// Remove DC offset
float RemoveDCOffset(modplug::tracker::modsample_t& smp,
SmpLength iStart,
SmpLength iEnd,
const MODTYPE modtype,
module_renderer* const pSndFile)
//----------------------------------------------
{
if(smp.sample_data == nullptr || smp.length < 1)
return 0;
modplug::tracker::modsample_t* const pSmp = &smp;
if (iEnd > pSmp->length) iEnd = pSmp->length;
if (iStart > iEnd) iStart = iEnd;
if (iStart == iEnd)
{
iStart = 0;
iEnd = pSmp->length;
}
iStart *= pSmp->GetNumChannels();
iEnd *= pSmp->GetNumChannels();
const double dMaxAmplitude = (pSmp->GetElementarySampleSize() == 2) ? GetMaxAmplitude<int16_t>() : GetMaxAmplitude<int8_t>();
// step 1: Calculate offset.
OffsetData oData = {0,0,0};
if(pSmp->GetElementarySampleSize() == 2)
oData = CalculateOffset(reinterpret_cast<int16_t*>(pSmp->sample_data) + iStart, iEnd - iStart);
else if(pSmp->GetElementarySampleSize() == 1)
oData = CalculateOffset(reinterpret_cast<int8_t*>(pSmp->sample_data) + iStart, iEnd - iStart);
double dMin = oData.dMin, dMax = oData.dMax, dOffset = oData.dOffset;
const float fReportOffset = (float)dOffset;
if((int)(dOffset * dMaxAmplitude) == 0)
return 0;
// those will be changed...
dMax += dOffset;
dMin += dOffset;
// ... and that might cause distortion, so we will normalize this.
const double dAmplify = 1 / bad_max(dMax, -dMin);
// step 2: centralize + normalize sample
dOffset *= dMaxAmplitude * dAmplify;
if(pSmp->GetElementarySampleSize() == 2)
RemoveOffsetAndNormalize( reinterpret_cast<int16_t*>(pSmp->sample_data) + iStart, iEnd - iStart, dOffset, dAmplify);
else if(pSmp->GetElementarySampleSize() == 1)
RemoveOffsetAndNormalize( reinterpret_cast<int8_t*>(pSmp->sample_data) + iStart, iEnd - iStart, dOffset, dAmplify);
// step 3: adjust global vol (if available)
if((modtype & (MOD_TYPE_IT | MOD_TYPE_MPT)) && (iStart == 0) && (iEnd == pSmp->length * pSmp->GetNumChannels()))
{
BEGIN_CRITICAL();
pSmp->global_volume = bad_min((uint16_t)(pSmp->global_volume / dAmplify), 64);
for (modplug::tracker::chnindex_t i = 0; i < MAX_VIRTUAL_CHANNELS; i++)
{
if(pSndFile->Chn[i].sample_data == pSmp->sample_data)
{
pSndFile->Chn[i].nGlobalVol = pSmp->global_volume;
}
}
END_CRITICAL();
}
AdjustEndOfSample(smp, pSndFile);
return fReportOffset;
}
// Remove DC offset
float RemoveDCOffset(ModSample &smp,
SmpLength iStart,
SmpLength iEnd,
const MODTYPE modtype,
CSoundFile &sndFile)
//---------------------------------------
{
if(smp.pSample == nullptr || smp.nLength < 1)
return 0;
if (iEnd > smp.nLength) iEnd = smp.nLength;
if (iStart > iEnd) iStart = iEnd;
if (iStart == iEnd)
{
iStart = 0;
iEnd = smp.nLength;
}
iStart *= smp.GetNumChannels();
iEnd *= smp.GetNumChannels();
const double dMaxAmplitude = (smp.GetElementarySampleSize() == 2) ? GetMaxAmplitude<int16>() : GetMaxAmplitude<int8>();
// step 1: Calculate offset.
OffsetData oData = {0,0,0};
if(smp.GetElementarySampleSize() == 2)
oData = CalculateOffset(static_cast<int16 *>(smp.pSample) + iStart, iEnd - iStart);
else if(smp.GetElementarySampleSize() == 1)
oData = CalculateOffset(static_cast<int8*>(smp.pSample) + iStart, iEnd - iStart);
double dMin = oData.dMin, dMax = oData.dMax, dOffset = oData.dOffset;
const float fReportOffset = (float)dOffset;
if((int)(dOffset * dMaxAmplitude) == 0)
return 0;
// those will be changed...
dMax += dOffset;
dMin += dOffset;
// ... and that might cause distortion, so we will normalize this.
const double dAmplify = 1 / MAX(dMax, -dMin);
// step 2: centralize + normalize sample
dOffset *= dMaxAmplitude * dAmplify;
if(smp.GetElementarySampleSize() == 2)
RemoveOffsetAndNormalize( static_cast<int16 *>(smp.pSample) + iStart, iEnd - iStart, dOffset, dAmplify);
else if(smp.GetElementarySampleSize() == 1)
RemoveOffsetAndNormalize( static_cast<int8 *>(smp.pSample) + iStart, iEnd - iStart, dOffset, dAmplify);
// step 3: adjust global vol (if available)
if((modtype & (MOD_TYPE_IT | MOD_TYPE_MPT)) && (iStart == 0) && (iEnd == smp.nLength * smp.GetNumChannels()))
{
CriticalSection cs;
smp.nGlobalVol = std::min((uint16)(smp.nGlobalVol / dAmplify), uint16(64));
for (CHANNELINDEX i = 0; i < MAX_CHANNELS; i++)
{
if(sndFile.m_PlayState.Chn[i].pModSample == &smp)
{
sndFile.m_PlayState.Chn[i].nInsVol = smp.nGlobalVol;
if(sndFile.m_PlayState.Chn[i].pModInstrument)
{
sndFile.m_PlayState.Chn[i].nInsVol = (smp.nGlobalVol * sndFile.m_PlayState.Chn[i].pModInstrument->nGlobalVol) >> 6;
}
}