bool midi_file_write(const midi & m, const char * fn) {
ofstream out(fn, ios_base::out | ios_base::binary);
if (out.fail()) return false;
printHeader(m, out);
int lengths[m.trackCount()];
uint16_t ff = getFileFormat(m);
if (m.trackCount()) {
lengths[0] = writeTrack(m.tracks(0), out, m.getTicksPerQuaterNote(), true);
for (unsigned i = 1; i < m.trackCount(); ++i) {
if (ff < 2)
lengths[i] = writeTrack(m.tracks(i), out);
else
lengths[i] = writeTrack(m.tracks(i), out, m.getTicksPerQuaterNote(), true);
}
}
out.seekp(14, ios_base::beg);
for (unsigned i = 0; i < m.trackCount(); ++i) {
out.seekp(4, ios_base::cur);
printUint32_t(lengths[i] - 8, out);
out.seekp(lengths[i] - 8, ios_base::cur);
}
out.close();
return out.fail();
}
void printHeader(const midi& m, ostream &out) {
out.write("MThd\0\0\0\6", 8);
if (m.trackCount() == 0)
throw "No tracks! Cannot save a file.";
else if (m.trackCount() == 1)
printUint16_t(1, out);
else {
printUint16_t(getFileFormat(m), out);
}
printUint16_t(m.trackCount(), out);
printUint16_t((uint16_t) m.getTicksPerQuaterNote(), out);
}
uint16_t getFileFormat(const midi& m) {
if (m.trackCount() <= 1)
return 0;
uint16_t ff = 1;
for (unsigned i = 1; i < m.trackCount(); ++i) {
if (m.tracks(i).getTrackTempo() != m.tracks(0).getTrackTempo()) {
ff = 2;
break;
}
}
return ff;
}
void align_midi_events(midi & m, const tracktempo & newtempo) {
for (unsigned int i = 0; i < m.trackCount(); i++) {
tracktempo oldtempo = m.tracks(i).getTrackTempo();
for (unsigned int j = 0; j < m.tracks(i).eventCount(); j++) {
align_midi_event(m.tracks(i), j, newtempo);
m.tracks(i).setTrackTempo(newtempo);
}
}
}
