M17 mod audio with file input

2026-06-04 06:54:39 -04:00 · 2022-06-29 08:45:44 +02:00
parent 1fc688c904
commit 8f48d7d135
13 changed files with 713 additions and 27 deletions
@@ -15,21 +15,36 @@
 // along with this program. If not, see <http://www.gnu.org/licenses/>.          //
 ///////////////////////////////////////////////////////////////////////////////////

+#include <codec2/codec2.h>
+
 #include "m17/M17Modulator.h"

 #include "m17modprocessor.h"

 MESSAGE_CLASS_DEFINITION(M17ModProcessor::MsgSendSMS, Message)
+MESSAGE_CLASS_DEFINITION(M17ModProcessor::MsgSendAudio, Message)
+MESSAGE_CLASS_DEFINITION(M17ModProcessor::MsgSendAudioFrame, Message)
+MESSAGE_CLASS_DEFINITION(M17ModProcessor::MsgStartAudio, Message)
+MESSAGE_CLASS_DEFINITION(M17ModProcessor::MsgStopAudio, Message)

 M17ModProcessor::M17ModProcessor() :
-    m_m17Modulator("MYCALL", "")
+    m_m17Modulator("MYCALL", ""),
+    m_lichSegmentIndex(0),
+    m_audioFrameIndex(0),
+    m_audioFrameNumber(0)
 {
    m_basebandFifo.setSize(96000);
+    m_basebandFifoLow = 4096;
+    m_basebandFifoHigh = 96000 - m_basebandFifoLow;
+    m_decimator.initialize(8000.0, 3000.0, 6);
+    m_codec2 = ::codec2_create(CODEC2_MODE_3200);
    connect(&m_inputMessageQueue, SIGNAL(messageEnqueued()), this, SLOT(handleInputMessages()));
 }

 M17ModProcessor::~M17ModProcessor()
-{}
+{
+    codec2_destroy(m_codec2);
+}

 bool M17ModProcessor::handleMessage(const Message& cmd)
 {
@@ -43,6 +58,34 @@ bool M17ModProcessor::handleMessage(const Message& cmd)
        // test(notif.getSourceCall(), notif.getDestCall());
        return true;
    }
+    else if (MsgSendAudio::match(cmd))
+    {
+        MsgSendAudio& notif = (MsgSendAudio&) cmd;
+        // qDebug("M17ModProcessor::handleMessage: MsgSendAudio: %lu samples", notif.getAudioBuffer().size());
+        processAudio(notif.getAudioBuffer());
+        return true;
+    }
+    else if (MsgSendAudioFrame::match(cmd))
+    {
+        MsgSendAudioFrame& notif = (MsgSendAudioFrame&) cmd;
+        m_audioFrame = notif.getAudioFrame();
+        processAudioFrame();
+        return true;
+    }
+    else if (MsgStartAudio::match(cmd))
+    {
+        MsgStartAudio& notif = (MsgStartAudio&) cmd;
+        qDebug("M17ModProcessor::handleMessage: MsgStartAudio: %s to %s",
+            qPrintable(notif.getSourceCall()), qPrintable(notif.getDestCall()));
+        audioStart(notif.getSourceCall(), notif.getDestCall());
+        return true;
+    }
+    else if (MsgStopAudio::match(cmd))
+    {
+        qDebug("M17ModProcessor::handleMessage: MsgStopAudio");
+        audioStop();
+        return true;
+    }

    return false;
 }
@@ -107,6 +150,43 @@ void M17ModProcessor::processPacket(const QString& sourceCall, const QString& de
    send_eot(); // EOT
 }

+void M17ModProcessor::audioStart(const QString& sourceCall, const QString& destCall)
+{
+    qDebug("M17ModProcessor::audioStart");
+    m_m17Modulator.source(sourceCall.toStdString());
+    m_m17Modulator.dest(destCall.toStdString());
+    m_audioFrameNumber = 0;
+
+    send_preamble(); // preamble
+
+    // LSF
+    std::array<uint8_t, 30> lsf;
+    std::array<int8_t, 368> lsf_frame = mobilinkd::M17Modulator::make_lsf(lsf, sourceCall.toStdString(), destCall.toStdString());
+    output_baseband(mobilinkd::M17Modulator::LSF_SYNC_WORD, lsf_frame);
+
+    // Prepare LICH
+    for (size_t i = 0; i < m_lich.size(); ++i)
+    {
+        std::array<uint8_t, 5> segment;
+        std::copy(lsf.begin() + i*5, lsf.begin() + (i + 1)*5, segment.begin());
+        mobilinkd::M17Modulator::lich_segment_t lich_segment = mobilinkd::M17Modulator::make_lich_segment(segment, i);
+        std::copy(lich_segment.begin(), lich_segment.end(), m_lich[i].begin());
+    }
+}
+
+void M17ModProcessor::audioStop()
+{
+    qDebug("M17ModProcessor::audioStop");
+    if (m_audioFrameIndex > 0) // send remainder audio + null samples
+    {
+        std::fill(m_audioFrame.begin() + m_audioFrameIndex, m_audioFrame.end(), 0);
+        processAudioFrame();
+        m_audioFrameIndex = 0;
+    }
+
+    send_eot(); // EOT
+}
+
 void M17ModProcessor::send_preamble()
 {
    // Preamble is simple... bytes -> symbols -> baseband.
@@ -117,6 +197,80 @@ void M17ModProcessor::send_preamble()
    m_basebandFifo.write(preamble_baseband.data(), 1920);
 }

+void M17ModProcessor::processAudio(const std::vector<int16_t>& audioBuffer)
+{
+    int audioBufferRemainder = audioBuffer.size();
+    std::vector<int16_t>::const_iterator audioBufferIt = audioBuffer.begin();
+    int audioFrameRemainder = m_audioFrame.size() - m_audioFrameIndex;
+
+    if (audioBufferRemainder < audioFrameRemainder) {
+        qDebug("M17ModProcessor::processAudio: too few samples: %d/%d", audioBufferRemainder, audioFrameRemainder);
+    }
+
+    while (audioBufferRemainder >= (int) m_audioFrame.size())
+    {
+        m_audioFrame.fill(0);
+
+        std::copy(
+            audioBufferIt,
+            audioBufferIt + audioFrameRemainder,
+            m_audioFrame.begin() + m_audioFrameIndex);
+
+        if (m_basebandFifo.getFill() < m_basebandFifoHigh) {
+            processAudioFrame();
+        }
+
+        if (m_basebandFifo.getFill() < m_basebandFifoLow)
+        {
+            qDebug("M17ModProcessor::processAudio: repeat frame: %d", m_basebandFifo.getFill());
+            // m_audioFrame.fill(0);
+            processAudioFrame();
+        }
+
+        audioBufferRemainder -= audioFrameRemainder;
+        audioBufferIt += audioFrameRemainder;
+        m_audioFrameIndex = 0;
+        audioFrameRemainder = m_audioFrame.size();
+    }
+
+    std::copy(audioBufferIt, audioBuffer.end(), m_audioFrame.begin());
+    m_audioFrameIndex = audioBufferRemainder;
+}
+
+void M17ModProcessor::processAudioFrame()
+{
+    std::array<uint8_t, 16> audioPayload = encodeAudio(m_audioFrame);
+    std::array<int8_t, 272> audioDataBits = mobilinkd::M17Modulator::make_stream_data_frame(m_audioFrameNumber++, audioPayload);
+
+    if (m_audioFrameNumber == 0x8000) {
+        m_audioFrameNumber = 0;
+    }
+
+    std::array<uint8_t, 96>& lich = m_lich[m_lichSegmentIndex++];
+
+    if (m_lichSegmentIndex == 6) {
+        m_lichSegmentIndex = 0;
+    }
+
+    std::array<int8_t, 368> temp;
+    auto it = std::copy(lich.begin(), lich.end(), temp.begin());
+    std::copy(audioDataBits.begin(), audioDataBits.end(), it);
+    mobilinkd::M17Modulator::interleave_and_randomize(temp);
+
+    output_baseband(mobilinkd::M17Modulator::STREAM_SYNC_WORD, temp);
+}
+
+std::array<uint8_t, 16> M17ModProcessor::encodeAudio(std::array<int16_t, 320*6>& audioFrame)
+{
+    std::array<int16_t, 320> audioFrame8k;
+    m_decimator.decimate(audioFrame.data(), audioFrame8k.data(), 320);
+    std::array<uint8_t, 16> result;
+    // result.fill(0); // test
+    codec2_encode(m_codec2, &result[0], const_cast<int16_t*>(&audioFrame8k[0]));
+    codec2_encode(m_codec2, &result[8], const_cast<int16_t*>(&audioFrame8k[160]));
+    return result;
+}
+
 void M17ModProcessor::send_eot()
 {
    std::array<uint8_t, 2> EOT_SYNC = { 0x55, 0x5D };