diff options
Diffstat (limited to 'intern/audaspace/FX/AUD_HighpassReader.cpp')
| -rw-r--r-- | intern/audaspace/FX/AUD_HighpassReader.cpp | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/intern/audaspace/FX/AUD_HighpassReader.cpp b/intern/audaspace/FX/AUD_HighpassReader.cpp new file mode 100644 index 00000000000..8240854fc06 --- /dev/null +++ b/intern/audaspace/FX/AUD_HighpassReader.cpp @@ -0,0 +1,112 @@ +/* + * $Id$ + * + * ***** BEGIN LGPL LICENSE BLOCK ***** + * + * Copyright 2009 Jörg Hermann Müller + * + * This file is part of AudaSpace. + * + * AudaSpace is free software: you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * AudaSpace is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public License + * along with AudaSpace. If not, see <http://www.gnu.org/licenses/>. + * + * ***** END LGPL LICENSE BLOCK ***** + */ + +#include "AUD_HighpassReader.h" +#include "AUD_Buffer.h" + +#include <cstring> +#include <cmath> + +#define CC channels + channel + +AUD_HighpassReader::AUD_HighpassReader(AUD_IReader* reader, float frequency, + float Q) : + AUD_EffectReader(reader) +{ + AUD_Specs specs = reader->getSpecs(); + int samplesize = AUD_SAMPLE_SIZE(specs); + + m_buffer = new AUD_Buffer(); AUD_NEW("buffer") + + m_outvalues = new AUD_Buffer(samplesize * AUD_HIGHPASS_ORDER); + AUD_NEW("buffer") + memset(m_outvalues->getBuffer(), 0, samplesize * AUD_HIGHPASS_ORDER); + + m_invalues = new AUD_Buffer(samplesize * AUD_HIGHPASS_ORDER); + AUD_NEW("buffer") + memset(m_invalues->getBuffer(), 0, samplesize * AUD_HIGHPASS_ORDER); + + m_position = 0; + + // calculate coefficients + float w0 = 2.0 * M_PI * frequency / specs.rate; + float alpha = sin(w0) / (2 * Q); + float norm = 1 + alpha; + m_coeff[0][0] = 0; + m_coeff[0][1] = -2 * cos(w0) / norm; + m_coeff[0][2] = (1 - alpha) / norm; + m_coeff[1][2] = m_coeff[1][0] = (1 + cos(w0)) / (2 * norm); + m_coeff[1][1] = (-1 - cos(w0)) / norm; +} + +AUD_HighpassReader::~AUD_HighpassReader() +{ + delete m_buffer; AUD_DELETE("buffer") + + delete m_outvalues; AUD_DELETE("buffer") + delete m_invalues; AUD_DELETE("buffer"); +} + +void AUD_HighpassReader::read(int & length, sample_t* & buffer) +{ + sample_t* buf; + sample_t* outvalues; + sample_t* invalues; + + outvalues = m_outvalues->getBuffer(); + invalues = m_invalues->getBuffer(); + + AUD_Specs specs = m_reader->getSpecs(); + + m_reader->read(length, buf); + + if(m_buffer->getSize() < length * AUD_SAMPLE_SIZE(specs)) + m_buffer->resize(length * AUD_SAMPLE_SIZE(specs)); + + buffer = m_buffer->getBuffer(); + int channels = specs.channels; + + for(int channel = 0; channel < channels; channel++) + { + for(int i = 0; i < length; i++) + { + invalues[m_position * CC] = buf[i * CC]; + outvalues[m_position * CC] = 0; + + for(int j = 0; j < AUD_HIGHPASS_ORDER; j++) + { + outvalues[m_position * CC] += m_coeff[1][j] * + invalues[((m_position + j) % AUD_HIGHPASS_ORDER) * CC] - + m_coeff[0][j] * + outvalues[((m_position + j) % AUD_HIGHPASS_ORDER) * CC]; + } + + buffer[i * CC] = outvalues[m_position * CC]; + + m_position = (m_position + AUD_HIGHPASS_ORDER-1) % + AUD_HIGHPASS_ORDER; + } + } +} |