void SignalDataSource::setSamples(float *samples,
qint64 count,
double sampleRate)
{
clean();
m_samples = samples;
m_count = count;
m_sampleRate = sampleRate;
qint64 spp = 2;
while (m_count / spp > 0) {
qint64 count = m_count / spp + ((m_count % spp) ? (1) : (0));
float *maximums;
float *minimums;
{
QTemporaryFile *file = new QTemporaryFile();
if (!file->open())
return ;
file->resize(count * sizeof(float));
maximums = (float *)(file->map(0, count * sizeof(float)));
}
{
QTemporaryFile *file = new QTemporaryFile();
if (!file->open())
return ;
file->resize(count * sizeof(float));
minimums = (float *)(file->map(0, count * sizeof(float)));
}
for (qint64 arrIndex = 0; arrIndex < count; ++arrIndex) {
qint64 sampleFirstIndex = arrIndex * spp;
qint64 sampleLastIndex = sampleFirstIndex + spp - 1;
if (sampleLastIndex >= m_count)
sampleLastIndex = m_count - 1;
double min;
double max;
min = max = m_samples[sampleFirstIndex];
for (int i = sampleFirstIndex + 1; i <= sampleLastIndex; ++i) {
if (m_samples[i] < min)
min = m_samples[i];
else if (m_samples[i] > max)
max = m_samples[i];
}
minimums[arrIndex] = min;
maximums[arrIndex] = max;
}
m_peakMaximums[spp] = maximums;
m_peakMinimums[spp] = minimums;
m_peakCount[spp] = count;
spp *= 2;
}
emit dataChanged();
}
