Initial version. Allows listing and measuring

Generator.cpp

@@ -0,0 +1,116 @@
+#include "Generator.h"
+#include <qendian.h>
+#include <qmath.h>
+
+
+Generator::Generator(const QAudioFormat &format
+    , qint64 durationUs
+    , int sampleRate, bool right)
+{
+	if (format.isValid())
+		GenerateData(format, durationUs, sampleRate, right);
+}
+
+void Generator::start()
+{
+	open(QIODevice::ReadOnly);
+}
+
+void Generator::stop()
+{
+	pos = 0;
+	close();
+}
+
+void Generator::GenerateData(const QAudioFormat &format, qint64 durationUs, int sampleRate, bool right)
+{
+	const int channelBytes = format.sampleSize() / 8;
+	const int sampleBytes = format.channelCount() * channelBytes;
+	qint64 length = (format.sampleRate() * format.channelCount() * (format.sampleSize() / 8))
+	                    * durationUs / 1000000;
+	Q_ASSERT(length % sampleBytes == 0);
+	Q_UNUSED(sampleBytes) // suppress warning in release builds
+
+	buffer.resize(length);
+	unsigned char *ptr = reinterpret_cast<unsigned char *>(buffer.data());
+	int sampleIndex = 0;
+
+	while (length)
+	{
+		for (int i = 0; i < format.channelCount(); ++i)
+		{
+			qreal x = 0;
+			//  Generate sine wave on first (left) or second (right) channel and silence on other.
+			if ( (i == 0 && !right) ||
+			     (i == 1 && right))
+			{
+				x = qSin(2 * M_PI * sampleRate * sampleIndex / format.sampleRate()) * 0.1;
+				sampleIndex++;
+			}
+			if (format.sampleSize() == 8)
+			{
+				if (format.sampleType() == QAudioFormat::UnSignedInt)
+				{
+					const quint8 value = static_cast<quint8>((1.0 + x) / 2 * 255);
+					*reinterpret_cast<quint8 *>(ptr) = value;
+				}
+				else if (format.sampleType() == QAudioFormat::SignedInt)
+				{
+					const qint8 value = static_cast<qint8>(x * 127);
+					*reinterpret_cast<qint8 *>(ptr) = value;
+				}
+			}
+			else if (format.sampleSize() == 16)
+			{
+				if (format.sampleType() == QAudioFormat::UnSignedInt)
+				{
+					quint16 value = static_cast<quint16>((1.0 + x) / 2 * 65535);
+					if (format.byteOrder() == QAudioFormat::LittleEndian)
+						qToLittleEndian<quint16>(value, ptr);
+					else
+						qToBigEndian<quint16>(value, ptr);
+				}
+				else if (format.sampleType() == QAudioFormat::SignedInt)
+				{
+					qint16 value = static_cast<qint16>(x * 32767);
+					if (format.byteOrder() == QAudioFormat::LittleEndian)
+						qToLittleEndian<qint16>(value, ptr);
+					else
+						qToBigEndian<qint16>(value, ptr);
+				}
+			}
+
+			ptr += channelBytes;
+			length -= channelBytes;
+		}
+	}
+}
+
+qint64 Generator::readData(char *data, qint64 len)
+{
+	qint64 total = 0;
+	if (!buffer.isEmpty())
+	{
+		while (len - total > 0)
+		{
+			const qint64 chunk = qMin((buffer.size() - pos), len - total);
+			memcpy(data + total, buffer.constData() + pos, chunk);
+			pos = (pos + chunk) % buffer.size();
+			total += chunk;
+		}
+	}
+	return total;
+}
+
+qint64 Generator::writeData(const char *data, qint64 len)
+{
+	Q_UNUSED(data);
+	Q_UNUSED(len);
+
+	return 0;
+}
+
+qint64 Generator::bytesAvailable() const
+{
+	return buffer.size() + QIODevice::bytesAvailable();
+}