for #250, add comments for elemetary stream specifed by stream_id.

@@ -36,6 +36,8 @@ using namespace std;
 #include <srs_kernel_stream.hpp>
 #include <srs_kernel_ts.hpp>
 #include <srs_kernel_buffer.hpp>
+#include <srs_kernel_file.hpp>
+#include <srs_core_autofree.hpp>
 
 #ifdef SRS_AUTO_STREAM_CASTER
 
@@ -72,6 +74,39 @@ int SrsMpegtsOverUdp::on_udp_packet(sockaddr_in* from, char* buf, int nb_buf)
     // append to buffer.
     buffer->append(buf, nb_buf);
 
+    srs_info("udp: got %s:%d packet %d/%d bytes",
+        peer_ip.c_str(), peer_port, nb_buf, buffer->length());
+
+    // collect nMB data to parse in a time.
+    // TODO: FIXME: comment the following for release.
+    //if (buffer->length() < 3 * 1024 * 1024) return ret;
+    // TODO: FIXME: remove the debug to file.
+#if 0
+    SrsFileWriter fw;
+    if ((ret = fw.open("latest.ts")) != ERROR_SUCCESS) {
+        return ret;
+    }
+    if ((ret = fw.write(buffer->bytes(), buffer->length(), NULL)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    fw.close();
+#endif
+#if 0
+    SrsFileReader fr;
+    if ((ret = fr.open("latest.ts")) != ERROR_SUCCESS) {
+        return ret;
+    }
+    buffer->erase(buffer->length());
+    int nb_fbuf = fr.filesize();
+    char* fbuf = new char[nb_fbuf];
+    SrsAutoFree(char, fbuf);
+    if ((ret = fr.read(fbuf, nb_fbuf, NULL)) != ERROR_SUCCESS) {
+        return ret;
+    }
+    fr.close();
+    buffer->append(fbuf, nb_fbuf);
+#endif
+
     // find the sync byte of mpegts.
     char* p = buffer->bytes();
     for (int i = 0; i < buffer->length(); i++) {
@@ -87,12 +122,10 @@ int SrsMpegtsOverUdp::on_udp_packet(sockaddr_in* from, char* buf, int nb_buf)
 
     // drop ts packet when size not modulus by 188
     if (buffer->length() < SRS_TS_PACKET_SIZE) {
-        srs_info("udp: wait %s:%d packet %d/%d bytes",
+        srs_warn("udp: wait %s:%d packet %d/%d bytes",
             peer_ip.c_str(), peer_port, nb_buf, buffer->length());
         return ret;
     }
-    srs_info("udp: got %s:%d packet %d/%d bytes",
-        peer_ip.c_str(), peer_port, nb_buf, buffer->length());
 
     // use stream to parse ts packet.
     int nb_packet =  buffer->length() / SRS_TS_PACKET_SIZE;
@@ -122,6 +155,49 @@ int SrsMpegtsOverUdp::on_udp_packet(sockaddr_in* from, char* buf, int nb_buf)
 int SrsMpegtsOverUdp::on_ts_message(SrsTsMessage* msg)
 {
     int ret = ERROR_SUCCESS;
+
+    // about the bytes of msg, specified by elementary stream which indicates by PES_packet_data_byte and stream_id
+    // for example, when SrsTsStream of SrsTsChannel indicates stream_type is SrsTsStreamVideoMpeg4 and SrsTsStreamAudioMpeg4,
+    // the elementary stream can be mux in "2.11 Carriage of ISO/IEC 14496 data" in hls-mpeg-ts-iso13818-1.pdf, page 103
+    // @remark, the most popular stream_id is 0xe0 for h.264 over mpegts, which indicates the stream_id is video and 
+    //      stream_number is 0, where I guess the elementary is specified in 13818-2(video part).
+    //      because when audio stream_number is 0, the elementary is ADTS specified in 13818-7(aac part).
+
+    // about the bytes of PES_packet_data_byte, defined in hls-mpeg-ts-iso13818-1.pdf, page 58
+    // PES_packet_data_byte ¨C PES_packet_data_bytes shall be contiguous bytes of data from the elementary stream
+    // indicated by the packet¡¯s stream_id or PID. When the elementary stream data conforms to ITU-T
+    // Rec. H.262 | ISO/IEC 13818-2 or ISO/IEC 13818-3, the PES_packet_data_bytes shall be byte aligned to the bytes of this
+    // Recommendation | International Standard. The byte-order of the elementary stream shall be preserved. The number of
+    // PES_packet_data_bytes, N, is specified by the PES_packet_length field. N shall be equal to the value indicated in the
+    // PES_packet_length minus the number of bytes between the last byte of the PES_packet_length field and the first
+    // PES_packet_data_byte.
+    // 
+    // In the case of a private_stream_1, private_stream_2, ECM_stream, or EMM_stream, the contents of the
+    // PES_packet_data_byte field are user definable and will not be specified by ITU-T | ISO/IEC in the future.
+
+    // about the bytes of stream_id, define in  hls-mpeg-ts-iso13818-1.pdf, page 49
+    // stream_id ¨C In Program Streams, the stream_id specifies the type and number of the elementary stream as defined by the
+    // stream_id Table 2-18. In Transport Streams, the stream_id may be set to any valid value which correctly describes the
+    // elementary stream type as defined in Table 2-18. In Transport Streams, the elementary stream type is specified in the
+    // Program Specific Information as specified in 2.4.4.
+
+    // about the stream_id table, define in Table 2-18 ¨C Stream_id assignments, hls-mpeg-ts-iso13818-1.pdf, page 52.
+    // 
+    // 110x xxxx
+    // ISO/IEC 13818-3 or ISO/IEC 11172-3 or ISO/IEC 13818-7 or ISO/IEC
+    // 14496-3 audio stream number x xxxx
+    // ((sid >> 5) & 0x07) == SrsTsPESStreamIdAudio
+    // 
+    // 1110 xxxx
+    // ITU-T Rec. H.262 | ISO/IEC 13818-2 or ISO/IEC 11172-2 or ISO/IEC
+    // 14496-2 video stream number xxxx
+    // ((stream_id >> 4) & 0x0f) == SrsTsPESStreamIdVideo
+
+    srs_trace("mpegts: got %s dts=%"PRId64", pts=%"PRId64", size=%d, us=%d, cc=%d, sid=%#x(%s-%d)",
+        (msg->channel->apply == SrsTsPidApplyVideo)? "Video":"Audio", msg->dts, msg->pts, msg->payload->length(),
+        msg->packet->payload_unit_start_indicator, msg->continuity_counter, msg->sid,
+        msg->is_audio()? "A":msg->is_video()? "V":"N", msg->stream_number());
+
     // TODO: FIXME: implements it.
     return ret;
 }

@@ -421,6 +421,7 @@ SrsTsMessage::SrsTsMessage(SrsTsChannel* c, SrsTsPacket* p)
     packet = p;
 
     dts = pts = 0;
+    sid = (SrsTsPESStreamId)0x00;
     continuity_counter = 0;
     PES_packet_length = 0;
     payload = new SrsSimpleBuffer();
@@ -474,6 +475,26 @@ bool SrsTsMessage::fresh()
     return payload->length() == 0;
 }
 
+bool SrsTsMessage::is_audio()
+{
+    return ((sid >> 5) & 0x07) == SrsTsPESStreamIdAudio;
+}
+
+bool SrsTsMessage::is_video()
+{
+    return ((sid >> 4) & 0x0f) == SrsTsPESStreamIdVideo;
+}
+
+int SrsTsMessage::stream_number()
+{
+    if (is_audio()) {
+        return sid & 0x1f;
+    } else if (is_video()) {
+        return sid & 0x0f;
+    }
+    return -1;
+}
+
 ISrsTsHandler::ISrsTsHandler()
 {
 }
@@ -945,21 +966,22 @@ int SrsTsPayloadPES::decode(SrsStream* stream, SrsTsMessage** ppmsg)
     // should be 1 for the fresh msg.
     if (msg->fresh() && !packet->payload_unit_start_indicator) {
         ret = ERROR_STREAM_CASTER_TS_PSE;
-        srs_error("ts: PES fresh packet length=%d, unit_start=%d. ret=%d",
-            msg->PES_packet_length, packet->payload_unit_start_indicator, ret);
+        srs_error("ts: PES fresh packet length=%d, us=%d, cc=%d. ret=%d",
+            msg->PES_packet_length, packet->payload_unit_start_indicator, packet->continuity_counter,
+            ret);
         return ret;
     }
 
     // check when not fresh and PES_packet_length>0,
     // the payload_unit_start_indicator should never be 1 when not completed.
     if (!msg->fresh() && msg->PES_packet_length > 0
-        && packet->payload_unit_start_indicator
         && !msg->completed(packet->payload_unit_start_indicator)
+        && packet->payload_unit_start_indicator
     ) {
         ret = ERROR_STREAM_CASTER_TS_PSE;
-        srs_error("ts: PES packet length=%d, payload=%d, unit_start=%d. ret=%d",
-            msg->PES_packet_length, msg->payload->length(),
-            packet->payload_unit_start_indicator, ret);
+        srs_error("ts: PES packet length=%d, payload=%d, us=%d, cc=%d. ret=%d",
+            msg->PES_packet_length, msg->payload->length(), packet->payload_unit_start_indicator, 
+            packet->continuity_counter, ret);
 
         // reparse current msg.
         stream->skip(stream->pos() * -1);
@@ -975,7 +997,7 @@ int SrsTsPayloadPES::decode(SrsStream* stream, SrsTsMessage** ppmsg)
         if (msg->continuity_counter >= packet->continuity_counter
             && ((msg->continuity_counter + 1) & 0x0f) > packet->continuity_counter
         ) {
-            srs_warn("ts: drop PES %dB for duplicated continuity=%#x", msg->continuity_counter);
+            srs_warn("ts: drop PES %dB for duplicated cc=%#x", msg->continuity_counter);
             stream->skip(stream->size() - stream->pos());
             return ret;
         }
@@ -1037,8 +1059,10 @@ int SrsTsPayloadPES::decode(SrsStream* stream, SrsTsMessage** ppmsg)
         }
         int pos_packet = stream->pos();
 
-        // @remark SrsTsPESStreamIdAudio and SrsTsPESStreamIdVideo is not used here.
+        // @remark the sid indicates the elementary stream format.
+        //      the SrsTsPESStreamIdAudio and SrsTsPESStreamIdVideo is start by 0b110 or 0b1110
         SrsTsPESStreamId sid = (SrsTsPESStreamId)stream_id;
+        msg->sid = sid;
 
         if (sid != SrsTsPESStreamIdProgramStreamMap
             && sid != SrsTsPESStreamIdPaddingStream

@@ -162,6 +162,7 @@ enum SrsTsStream
     // ISO/IEC 14496-2 Visual
     SrsTsStreamVideoMpeg4      = 0x10,
     // ISO/IEC 14496-3 Audio with the LATM transport syntax as defined in ISO/IEC 14496-3 / AMD 1
+    SrsTsStreamAudioMpeg4      = 0x11,
     // ISO/IEC 14496-1 SL-packetized stream or FlexMux stream carried in PES packets
     // ISO/IEC 14496-1 SL-packetized stream or FlexMux stream carried in ISO/IEC14496_sections.
     // ISO/IEC 13818-6 Synchronized Download Protocol
@@ -189,18 +190,82 @@ struct SrsTsChannel
 };
 
 /**
+* the stream_id of PES payload of ts packet.
+* Table 2-18 – Stream_id assignments, hls-mpeg-ts-iso13818-1.pdf, page 52.
+*/
+enum SrsTsPESStreamId
+{
+    // program_stream_map
+    SrsTsPESStreamIdProgramStreamMap            = 0xbc, // 0b10111100
+    // private_stream_1
+    SrsTsPESStreamIdPrivateStream1              = 0xbd, // 0b10111101
+    // padding_stream
+    SrsTsPESStreamIdPaddingStream               = 0xbe, // 0b10111110
+    // private_stream_2
+    SrsTsPESStreamIdPrivateStream2              = 0xbf, // 0b10111111
+
+    // 110x xxxx
+    // ISO/IEC 13818-3 or ISO/IEC 11172-3 or ISO/IEC 13818-7 or ISO/IEC
+    // 14496-3 audio stream number x xxxx
+    // ((sid >> 5) & 0x07) == SrsTsPESStreamIdAudio
+    SrsTsPESStreamIdAudio                       = 0x06, // 0b110
+
+    // 1110 xxxx
+    // ITU-T Rec. H.262 | ISO/IEC 13818-2 or ISO/IEC 11172-2 or ISO/IEC
+    // 14496-2 video stream number xxxx
+    // ((stream_id >> 4) & 0x0f) == SrsTsPESStreamIdVideo
+    SrsTsPESStreamIdVideo                       = 0x0e, // 0b1110
+
+    // ECM_stream
+    SrsTsPESStreamIdEcmStream                   = 0xf0, // 0b11110000
+    // EMM_stream
+    SrsTsPESStreamIdEmmStream                   = 0xf1, // 0b11110001
+    // DSMCC_stream
+    SrsTsPESStreamIdDsmccStream                 = 0xf2, // 0b11110010
+    // 13522_stream
+    SrsTsPESStreamId13522Stream                 = 0xf3, // 0b11110011
+    // H_222_1_type_A
+    SrsTsPESStreamIdH2221TypeA                  = 0xf4, // 0b11110100
+    // H_222_1_type_B
+    SrsTsPESStreamIdH2221TypeB                  = 0xf5, // 0b11110101
+    // H_222_1_type_C
+    SrsTsPESStreamIdH2221TypeC                  = 0xf6, // 0b11110110
+    // H_222_1_type_D
+    SrsTsPESStreamIdH2221TypeD                  = 0xf7, // 0b11110111
+    // H_222_1_type_E
+    SrsTsPESStreamIdH2221TypeE                  = 0xf8, // 0b11111000
+    // ancillary_stream
+    SrsTsPESStreamIdAncillaryStream             = 0xf9, // 0b11111001
+    // SL_packetized_stream
+    SrsTsPESStreamIdSlPacketizedStream          = 0xfa, // 0b11111010
+    // FlexMux_stream
+    SrsTsPESStreamIdFlexMuxStream               = 0xfb, // 0b11111011
+    // reserved data stream
+    // 1111 1100 … 1111 1110
+    // program_stream_directory
+    SrsTsPESStreamIdProgramStreamDirectory      = 0xff, // 0b11111111
+};
+
+/**
 * the media audio/video message parsed from PES packet.
 */
 class SrsTsMessage
 {
-private:
+public:
     SrsTsChannel* channel;
     SrsTsPacket* packet;
 public:
+    // the timestamp in 90khz
     int64_t dts;
     int64_t pts;
+    // the id of pes stream to indicates the payload codec.
+    // @remark use is_audio() and is_video() to check it, and stream_number() to finger it out.
+    SrsTsPESStreamId sid;
+    // the size of payload, 0 indicates the length() of payload.
     u_int16_t PES_packet_length;
+    // the chunk id.
     u_int8_t continuity_counter;
+    // the payload bytes.
     SrsSimpleBuffer* payload;
 public:
     SrsTsMessage(SrsTsChannel* c, SrsTsPacket* p);
@@ -223,6 +288,20 @@ public:
     * whether the message is fresh.
     */
     virtual bool fresh();
+public:
+    /**
+    * whether the sid indicates the elementary stream audio.
+    */
+    virtual bool is_audio();
+    /**
+    * whether the sid indicates the elementary stream video.
+    */
+    virtual bool is_video();
+    /**
+    * when audio or video, get the stream number which specifies the format of stream.
+    * @return the stream number for audio/video; otherwise, -1.
+    */
+    virtual int stream_number();
 };
 
 /**
@@ -723,63 +802,6 @@ public:
 };
 
 /**
-* the stream_id of PES payload of ts packet.
-* Table 2-18 – Stream_id assignments, hls-mpeg-ts-iso13818-1.pdf, page 52.
-*/
-enum SrsTsPESStreamId
-{
-    // program_stream_map
-    SrsTsPESStreamIdProgramStreamMap            = 0xbc, // 0b10111100
-    // private_stream_1
-    SrsTsPESStreamIdPrivateStream1              = 0xbd, // 0b10111101
-    // padding_stream
-    SrsTsPESStreamIdPaddingStream               = 0xbe, // 0b10111110
-    // private_stream_2
-    SrsTsPESStreamIdPrivateStream2              = 0xbf, // 0b10111111
-
-    // 110x xxxx
-    // ISO/IEC 13818-3 or ISO/IEC 11172-3 or ISO/IEC 13818-7 or ISO/IEC
-    // 14496-3 audio stream number x xxxx
-    // (stream_id>>5)&0x07 == SrsTsPESStreamIdAudio
-    SrsTsPESStreamIdAudio                       = 0x06, // 0b110
-
-    // 1110 xxxx
-    // ITU-T Rec. H.262 | ISO/IEC 13818-2 or ISO/IEC 11172-2 or ISO/IEC
-    // 14496-2 video stream number xxxx
-    // (stream_id>>4)&0x0f == SrsTsPESStreamIdVideo
-    SrsTsPESStreamIdVideo                       = 0x0e, // 0b1110
-
-    // ECM_stream
-    SrsTsPESStreamIdEcmStream                   = 0xf0, // 0b11110000
-    // EMM_stream
-    SrsTsPESStreamIdEmmStream                   = 0xf1, // 0b11110001
-    // DSMCC_stream
-    SrsTsPESStreamIdDsmccStream                 = 0xf2, // 0b11110010
-    // 13522_stream
-    SrsTsPESStreamId13522Stream                 = 0xf3, // 0b11110011
-    // H_222_1_type_A
-    SrsTsPESStreamIdH2221TypeA                  = 0xf4, // 0b11110100
-    // H_222_1_type_B
-    SrsTsPESStreamIdH2221TypeB                  = 0xf5, // 0b11110101
-    // H_222_1_type_C
-    SrsTsPESStreamIdH2221TypeC                  = 0xf6, // 0b11110110
-    // H_222_1_type_D
-    SrsTsPESStreamIdH2221TypeD                  = 0xf7, // 0b11110111
-    // H_222_1_type_E
-    SrsTsPESStreamIdH2221TypeE                  = 0xf8, // 0b11111000
-    // ancillary_stream
-    SrsTsPESStreamIdAncillaryStream             = 0xf9, // 0b11111001
-    // SL_packetized_stream
-    SrsTsPESStreamIdSlPacketizedStream          = 0xfa, // 0b11111010
-    // FlexMux_stream
-    SrsTsPESStreamIdFlexMuxStream               = 0xfb, // 0b11111011
-    // reserved data stream
-    // 1111 1100 … 1111 1110
-    // program_stream_directory
-    SrsTsPESStreamIdProgramStreamDirectory      = 0xff, // 0b11111111
-};
-
-/**
 * the PES payload of ts packet.
 * 2.4.3.6 PES packet, hls-mpeg-ts-iso13818-1.pdf, page 49
 */