diff options
author | Robin Gareus <robin@gareus.org> | 2020-05-12 00:05:42 +0200 |
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committer | Robin Gareus <robin@gareus.org> | 2020-05-12 01:49:41 +0200 |
commit | 7c15ad099f759f2bfdb2701b96fb5335e916a15b (patch) | |
tree | 57e9e0684c0f984af4d70e6b643dd637f4ad7a9c /libs/backends/dummy/dummy_audiobackend.cc | |
parent | 20c09ccfc338b59ed321bc7429efa0faa22e067c (diff) |
Dummy Backend: add a MTC generator
Diffstat (limited to 'libs/backends/dummy/dummy_audiobackend.cc')
-rw-r--r-- | libs/backends/dummy/dummy_audiobackend.cc | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/libs/backends/dummy/dummy_audiobackend.cc b/libs/backends/dummy/dummy_audiobackend.cc index ca9a93e583..b42f29df84 100644 --- a/libs/backends/dummy/dummy_audiobackend.cc +++ b/libs/backends/dummy/dummy_audiobackend.cc @@ -896,6 +896,7 @@ DummyAudioBackend::get_latency_range (PortEngine::PortHandle port_handle, bool f } r = port->latency_range (for_playback); +#ifndef ZERO_LATENCY if (port->is_physical() && port->is_terminal()) { if (port->is_input() && for_playback) { const size_t l_in = _samples_per_period * .25; @@ -910,6 +911,7 @@ DummyAudioBackend::get_latency_range (PortEngine::PortHandle port_handle, bool f r.max += l_out; } } +#endif return r; } @@ -1695,6 +1697,10 @@ DummyMidiPort::setup_generator (int seq_id, const float sr) _midi_seq_spb = sr * .5f; // 120 BPM, beat_time 1.0 per beat. _midi_seq_pos = 0; _midi_seq_time = 0; + + if (_midi_seq_dat && _midi_seq_dat[0].beat_time < 0) { + _midi_seq_spb = sr / 25; // 25fps MTC + } return DummyMidiData::sequence_names[seq_id]; } @@ -1728,6 +1734,50 @@ void DummyMidiPort::midi_generate (const pframes_t n_samples) return; } + if (_midi_seq_dat[0].beat_time < 0) { + /* MTC generator */ + const int audio_samples_per_video_frame = _midi_seq_spb; // sample-rate / 25 + const int audio_samples_per_qf = audio_samples_per_video_frame / 4; + + samplepos_t tc_frame = _midi_seq_time / audio_samples_per_video_frame; + samplepos_t tc_sample = tc_frame * audio_samples_per_video_frame; + int qf = (tc_frame & 1) ? 4 : 0; + while (tc_sample < _midi_seq_time + n_samples) { + if (tc_sample >= _midi_seq_time) { + uint8_t buf[2]; + buf[0] = 0xf1; + + int frame = tc_frame % 25; + int second = (tc_frame / 25) % 60; + int minute = ((tc_frame / 25) / 60) % 60; + int hour = (((tc_frame / 25) / 60) / 60); + + switch(qf & 7) { + case 0: buf[1] = 0x00 | (frame & 0x0f); break; + case 1: buf[1] = 0x10 | ((frame & 0xf0) >> 4); break; + case 2: buf[1] = 0x20 | (second & 0x0f); break; + case 3: buf[1] = 0x30 | ((second & 0xf0) >> 4); break; + case 4: buf[1] = 0x40 | (minute & 0x0f); break; + case 5: buf[1] = 0x50 | ((minute & 0xf0) >> 4); break; + case 6: buf[1] = 0x60 | ((/* 25fps*/ 0x20 | hour) & 0x0f); break; + case 7: buf[1] = 0x70 | (((/* 25fps*/ 0x20 | hour) & 0xf0)>>4); break; + } + _buffer.push_back (boost::shared_ptr<DummyMidiEvent>(new DummyMidiEvent (tc_sample - _midi_seq_time, buf, 2))); + } + tc_sample += audio_samples_per_qf; + if (++qf == 8) { + ++tc_frame; + qf = 0; + } + } + + _midi_seq_time += n_samples; + if (_midi_seq_time >= /* 24 * 3600 * 25 */ 2160000LL * audio_samples_per_video_frame) { + _midi_seq_time -= 2160000LL * audio_samples_per_video_frame; // 24h @ 25fps + } + return; + } + while (1) { const int32_t ev_beat_time = _midi_seq_dat[_midi_seq_pos].beat_time * _midi_seq_spb - _midi_seq_time; if (ev_beat_time < 0) { |