_t re, u_int32_t* ptimestamp)
     return ret;
 }
 
-int proxy(int flv_fd, srs_rtmp_t ortmp)
+int proxy(srs_flv_t flv, srs_rtmp_t ortmp)
 {
     int ret = 0;
     u_int32_t timestamp = 0;
     
-    if ((ret = flv_open_ic(flv_fd)) != 0) {
+    char header[13];
+    if ((ret = srs_flv_read_header(flv, header)) != 0) {
         return ret;
     }
     if ((ret = connect_oc(ortmp)) != 0) {
@@ -156,7 +170,7 @@ int proxy(int flv_fd, srs_rtmp_t ortmp)
     
     int64_t re = re_create();
     
-    ret = do_proxy(flv_fd, ortmp, re, &timestamp);
+    ret = do_proxy(flv, ortmp, re, &timestamp);
     
     // for the last pulse, always sleep.
     re_cleanup(re, timestamp);
diff --git a/trunk/src/kernel/srs_kernel_flv.cpp b/trunk/src/kernel/srs_kernel_flv.cpp
index 55501f2a2..60c7e313f 100644
--- a/trunk/src/kernel/srs_kernel_flv.cpp
+++ b/trunk/src/kernel/srs_kernel_flv.cpp
@@ -207,20 +207,36 @@ int SrsFlvEncoder::write_header()
         'F', 'L', 'V', // Signatures "FLV"
         (char)0x01, // File version (for example, 0x01 for FLV version 1)
         (char)0x00, // 4, audio; 1, video; 5 audio+video.
-        (char)0x00, (char)0x00, (char)0x00, (char)0x09, // DataOffset UI32 The length of this header in bytes
-        (char)0x00, (char)0x00, (char)0x00, (char)0x00// PreviousTagSize0 UI32 Always 0
+        (char)0x00, (char)0x00, (char)0x00, (char)0x09 // DataOffset UI32 The length of this header in bytes
     };
     
     // flv specification should set the audio and video flag,
     // actually in practise, application generally ignore this flag,
     // so we generally set the audio/video to 0.
     
+    // write 9bytes header.
+    if ((ret = write_header(flv_header)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    
+    return ret;
+}
+
+int SrsFlvEncoder::write_header(char flv_header[9])
+{
+    int ret = ERROR_SUCCESS;
+    
     // write data.
-    if ((ret = _fs->write(flv_header, sizeof(flv_header), NULL)) != ERROR_SUCCESS) {
+    if ((ret = _fs->write(flv_header, 9, NULL)) != ERROR_SUCCESS) {
         srs_error("write flv header failed. ret=%d", ret);
         return ret;
     }
     
+    char pts[] = { 0x00, 0x00, 0x00, 0x00 };
+    if ((ret = _fs->write(pts, 4, NULL)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    
     return ret;
 }
 
diff --git a/trunk/src/kernel/srs_kernel_flv.hpp b/trunk/src/kernel/srs_kernel_flv.hpp
index b25680352..8efd3b800 100644
--- a/trunk/src/kernel/srs_kernel_flv.hpp
+++ b/trunk/src/kernel/srs_kernel_flv.hpp
@@ -92,6 +92,7 @@ public:
     * that is, 9+4=13bytes.
     */
     virtual int write_header();
+    virtual int write_header(char flv_header[9]);
     /**
     * write flv metadata. 
     * serialize from:
diff --git a/trunk/src/libs/srs_librtmp.cpp b/trunk/src/libs/srs_librtmp.cpp
index 3f87879d7..7648d1f70 100644
--- a/trunk/src/libs/srs_librtmp.cpp
+++ b/trunk/src/libs/srs_librtmp.cpp
@@ -491,6 +491,34 @@ int srs_flv_read_tag_data(srs_flv_t flv, char* data, int32_t size)
     return ret;
 }
 
+int srs_flv_write_header(srs_flv_t flv, char header[9])
+{
+    int ret = ERROR_SUCCESS;
+    
+    FlvContext* context = (FlvContext*)flv;
+    if ((ret = context->enc.write_header(header)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    
+    return ret;
+}
+
+int srs_flv_write_tag(srs_flv_t flv, char type, int32_t time, char* data, int size)
+{
+    int ret = ERROR_SUCCESS;
+    
+    FlvContext* context = (FlvContext*)flv;
+    if (type == SRS_RTMP_TYPE_AUDIO) {
+        return context->enc.write_audio(time, data, size);
+    } else if (type == SRS_RTMP_TYPE_VIDEO) {
+        return context->enc.write_video(time, data, size);
+    } else {
+        return context->enc.write_metadata(data, size);
+    }
+
+    return ret;
+}
+
 int64_t srs_flv_tellg(srs_flv_t flv)
 {
     FlvContext* context = (FlvContext*)flv;
@@ -508,6 +536,16 @@ flv_bool srs_flv_is_eof(int error_code)
     return error_code == ERROR_SYSTEM_FILE_EOF;
 }
 
+flv_bool srs_flv_is_sequence_header(char* data, int32_t size)
+{
+    return SrsCodec::video_is_sequence_header((int8_t*)data, (int)size);
+}
+
+flv_bool srs_flv_is_keyframe(char* data, int32_t size)
+{
+    return SrsCodec::video_is_keyframe((int8_t*)data, (int)size);
+}
+
 srs_amf0_t srs_amf0_parse(char* data, int size, int* nparsed)
 {
     int ret = ERROR_SUCCESS;
@@ -536,6 +574,21 @@ srs_amf0_t srs_amf0_parse(char* data, int size, int* nparsed)
     return amf0;
 }
 
+srs_amf0_t srs_amf0_create_number(amf0_number value)
+{
+    return SrsAmf0Any::number(value);
+}
+
+srs_amf0_t srs_amf0_create_ecma_array()
+{
+    return SrsAmf0Any::ecma_array();
+}
+
+srs_amf0_t srs_amf0_create_strict_array()
+{
+    return SrsAmf0Any::strict_array();
+}
+
 void srs_amf0_free(srs_amf0_t amf0)
 {
     SrsAmf0Any* any = (SrsAmf0Any*)amf0;
@@ -547,6 +600,30 @@ void srs_amf0_free_bytes(char* data)
     srs_freep(data);
 }
 
+int srs_amf0_size(srs_amf0_t amf0)
+{
+    SrsAmf0Any* any = (SrsAmf0Any*)amf0;
+    return any->total_size();
+}
+
+int srs_amf0_serialize(srs_amf0_t amf0, char* data, int size)
+{
+    int ret = ERROR_SUCCESS;
+    
+    SrsAmf0Any* any = (SrsAmf0Any*)amf0;
+    
+    SrsStream stream;
+    if ((ret = stream.initialize(data, size)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    
+    if ((ret = any->write(&stream)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    
+    return ret;
+}
+
 amf0_bool srs_amf0_is_string(srs_amf0_t amf0)
 {
     SrsAmf0Any* any = (SrsAmf0Any*)amf0;
@@ -625,6 +702,19 @@ srs_amf0_t srs_amf0_object_property_value_at(srs_amf0_t amf0, int index)
     return (srs_amf0_t)obj->value_at(index);
 }
 
+srs_amf0_t srs_amf0_object_property(srs_amf0_t amf0, const char* name)
+{
+    SrsAmf0Object* obj = (SrsAmf0Object*)amf0;
+    return (srs_amf0_t)obj->get_property(name);
+}
+
+void srs_amf0_object_property_set(srs_amf0_t amf0, const char* name, srs_amf0_t value)
+{
+    SrsAmf0Object* obj = (SrsAmf0Object*)amf0;
+    SrsAmf0Any* any = (SrsAmf0Any*)value;
+    obj->set(name, any);
+}
+
 int srs_amf0_ecma_array_property_count(srs_amf0_t amf0)
 {
     SrsAmf0EcmaArray * obj = (SrsAmf0EcmaArray*)amf0;
@@ -643,16 +733,36 @@ srs_amf0_t srs_amf0_ecma_array_property_value_at(srs_amf0_t amf0, int index)
     return (srs_amf0_t)obj->value_at(index);
 }
 
+srs_amf0_t srs_amf0_ecma_array_property(srs_amf0_t amf0, const char* name)
+{
+    SrsAmf0EcmaArray* obj = (SrsAmf0EcmaArray*)amf0;
+    return (srs_amf0_t)obj->get_property(name);
+}
+
+void srs_amf0_ecma_array_property_set(srs_amf0_t amf0, const char* name, srs_amf0_t value)
+{
+    SrsAmf0EcmaArray* obj = (SrsAmf0EcmaArray*)amf0;
+    SrsAmf0Any* any = (SrsAmf0Any*)value;
+    obj->set(name, any);
+}
+
 int srs_amf0_strict_array_property_count(srs_amf0_t amf0)
 {
-    SrsAmf0EcmaArray * obj = (SrsAmf0EcmaArray*)amf0;
+    SrsAmf0StrictArray * obj = (SrsAmf0StrictArray*)amf0;
     return obj->count();
 }
 
 srs_amf0_t srs_amf0_strict_array_property_at(srs_amf0_t amf0, int index)
 {
-    SrsAmf0EcmaArray* obj = (SrsAmf0EcmaArray*)amf0;
-    return (srs_amf0_t)obj->value_at(index);
+    SrsAmf0StrictArray* obj = (SrsAmf0StrictArray*)amf0;
+    return (srs_amf0_t)obj->at(index);
+}
+
+void srs_amf0_strict_array_append(srs_amf0_t amf0, srs_amf0_t value)
+{
+    SrsAmf0StrictArray* obj = (SrsAmf0StrictArray*)amf0;
+    SrsAmf0Any* any = (SrsAmf0Any*)value;
+    obj->append(any);
 }
 
 void __srs_fill_level_spaces(stringstream& ss, int level)
@@ -735,10 +845,14 @@ char* srs_amf0_human_print(srs_amf0_t amf0, char** pdata, int* psize)
     memcpy(data, str.data(), str.length());
     data[str.length()] = 0;
     
-    *pdata = data;
-    *psize = str.length();
+    if (pdata) {
+        *pdata = data;
+    }
+    if (psize) {
+        *psize = str.length();
+    }
     
-    return *pdata;
+    return data;
 }
 
 #ifdef __cplusplus
diff --git a/trunk/src/libs/srs_librtmp.hpp b/trunk/src/libs/srs_librtmp.hpp
index 59ce79362..d3bd5fde8 100644
--- a/trunk/src/libs/srs_librtmp.hpp
+++ b/trunk/src/libs/srs_librtmp.hpp
@@ -165,12 +165,23 @@ int srs_flv_read_header(srs_flv_t flv, char header[9]);
 int srs_flv_read_tag_header(srs_flv_t flv, char* ptype, int32_t* pdata_size, u_int32_t* ptime);
 /* read the tag data. drop the 4bytes previous tag size */
 int srs_flv_read_tag_data(srs_flv_t flv, char* data, int32_t size);
+/* write flv header to file, auto write the 4bytes zero previous tag size. */
+int srs_flv_write_header(srs_flv_t flv, char header[9]);
+/* write flv tag to file, auto write the 4bytes previous tag size */
+int srs_flv_write_tag(srs_flv_t flv, char type, int32_t time, char* data, int size);
+/* file stream */
 /* file stream tellg to get offset */
 int64_t srs_flv_tellg(srs_flv_t flv);
 /* seek file stream, offset is form the start of file */
 void srs_flv_lseek(srs_flv_t flv, int64_t offset);
+/* error code */
 /* whether the error code indicates EOF */
 flv_bool srs_flv_is_eof(int error_code);
+/* media codec */
+/* whether the video body is sequence header */
+flv_bool srs_flv_is_sequence_header(char* data, int32_t size);
+/* whether the video body is keyframe */
+flv_bool srs_flv_is_keyframe(char* data, int32_t size);
 
 /**
 * amf0 codec
@@ -180,8 +191,14 @@ typedef void* srs_amf0_t;
 typedef int amf0_bool;
 typedef double amf0_number;
 srs_amf0_t srs_amf0_parse(char* data, int size, int* nparsed);
+srs_amf0_t srs_amf0_create_number(amf0_number value);
+srs_amf0_t srs_amf0_create_ecma_array();
+srs_amf0_t srs_amf0_create_strict_array();
 void srs_amf0_free(srs_amf0_t amf0);
 void srs_amf0_free_bytes(char* data);
+/* size and to bytes */
+int srs_amf0_size(srs_amf0_t amf0);
+int srs_amf0_serialize(srs_amf0_t amf0, char* data, int size);
 /* type detecter */
 amf0_bool srs_amf0_is_string(srs_amf0_t amf0);
 amf0_bool srs_amf0_is_boolean(srs_amf0_t amf0);
@@ -198,13 +215,18 @@ amf0_number srs_amf0_to_number(srs_amf0_t amf0);
 int srs_amf0_object_property_count(srs_amf0_t amf0);
 const char* srs_amf0_object_property_name_at(srs_amf0_t amf0, int index);
 srs_amf0_t srs_amf0_object_property_value_at(srs_amf0_t amf0, int index);
+srs_amf0_t srs_amf0_object_property(srs_amf0_t amf0, const char* name);
+void srs_amf0_object_property_set(srs_amf0_t amf0, const char* name, srs_amf0_t value);
 /* ecma array value converter */
 int srs_amf0_ecma_array_property_count(srs_amf0_t amf0);
 const char* srs_amf0_ecma_array_property_name_at(srs_amf0_t amf0, int index);
 srs_amf0_t srs_amf0_ecma_array_property_value_at(srs_amf0_t amf0, int index);
+srs_amf0_t srs_amf0_ecma_array_property(srs_amf0_t amf0, const char* name);
+void srs_amf0_ecma_array_property_set(srs_amf0_t amf0, const char* name, srs_amf0_t value);
 /* strict array value converter */
 int srs_amf0_strict_array_property_count(srs_amf0_t amf0);
 srs_amf0_t srs_amf0_strict_array_property_at(srs_amf0_t amf0, int index);
+void srs_amf0_strict_array_append(srs_amf0_t amf0, srs_amf0_t value);
 /**
 * human readable print 
 * @param pdata, output the heap data, 
diff --git a/trunk/src/rtmp/srs_protocol_amf0.cpp b/trunk/src/rtmp/srs_protocol_amf0.cpp
index 74d664f1b..716f4ce16 100644
--- a/trunk/src/rtmp/srs_protocol_amf0.cpp
+++ b/trunk/src/rtmp/srs_protocol_amf0.cpp
@@ -1113,6 +1113,11 @@ SrsAmf0Any* SrsAmf0StrictArray::at(int index)
     return properties.at(index);
 }
 
+void SrsAmf0StrictArray::append(SrsAmf0Any* any)
+{
+    properties.push_back(any);
+}
+
 int SrsAmf0Size::utf8(string value)
 {
     return 2 + value.length();
diff --git a/trunk/src/rtmp/srs_protocol_amf0.hpp b/trunk/src/rtmp/srs_protocol_amf0.hpp
index 0ad88e2cf..df8401958 100644
--- a/trunk/src/rtmp/srs_protocol_amf0.hpp
+++ b/trunk/src/rtmp/srs_protocol_amf0.hpp
@@ -260,6 +260,7 @@ public:
     virtual int count();
     // @remark: max index is count().
     virtual SrsAmf0Any* at(int index);
+    virtual void append(SrsAmf0Any* any);
 };
 
 /**