EDI: add audio levels and program version TAGs

4 files changed, 114 insertions, 2 deletions

diff --git a/contrib/edi/TagItems.cpp b/contrib/edi/TagItems.cpp
index 35a6852..9746469 100644
--- a/contrib/edi/TagItems.cpp
+++ b/contrib/edi/TagItems.cpp
@@ -379,5 +379,71 @@ std::vector<uint8_t> TagStarDMY::Assemble()
     return packet;
 }
 
+TagODRVersion::TagODRVersion(const std::string& version, uint32_t uptime_s) :
+    m_version(version),
+    m_uptime(uptime_s)
+{
+}
+
+std::vector<uint8_t> TagODRVersion::Assemble()
+{
+    std::string pack_data("ODRv");
+    std::vector<uint8_t> packet(pack_data.begin(), pack_data.end());
+
+    const size_t length = m_version.size() + sizeof(uint32_t);
+
+    packet.resize(4 + 4 + length);
+
+    const uint32_t length_bits = length * 8;
+
+    size_t i = 4;
+    packet[i++] = (length_bits >> 24) & 0xFF;
+    packet[i++] = (length_bits >> 16) & 0xFF;
+    packet[i++] = (length_bits >> 8) & 0xFF;
+    packet[i++] = length_bits & 0xFF;
+
+    copy(m_version.cbegin(), m_version.cend(), packet.begin() + i);
+    i += m_version.size();
+
+    packet[i++] = (m_uptime >> 24) & 0xFF;
+    packet[i++] = (m_uptime >> 16) & 0xFF;
+    packet[i++] = (m_uptime >> 8) & 0xFF;
+    packet[i++] = m_uptime & 0xFF;
+
+    return packet;
+}
+
+TagODRAudioLevels::TagODRAudioLevels(int16_t audiolevel_left, int16_t audiolevel_right) :
+    m_audio_left(audiolevel_left),
+    m_audio_right(audiolevel_right)
+{
+}
+
+std::vector<uint8_t> TagODRAudioLevels::Assemble()
+{
+    std::string pack_data("ODRa");
+    std::vector<uint8_t> packet(pack_data.begin(), pack_data.end());
+
+    constexpr size_t length = 2*sizeof(int16_t);
+
+    packet.resize(4 + 4 + length);
+
+    const uint32_t length_bits = length * 8;
+
+    size_t i = 4;
+    packet[i++] = (length_bits >> 24) & 0xFF;
+    packet[i++] = (length_bits >> 16) & 0xFF;
+    packet[i++] = (length_bits >> 8) & 0xFF;
+    packet[i++] = length_bits & 0xFF;
+
+    packet[i++] = (m_audio_left >> 8) & 0xFF;
+    packet[i++] = m_audio_left & 0xFF;
+
+    packet[i++] = (m_audio_right >> 8) & 0xFF;
+    packet[i++] = m_audio_right & 0xFF;
+
+    return packet;
+}
+
 }
 
diff --git a/contrib/edi/TagItems.h b/contrib/edi/TagItems.h
index 25daa14..5c81b01 100644
--- a/contrib/edi/TagItems.h
+++ b/contrib/edi/TagItems.h
@@ -225,5 +225,29 @@ class TagStarDMY : public TagItem
         uint32_t length_;
 };
 
+// Custom TAG that carries version information of the EDI source
+class TagODRVersion : public TagItem
+{
+    public:
+        TagODRVersion(const std::string& version, uint32_t uptime_s);
+        std::vector<uint8_t> Assemble();
+
+    private:
+        std::string m_version;
+        uint32_t m_uptime;
+};
+
+// Custom TAG that carries audio level metadata
+class TagODRAudioLevels : public TagItem
+{
+    public:
+        TagODRAudioLevels(int16_t audiolevel_left, int16_t audiolevel_right);
+        std::vector<uint8_t> Assemble();
+
+    private:
+        int16_t m_audio_left;
+        int16_t m_audio_right;
+};
+
 }
 
diff --git a/src/Outputs.cpp b/src/Outputs.cpp
index eadbc5e..d0d3ca4 100644
--- a/src/Outputs.cpp
+++ b/src/Outputs.cpp
@@ -188,6 +188,7 @@ bool EDI::write_frame(const uint8_t *buf, size_t len)
         using Sec = chrono::seconds;
         const auto now = chrono::time_point_cast<Sec>(chrono::system_clock::now());
         m_edi_time = chrono::system_clock::to_time_t(now) + (m_delay_ms / 1000);
+        m_send_version_at_time = m_edi_time;
 
         /* TODO we still have to see if 24ms granularity is achievable, given that
          * one DAB+ super frame is carried over more than 1 ETI frame.
@@ -206,6 +207,8 @@ bool EDI::write_frame(const uint8_t *buf, size_t len)
     if (m_timestamp > 0xf9FFff) {
         m_timestamp -= 0xfa0000; // Substract 16384000, corresponding to one second
         m_edi_time += 1;
+
+        m_num_seconds_sent++;
     }
 
     m_edi_tagDSTI.set_edi_time(m_edi_time, m_clock_tai.get_offset());
@@ -214,13 +217,23 @@ bool EDI::write_frame(const uint8_t *buf, size_t len)
     m_edi_tagDSTI.rfadf = false;
     // DFCT is handled inside the TagDSTI
 
-    // TODO invent custom TAG to carry audio levels metadata
-
     edi::TagSSm edi_tagPayload;
     // TODO make edi_tagPayload.stid configurable
     edi_tagPayload.istd_data = buf;
     edi_tagPayload.istd_length = len;
 
+    edi::TagODRAudioLevels edi_tagAudioLevels(m_audio_left, m_audio_right);
+
+    stringstream ss;
+    ss << PACKAGE_NAME << " " <<
+#if defined(GITVERSION)
+        GITVERSION;
+#else
+    PACKAGE_VERSION;
+#endif
+    edi::TagODRVersion edi_tagVersion(ss.str(), m_num_seconds_sent);
+
+
     // The above Tag Items will be assembled into a TAG Packet
     edi::TagPacket edi_tagpacket(m_edi_conf.tagpacket_alignment);
 
@@ -228,6 +241,13 @@ bool EDI::write_frame(const uint8_t *buf, size_t len)
     edi_tagpacket.tag_items.push_back(&edi_tagStarPtr);
     edi_tagpacket.tag_items.push_back(&m_edi_tagDSTI);
     edi_tagpacket.tag_items.push_back(&edi_tagPayload);
+    edi_tagpacket.tag_items.push_back(&edi_tagAudioLevels);
+
+    // Send version information only every 10 seconds to save bandwidth
+    if (m_send_version_at_time < m_edi_time) {
+        m_send_version_at_time += 10;
+        edi_tagpacket.tag_items.push_back(&edi_tagVersion);
+    }
 
     m_edi_sender->write(edi_tagpacket);
 
diff --git a/src/Outputs.h b/src/Outputs.h
index 131f35c..0f1f34f 100644
--- a/src/Outputs.h
+++ b/src/Outputs.h
@@ -147,7 +147,9 @@ class EDI: public Base {
         std::shared_ptr<edi::Sender> m_edi_sender;
 
         uint32_t m_timestamp = 0;
+        uint32_t m_num_seconds_sent = 0;
         std::time_t m_edi_time = 0;
+        std::time_t m_send_version_at_time = 0;
 
         edi::TagDSTI m_edi_tagDSTI;