for #293, add aac encoder for http aac stream.

@@ -365,7 +365,7 @@ MODULE_DEPENDS=("CORE")
 ModuleLibIncs=(${SRS_OBJS_DIR})
 ModuleLibIncs=(${SRS_OBJS_DIR})
 MODULE_FILES=("srs_kernel_error" "srs_kernel_log" "srs_kernel_stream"
 MODULE_FILES=("srs_kernel_error" "srs_kernel_log" "srs_kernel_stream"
         "srs_kernel_utility" "srs_kernel_flv" "srs_kernel_codec" "srs_kernel_file" 
         "srs_kernel_utility" "srs_kernel_flv" "srs_kernel_codec" "srs_kernel_file" 
-        "srs_kernel_consts")
+        "srs_kernel_consts" "srs_kernel_aac")
 KERNEL_INCS="src/kernel"; MODULE_DIR=${KERNEL_INCS} . auto/modules.sh
 KERNEL_INCS="src/kernel"; MODULE_DIR=${KERNEL_INCS} . auto/modules.sh
 KERNEL_OBJS="${MODULE_OBJS[@]}"
 KERNEL_OBJS="${MODULE_OBJS[@]}"
 #
 #

@@ -371,7 +371,7 @@ int SrsGoHttpFileServer::serve_file(ISrsGoHttpResponseWriter* w, SrsHttpMessage*
     }
     }
     
     
     if (true) {
     if (true) {
-        ssize_t pos;
+        size_t pos;
         std::string ext = fullpath;
         std::string ext = fullpath;
         if ((pos = ext.rfind(".")) != string::npos) {
         if ((pos = ext.rfind(".")) != string::npos) {
             ext = ext.substr(pos);
             ext = ext.substr(pos);

@@ -44,6 +44,7 @@ using namespace std;
 #include <srs_protocol_rtmp.hpp>
 #include <srs_protocol_rtmp.hpp>
 #include <srs_app_source.hpp>
 #include <srs_app_source.hpp>
 #include <srs_protocol_msg_array.hpp>
 #include <srs_protocol_msg_array.hpp>
+#include <srs_kernel_aac.hpp>
 
 
 SrsVodStream::SrsVodStream(string root_dir)
 SrsVodStream::SrsVodStream(string root_dir)
     : SrsGoHttpFileServer(root_dir)
     : SrsGoHttpFileServer(root_dir)
@@ -138,35 +139,120 @@ int SrsVodStream::serve_flv_stream(ISrsGoHttpResponseWriter* w, SrsHttpMessage*
     return ret;
     return ret;
 }
 }
 
 
-SrsFlvStreamWriter::SrsFlvStreamWriter(ISrsGoHttpResponseWriter* w)
+ISrsStreamEncoder::ISrsStreamEncoder()
+{
+}
+
+ISrsStreamEncoder::~ISrsStreamEncoder()
+{
+}
+
+SrsFlvStreamEncoder::SrsFlvStreamEncoder()
+{
+    enc = new SrsFlvEncoder();
+}
+
+SrsFlvStreamEncoder::~SrsFlvStreamEncoder()
+{
+    srs_freep(enc);
+}
+
+int SrsFlvStreamEncoder::initialize(SrsFileWriter* w)
+{
+    int ret = ERROR_SUCCESS;
+    
+    if ((ret = enc->initialize(w)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    
+    // write flv header.
+    if ((ret = enc->write_header())  != ERROR_SUCCESS) {
+        return ret;
+    }
+    
+    return ret;
+}
+
+int SrsFlvStreamEncoder::write_audio(int64_t timestamp, char* data, int size)
+{
+    return enc->write_audio(timestamp, data, size);
+}
+
+int SrsFlvStreamEncoder::write_video(int64_t timestamp, char* data, int size)
+{
+    return enc->write_video(timestamp, data, size);
+}
+
+int SrsFlvStreamEncoder::write_metadata(int64_t timestamp, char* data, int size)
+{
+    return enc->write_metadata(timestamp, data, size);
+}
+
+SrsAacStreamEncoder::SrsAacStreamEncoder()
+{
+    enc = new SrsAacEncoder();
+}
+
+SrsAacStreamEncoder::~SrsAacStreamEncoder()
+{
+    srs_freep(enc);
+}
+
+int SrsAacStreamEncoder::initialize(SrsFileWriter* w)
+{
+    int ret = ERROR_SUCCESS;
+    
+    if ((ret = enc->initialize(w)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    
+    return ret;
+}
+
+int SrsAacStreamEncoder::write_audio(int64_t timestamp, char* data, int size)
+{
+    return enc->write_audio(timestamp, data, size);
+}
+
+int SrsAacStreamEncoder::write_video(int64_t timestamp, char* data, int size)
+{
+    return enc->write_video(timestamp, data, size);
+}
+
+int SrsAacStreamEncoder::write_metadata(int64_t timestamp, char* data, int size)
+{
+    return enc->write_metadata(timestamp, data, size);
+}
+
+SrsStreamWriter::SrsStreamWriter(ISrsGoHttpResponseWriter* w)
 {
 {
     writer = w;
     writer = w;
 }
 }
 
 
-SrsFlvStreamWriter::~SrsFlvStreamWriter()
+SrsStreamWriter::~SrsStreamWriter()
 {
 {
 }
 }
 
 
-int SrsFlvStreamWriter::open(std::string /*file*/)
+int SrsStreamWriter::open(std::string /*file*/)
 {
 {
     return ERROR_SUCCESS;
     return ERROR_SUCCESS;
 }
 }
 
 
-void SrsFlvStreamWriter::close()
+void SrsStreamWriter::close()
 {
 {
 }
 }
 
 
-bool SrsFlvStreamWriter::is_open()
+bool SrsStreamWriter::is_open()
 {
 {
     return true;
     return true;
 }
 }
 
 
-int64_t SrsFlvStreamWriter::tellg()
+int64_t SrsStreamWriter::tellg()
 {
 {
     return 0;
     return 0;
 }
 }
 
 
-int SrsFlvStreamWriter::write(void* buf, size_t count, ssize_t* pnwrite)
+int SrsStreamWriter::write(void* buf, size_t count, ssize_t* pnwrite)
 {
 {
     if (pnwrite) {
     if (pnwrite) {
         *pnwrite = count;
         *pnwrite = count;
@@ -189,6 +275,20 @@ int SrsLiveStream::serve_http(ISrsGoHttpResponseWriter* w, SrsHttpMessage* r)
 {
 {
     int ret = ERROR_SUCCESS;
     int ret = ERROR_SUCCESS;
     
     
+    bool serve_flv_streaming = false;
+    bool serve_aac_streaming = false;
+    
+    srs_assert(entry);
+    if (srs_string_ends_with(entry->pattern, ".flv")) {
+        serve_flv_streaming = true;
+    } else if (srs_string_ends_with(entry->pattern, ".aac")) {
+        serve_aac_streaming = true;
+    } else {
+        ret = ERROR_HTTP_LIVE_STREAM_EXT;
+        srs_error("http: unsupported pattern %s", entry->pattern.c_str());
+        return ret;
+    }
+    
     // create consumer of souce.
     // create consumer of souce.
     SrsConsumer* consumer = NULL;
     SrsConsumer* consumer = NULL;
     if ((ret = source->create_consumer(consumer)) != ERROR_SUCCESS) {
     if ((ret = source->create_consumer(consumer)) != ERROR_SUCCESS) {
@@ -201,20 +301,25 @@ int SrsLiveStream::serve_http(ISrsGoHttpResponseWriter* w, SrsHttpMessage* r)
     SrsMessageArray msgs(SRS_PERF_MW_MSGS);
     SrsMessageArray msgs(SRS_PERF_MW_MSGS);
     // TODO: FIMXE: add pithy print.
     // TODO: FIMXE: add pithy print.
 
 
-    // write http header for ts.
+    // write http header for streaming.
     w->header()->set_content_length((int64_t)2 * 1024 * 1024 * 1024);
     w->header()->set_content_length((int64_t)2 * 1024 * 1024 * 1024);
-    w->header()->set_content_type("video/x-flv");
+    if (serve_flv_streaming) {
+        w->header()->set_content_type("video/x-flv");
+    }
+    if (serve_aac_streaming) {
+        w->header()->set_content_type("audio/x-aac");
+    }
     
     
     // the memory writer.
     // the memory writer.
-    SrsFlvStreamWriter writer(w);
+    SrsStreamWriter writer(w);
     
     
-    SrsFlvEncoder enc;
-    if ((ret = enc.initialize(&writer)) != ERROR_SUCCESS) {
-        return ret;
+    ISrsStreamEncoder* enc = NULL;
+    if (serve_flv_streaming) {
+        enc = new SrsFlvStreamEncoder();
     }
     }
+    SrsAutoFree(ISrsStreamEncoder, enc);
     
     
-    // write flv header.
-    if ((ret = enc.write_header())  != ERROR_SUCCESS) {
+    if ((ret = enc->initialize(&writer)) != ERROR_SUCCESS) {
         return ret;
         return ret;
     }
     }
     
     
@@ -223,23 +328,23 @@ int SrsLiveStream::serve_http(ISrsGoHttpResponseWriter* w, SrsHttpMessage* r)
         // each msg in msgs.msgs must be free, for the SrsMessageArray never free them.
         // each msg in msgs.msgs must be free, for the SrsMessageArray never free them.
         int count = 0;
         int count = 0;
         if ((ret = consumer->dump_packets(&msgs, count)) != ERROR_SUCCESS) {
         if ((ret = consumer->dump_packets(&msgs, count)) != ERROR_SUCCESS) {
-            srs_error("get messages from consumer failed. ret=%d", ret);
+            srs_error("http: get messages from consumer failed. ret=%d", ret);
             return ret;
             return ret;
         }
         }
         
         
         if (count <= 0) {
         if (count <= 0) {
-            srs_info("mw sleep %dms for no msg", mw_sleep);
+            srs_info("http: mw sleep %dms for no msg", mw_sleep);
             // directly use sleep, donot use consumer wait.
             // directly use sleep, donot use consumer wait.
             st_usleep(SRS_CONSTS_RTMP_PULSE_TIMEOUT_US);
             st_usleep(SRS_CONSTS_RTMP_PULSE_TIMEOUT_US);
             
             
             // ignore when nothing got.
             // ignore when nothing got.
             continue;
             continue;
         }
         }
-        srs_info("got %d msgs, min=%d, mw=%d", count, 
+        srs_info("http: got %d msgs, min=%d, mw=%d", count, 
             SRS_PERF_MW_MIN_MSGS, SRS_CONSTS_RTMP_PULSE_TIMEOUT_US / 1000);
             SRS_PERF_MW_MIN_MSGS, SRS_CONSTS_RTMP_PULSE_TIMEOUT_US / 1000);
         
         
         // sendout all messages.
         // sendout all messages.
-        ret = send_messages(&enc, msgs.msgs, count);
+        ret = streaming_send_messages(enc, msgs.msgs, count);
     
     
         // free the messages.
         // free the messages.
         for (int i = 0; i < count; i++) {
         for (int i = 0; i < count; i++) {
@@ -250,7 +355,7 @@ int SrsLiveStream::serve_http(ISrsGoHttpResponseWriter* w, SrsHttpMessage* r)
         // check send error code.
         // check send error code.
         if (ret != ERROR_SUCCESS) {
         if (ret != ERROR_SUCCESS) {
             if (!srs_is_client_gracefully_close(ret)) {
             if (!srs_is_client_gracefully_close(ret)) {
-                srs_error("send messages to client failed. ret=%d", ret);
+                srs_error("http: send messages to client failed. ret=%d", ret);
             }
             }
             return ret;
             return ret;
         }
         }
@@ -259,7 +364,7 @@ int SrsLiveStream::serve_http(ISrsGoHttpResponseWriter* w, SrsHttpMessage* r)
     return ret;
     return ret;
 }
 }
 
 
-int SrsLiveStream::send_messages(SrsFlvEncoder* enc, SrsSharedPtrMessage** msgs, int nb_msgs)
+int SrsLiveStream::streaming_send_messages(ISrsStreamEncoder* enc, SrsSharedPtrMessage** msgs, int nb_msgs)
 {
 {
     int ret = ERROR_SUCCESS;
     int ret = ERROR_SUCCESS;
     
     

@@ -41,6 +41,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 class SrsSource;
 class SrsSource;
 class SrsRequest;
 class SrsRequest;
 class SrsStSocket;
 class SrsStSocket;
+class SrsAacEncoder;
 class SrsFlvEncoder;
 class SrsFlvEncoder;
 class SrsHttpParser;
 class SrsHttpParser;
 class SrsHttpMessage;
 class SrsHttpMessage;
@@ -63,15 +64,64 @@ protected:
 };
 };
 
 
 /**
 /**
+* the stream encoder in some codec, for example, flv or aac.
+*/
+class ISrsStreamEncoder
+{
+public:
+    ISrsStreamEncoder();
+    virtual ~ISrsStreamEncoder();
+public:
+    virtual int initialize(SrsFileWriter* w) = 0;
+    virtual int write_audio(int64_t timestamp, char* data, int size) = 0;
+    virtual int write_video(int64_t timestamp, char* data, int size) = 0;
+    virtual int write_metadata(int64_t timestamp, char* data, int size) = 0;
+};
+
+/**
+* the flv stream encoder, remux rtmp stream to flv stream.
+*/
+class SrsFlvStreamEncoder : public ISrsStreamEncoder
+{
+private:
+    SrsFlvEncoder* enc;
+public:
+    SrsFlvStreamEncoder();
+    virtual ~SrsFlvStreamEncoder();
+public:
+    virtual int initialize(SrsFileWriter* w);
+    virtual int write_audio(int64_t timestamp, char* data, int size);
+    virtual int write_video(int64_t timestamp, char* data, int size);
+    virtual int write_metadata(int64_t timestamp, char* data, int size);
+};
+
+/**
+* the aac stream encoder, remux rtmp stream to aac stream.
+*/
+class SrsAacStreamEncoder : public ISrsStreamEncoder
+{
+private:
+    SrsAacEncoder* enc;
+public:
+    SrsAacStreamEncoder();
+    virtual ~SrsAacStreamEncoder();
+public:
+    virtual int initialize(SrsFileWriter* w);
+    virtual int write_audio(int64_t timestamp, char* data, int size);
+    virtual int write_video(int64_t timestamp, char* data, int size);
+    virtual int write_metadata(int64_t timestamp, char* data, int size);
+};
+
+/**
 * write stream to http response direclty.
 * write stream to http response direclty.
 */
 */
-class SrsFlvStreamWriter : public SrsFileWriter
+class SrsStreamWriter : public SrsFileWriter
 {
 {
 private:
 private:
     ISrsGoHttpResponseWriter* writer;
     ISrsGoHttpResponseWriter* writer;
 public:
 public:
-    SrsFlvStreamWriter(ISrsGoHttpResponseWriter* w);
-    virtual ~SrsFlvStreamWriter();
+    SrsStreamWriter(ISrsGoHttpResponseWriter* w);
+    virtual ~SrsStreamWriter();
 public:
 public:
     virtual int open(std::string file);
     virtual int open(std::string file);
     virtual void close();
     virtual void close();
@@ -97,7 +147,7 @@ public:
 public:
 public:
     virtual int serve_http(ISrsGoHttpResponseWriter* w, SrsHttpMessage* r);
     virtual int serve_http(ISrsGoHttpResponseWriter* w, SrsHttpMessage* r);
 private:
 private:
-    virtual int send_messages(SrsFlvEncoder* enc, SrsSharedPtrMessage** msgs, int nb_msgs);
+    virtual int streaming_send_messages(ISrsStreamEncoder* enc, SrsSharedPtrMessage** msgs, int nb_msgs);
 };
 };
 
 
 /**
 /**

+/*
+The MIT License (MIT)
+
+Copyright (c) 2013-2015 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.
+*/
+
+#include <srs_kernel_aac.hpp>
+
+// for srs-librtmp, @see https://github.com/winlinvip/simple-rtmp-server/issues/213
+#ifndef _WIN32
+#include <unistd.h>
+#endif
+
+#include <fcntl.h>
+#include <sstream>
+using namespace std;
+
+#include <srs_kernel_log.hpp>
+#include <srs_kernel_error.hpp>
+#include <srs_kernel_stream.hpp>
+#include <srs_kernel_file.hpp>
+
+#define SRS_FLV_TAG_HEADER_SIZE 11
+#define SRS_FLV_PREVIOUS_TAG_SIZE 4
+
+SrsAacEncoder::SrsAacEncoder()
+{
+    _fs = NULL;
+    tag_stream = new SrsStream();
+}
+
+SrsAacEncoder::~SrsAacEncoder()
+{
+    srs_freep(tag_stream);
+}
+
+int SrsAacEncoder::initialize(SrsFileWriter* fs)
+{
+    int ret = ERROR_SUCCESS;
+    
+    srs_assert(fs);
+    
+    if (!fs->is_open()) {
+        ret = ERROR_KERNEL_FLV_STREAM_CLOSED;
+        srs_warn("stream is not open for decoder. ret=%d", ret);
+        return ret;
+    }
+    
+    _fs = fs;
+    
+    return ret;
+}
+
+int SrsAacEncoder::write_header()
+{
+    int ret = ERROR_SUCCESS;
+    
+    // 9bytes header and 4bytes first previous-tag-size
+    static char flv_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
+    };
+    
+    // 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 SrsAacEncoder::write_header(char flv_header[9])
+{
+    int ret = ERROR_SUCCESS;
+    
+    // write data.
+    if ((ret = _fs->write(flv_header, 9, NULL)) != ERROR_SUCCESS) {
+        srs_error("write flv header failed. ret=%d", ret);
+        return ret;
+    }
+    
+    char pts[] = { (char)0x00, (char)0x00, (char)0x00, (char)0x00 };
+    if ((ret = _fs->write(pts, 4, NULL)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    
+    return ret;
+}
+
+int SrsAacEncoder::write_metadata(char type, char* data, int size)
+{
+    int ret = ERROR_SUCCESS;
+    
+    srs_assert(data);
+    
+    // 11 bytes tag header
+    static char tag_header[] = {
+        (char)type, // TagType UB [5], 18 = script data
+        (char)0x00, (char)0x00, (char)0x00, // DataSize UI24 Length of the message.
+        (char)0x00, (char)0x00, (char)0x00, // Timestamp UI24 Time in milliseconds at which the data in this tag applies.
+        (char)0x00, // TimestampExtended UI8
+        (char)0x00, (char)0x00, (char)0x00, // StreamID UI24 Always 0.
+    };
+    
+    // write data size.
+    if ((ret = tag_stream->initialize(tag_header + 1, 3)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    tag_stream->write_3bytes(size);
+    
+    if ((ret = write_tag(tag_header, sizeof(tag_header), data, size)) != ERROR_SUCCESS) {
+        srs_error("write flv data tag failed. ret=%d", ret);
+        return ret;
+    }
+    
+    return ret;
+}
+
+int SrsAacEncoder::write_audio(int64_t timestamp, char* data, int size)
+{
+    int ret = ERROR_SUCCESS;
+    
+    srs_assert(data);
+    
+    timestamp &= 0x7fffffff;
+    
+    // 11bytes tag header
+    static char tag_header[] = {
+        (char)8, // TagType UB [5], 8 = audio
+        (char)0x00, (char)0x00, (char)0x00, // DataSize UI24 Length of the message.
+        (char)0x00, (char)0x00, (char)0x00, // Timestamp UI24 Time in milliseconds at which the data in this tag applies.
+        (char)0x00, // TimestampExtended UI8
+        (char)0x00, (char)0x00, (char)0x00, // StreamID UI24 Always 0.
+    };
+    
+    // write data size.
+    if ((ret = tag_stream->initialize(tag_header + 1, 7)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    tag_stream->write_3bytes(size);
+    tag_stream->write_3bytes((int32_t)timestamp);
+    // default to little-endian
+    tag_stream->write_1bytes((timestamp >> 24) & 0xFF);
+    
+    if ((ret = write_tag(tag_header, sizeof(tag_header), data, size)) != ERROR_SUCCESS) {
+        srs_error("write flv audio tag failed. ret=%d", ret);
+        return ret;
+    }
+    
+    return ret;
+}
+
+int SrsAacEncoder::write_video(int64_t timestamp, char* data, int size)
+{
+    int ret = ERROR_SUCCESS;
+    
+    srs_assert(data);
+    
+    timestamp &= 0x7fffffff;
+    
+    // 11bytes tag header
+    static char tag_header[] = {
+        (char)9, // TagType UB [5], 9 = video
+        (char)0x00, (char)0x00, (char)0x00, // DataSize UI24 Length of the message.
+        (char)0x00, (char)0x00, (char)0x00, // Timestamp UI24 Time in milliseconds at which the data in this tag applies.
+        (char)0x00, // TimestampExtended UI8
+        (char)0x00, (char)0x00, (char)0x00, // StreamID UI24 Always 0.
+    };
+    
+    // write data size.
+    if ((ret = tag_stream->initialize(tag_header + 1, 7)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    tag_stream->write_3bytes(size);
+    tag_stream->write_3bytes((int32_t)timestamp);
+    // default to little-endian
+    tag_stream->write_1bytes((timestamp >> 24) & 0xFF);
+    
+    if ((ret = write_tag(tag_header, sizeof(tag_header), data, size)) != ERROR_SUCCESS) {
+        srs_error("write flv video tag failed. ret=%d", ret);
+        return ret;
+    }
+    
+    return ret;
+}
+
+int SrsAacEncoder::size_tag(int data_size)
+{
+    srs_assert(data_size >= 0);
+    return SRS_FLV_TAG_HEADER_SIZE + data_size + SRS_FLV_PREVIOUS_TAG_SIZE;
+}
+
+int SrsAacEncoder::write_tag(char* header, int header_size, char* tag, int tag_size)
+{
+    int ret = ERROR_SUCCESS;
+    
+    // write tag header.
+    if ((ret = _fs->write(header, header_size, NULL)) != ERROR_SUCCESS) {
+        srs_error("write flv tag header failed. ret=%d", ret);
+        return ret;
+    }
+    
+    // write tag data.
+    if ((ret = _fs->write(tag, tag_size, NULL)) != ERROR_SUCCESS) {
+        srs_error("write flv tag failed. ret=%d", ret);
+        return ret;
+    }
+    
+    // PreviousTagSizeN UI32 Size of last tag, including its header, in bytes.
+    static char pre_size[SRS_FLV_PREVIOUS_TAG_SIZE];
+    if ((ret = tag_stream->initialize(pre_size, SRS_FLV_PREVIOUS_TAG_SIZE)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    tag_stream->write_4bytes(tag_size + header_size);
+    if ((ret = _fs->write(pre_size, sizeof(pre_size), NULL)) != ERROR_SUCCESS) {
+        srs_error("write flv previous tag size failed. ret=%d", ret);
+        return ret;
+    }
+    
+    return ret;
+}
+
+

+/*
+The MIT License (MIT)
+
+Copyright (c) 2013-2015 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_KERNEL_AAC_HPP
+#define SRS_KERNEL_AAC_HPP
+
+/*
+#include <srs_kernel_aac.hpp>
+*/
+#include <srs_core.hpp>
+
+#include <string>
+
+class SrsStream;
+class SrsFileWriter;
+class SrsFileReader;
+
+/**
+* encode data to flv file.
+*/
+class SrsAacEncoder
+{
+private:
+    SrsFileWriter* _fs;
+private:
+    SrsStream* tag_stream;
+public:
+    SrsAacEncoder();
+    virtual ~SrsAacEncoder();
+public:
+    /**
+    * initialize the underlayer file stream.
+    * @remark user can initialize multiple times to encode multiple flv files.
+    * @remark, user must free the fs, flv encoder never close/free it.
+    */
+    virtual int initialize(SrsFileWriter* fs);
+public:
+    /**
+    * write flv header.
+    * write following:
+    *   1. E.2 The FLV header
+    *   2. PreviousTagSize0 UI32 Always 0
+    * that is, 9+4=13bytes.
+    */
+    virtual int write_header();
+    virtual int write_header(char flv_header[9]);
+    /**
+    * write flv metadata. 
+    * @param type, the type of data, or other message type.
+    * @param data, the amf0 metadata which serialize from:
+    *   AMF0 string: onMetaData,
+    *   AMF0 object: the metadata object.
+    * @remark assert data is not NULL.
+    */
+    virtual int write_metadata(char type, char* data, int size);
+    /**
+    * write audio/video packet.
+    * @remark assert data is not NULL.
+    */
+    virtual int write_audio(int64_t timestamp, char* data, int size);
+    virtual int write_video(int64_t timestamp, char* data, int size);
+public:
+    /**
+    * get the tag size,
+    * including the tag header, body, and 4bytes previous tag size.
+    * @remark assert data_size is not negative.
+    */
+    static int size_tag(int data_size);
+private:
+    virtual int write_tag(char* header, int header_size, char* tag, int tag_size);
+};
+
+#endif
+

@@ -211,6 +211,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #define ERROR_HTTP_PATTERN_DUPLICATED       4001
 #define ERROR_HTTP_PATTERN_DUPLICATED       4001
 #define ERROR_HTTP_URL_NOT_CLEAN            4002
 #define ERROR_HTTP_URL_NOT_CLEAN            4002
 #define ERROR_HTTP_CONTENT_LENGTH           4003
 #define ERROR_HTTP_CONTENT_LENGTH           4003
+#define ERROR_HTTP_LIVE_STREAM_EXT          4004
 
 
 /**
 /**
 * whether the error code is an system control error.
 * whether the error code is an system control error.

@@ -18,6 +18,8 @@ file
     ..\core\srs_core_performance.hpp,
     ..\core\srs_core_performance.hpp,
     ..\core\srs_core_performance.cpp,
     ..\core\srs_core_performance.cpp,
     kernel readonly separator,
     kernel readonly separator,
+    ..\kernel\srs_kernel_aac.hpp,
+    ..\kernel\srs_kernel_aac.cpp,
     ..\kernel\srs_kernel_codec.hpp,
     ..\kernel\srs_kernel_codec.hpp,
     ..\kernel\srs_kernel_codec.cpp,
     ..\kernel\srs_kernel_codec.cpp,
     ..\kernel\srs_kernel_consts.hpp,
     ..\kernel\srs_kernel_consts.hpp,