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refs #144 , improved SELCAL in a way that SELCAL tones will always end with 0 amplitude.

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* method to write values in buffer -> writeAmplitudeToBuffer
* fixes the range from the last 0 pass so SELCAL tones will always end with 0 amplitude
This commit is contained in:
Klaus Basan
2014-02-26 02:27:31 +01:00
parent 59ff750b4a
commit a43621774b
2 changed files with 70 additions and 30 deletions
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94
src/blacksound/soundgenerator.cpp
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@@ -157,14 +157,14 @@ namespace BlackSound
foreach(Tone t, this->m_tones)
{
qint64 bytesPerTone = this->m_audioFormat.sampleRate() * bytesForAllChannels * t.m_durationMs / 1000;
qint64 last0AmplitudeSample = bytesPerTone; // last sample when amplitude was 0
int sampleIndexPerTone = 0;
while (bytesPerTone)
{
// http://hyperphysics.phy-astr.gsu.edu/hbase/audio/sumdif.html
// http://math.stackexchange.com/questions/164369/how-do-you-calculate-the-frequency-perceived-by-humans-of-two-sinusoidal-waves-a
const double pseudoTime = double(sampleIndexPerTone % this->m_audioFormat.sampleRate()) / this->m_audioFormat.sampleRate();
double amplitude = 0; // silence
double amplitude = 0.0; // amplitude -1 -> +1 , 0 is silence
if (t.m_frequencyHz > 10)
{
// the combination of two frequencies actually would have 2*amplitude,
@@ -176,40 +176,75 @@ namespace BlackSound
qCos(M_PI * (t.m_frequencyHz - t.m_secondaryFrequencyHz) * pseudoTime);
}
// avoid overflow
Q_ASSERT(amplitude <= 1.0 && amplitude >= -1.0);
if (amplitude < -1.0)
amplitude = -1.0;
else if (amplitude > 1.0)
amplitude = 1.0;
else if (qAbs(amplitude) < double(1.0 / 65535))
{
amplitude = 0;
last0AmplitudeSample = bytesPerTone;
}
// generate this for all channels, usually 1 channel
for (int i = 0; i < this->m_audioFormat.channelCount(); ++i)
{
if (this->m_audioFormat.sampleSize() == 8 && this->m_audioFormat.sampleType() == QAudioFormat::UnSignedInt)
{
const quint8 value = static_cast<quint8>((1.0 + amplitude) / 2 * 255);
*reinterpret_cast<quint8 *>(bufferPointer) = value;
}
else if (this->m_audioFormat.sampleSize() == 8 && this->m_audioFormat.sampleType() == QAudioFormat::SignedInt)
{
const qint8 value = static_cast<qint8>(amplitude * 127);
*reinterpret_cast<quint8 *>(bufferPointer) = value;
}
else if (this->m_audioFormat.sampleSize() == 16 && this->m_audioFormat.sampleType() == QAudioFormat::UnSignedInt)
{
quint16 value = static_cast<quint16>((1.0 + amplitude) / 2 * 65535);
if (this->m_audioFormat.byteOrder() == QAudioFormat::LittleEndian)
qToLittleEndian<quint16>(value, bufferPointer);
else
qToBigEndian<quint16>(value, bufferPointer);
}
else if (this->m_audioFormat.sampleSize() == 16 && this->m_audioFormat.sampleType() == QAudioFormat::SignedInt)
{
qint16 value = static_cast<qint16>(amplitude * 32767);
if (this->m_audioFormat.byteOrder() == QAudioFormat::LittleEndian)
qToLittleEndian<qint16>(value, bufferPointer);
else
qToBigEndian<qint16>(value, bufferPointer);
}
this->writeAmplitudeToBuffer(amplitude, bufferPointer);
bufferPointer += bytesPerSample;
bytesPerTone -= bytesPerSample;
}
++sampleIndexPerTone;
}
// fixes the range from the last 0 pass through
if (last0AmplitudeSample > 0)
{
bufferPointer -= last0AmplitudeSample;
while (last0AmplitudeSample)
{
double amplitude = 0.0; // amplitude -1 -> +1 , 0 is silence
// generate this for all channels, usually 1 channel
for (int i = 0; i < this->m_audioFormat.channelCount(); ++i)
{
this->writeAmplitudeToBuffer(amplitude, bufferPointer);
bufferPointer += bytesPerSample;
last0AmplitudeSample -= bytesPerSample;
}
}
}
}
}
void CSoundGenerator::writeAmplitudeToBuffer(const double amplitude, unsigned char *bufferPointer)
{
if (this->m_audioFormat.sampleSize() == 8 && this->m_audioFormat.sampleType() == QAudioFormat::UnSignedInt)
{
const quint8 value = static_cast<quint8>((1.0 + amplitude) / 2 * 255);
*reinterpret_cast<quint8 *>(bufferPointer) = value;
}
else if (this->m_audioFormat.sampleSize() == 8 && this->m_audioFormat.sampleType() == QAudioFormat::SignedInt)
{
const qint8 value = static_cast<qint8>(amplitude * 127);
*reinterpret_cast<quint8 *>(bufferPointer) = value;
}
else if (this->m_audioFormat.sampleSize() == 16 && this->m_audioFormat.sampleType() == QAudioFormat::UnSignedInt)
{
quint16 value = static_cast<quint16>((1.0 + amplitude) / 2 * 65535);
if (this->m_audioFormat.byteOrder() == QAudioFormat::LittleEndian)
qToLittleEndian<quint16>(value, bufferPointer);
else
qToBigEndian<quint16>(value, bufferPointer);
}
else if (this->m_audioFormat.sampleSize() == 16 && this->m_audioFormat.sampleType() == QAudioFormat::SignedInt)
{
qint16 value = static_cast<qint16>(amplitude * 32767);
if (this->m_audioFormat.byteOrder() == QAudioFormat::LittleEndian)
qToLittleEndian<qint16>(value, bufferPointer);
else
qToBigEndian<qint16>(value, bufferPointer);
}
}
@@ -450,7 +485,6 @@ namespace BlackSound
void CSoundGenerator::playFile(qint32 volume, const QString &file, bool removeFileAfterPlaying)
{
if (!QFile::exists(file)) return;
QMediaPlayer *mediaPlayer = CSoundGenerator::mediaPlayer();
QMediaResource mediaResource(QUrl(file), "audio");
QMediaContent media(mediaResource);