Send usigned data and simplify downdamplign code

This commit is contained in:
Geoffrey Merck 2020-05-13 12:42:14 +02:00
parent fa9f89700f
commit 81f6b6be53
2 changed files with 24 additions and 31 deletions

View File

@ -25,43 +25,38 @@ CFMDownsampler::CFMDownsampler(uint16_t length) :
m_ringBuffer(length),
m_samplePack(0U),
m_samplePackPointer(NULL),
m_packIndex(0U),
m_downSampleIndex(0U)
m_sampleIndex(0U)
{
m_samplePackPointer = (uint8_t*)&m_samplePack;
}
void CFMDownsampler::addSample(q15_t sample)
{
//only take one of three samples
if(m_downSampleIndex == 0U) {
switch(m_packIndex){
case 0:
m_samplePack = uint32_t(sample) << 12;
break;
case 1:{
m_samplePack |= uint32_t(sample);
//we did not use MSB; skip it
TSamplePairPack pair{m_samplePackPointer[1U], m_samplePackPointer[2U], m_samplePackPointer[3U]};
uint16_t usample = uint16_t(sample + 2048);
//only take one of three samples
switch(m_sampleIndex){
case 0:
m_samplePack = uint32_t(usample) << 12;
break;
case 3:{
m_samplePack |= uint32_t(usample);
//we did not use MSB; skip it
TSamplePairPack pair{m_samplePackPointer[1U], m_samplePackPointer[2U], m_samplePackPointer[3U]};
m_ringBuffer.put(pair);
m_ringBuffer.put(pair);
m_samplePack = 0;//reset the sample pack
}
break;
default:
//should never happen
break;
}
m_packIndex++;
if(m_packIndex >= 2U)//did we pack two samples ?
m_packIndex = 0U;
m_samplePack = 0U;//reset the sample pack
}
break;
default:
//Just skip this sample
break;
}
m_downSampleIndex++;
if(m_downSampleIndex >= 3U)
m_downSampleIndex = 0U;
m_sampleIndex++;
if(m_sampleIndex >= 6U)//did we pack two samples ?
m_sampleIndex = 0U;
}
bool CFMDownsampler::getPackedData(TSamplePairPack& data)
@ -76,6 +71,5 @@ uint16_t CFMDownsampler::getData()
void CFMDownsampler::reset()
{
m_downSampleIndex = 0;
m_packIndex = 0;
m_sampleIndex = 0U;
}

View File

@ -38,8 +38,7 @@ private:
uint32_t m_samplePack;
uint8_t *m_samplePackPointer;
uint8_t m_packIndex;
uint8_t m_downSampleIndex;
uint8_t m_sampleIndex;
};
#endif