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livetrax/libs/audiographer/src/general/normalizer.cc

90 lines
2.3 KiB
C++

/*
Copyright (C) 2012 Paul Davis
Author: Sakari Bergen
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "audiographer/general/normalizer.h"
namespace AudioGrapher
{
Normalizer::Normalizer (float target_dB)
: enabled (false)
, buffer (0)
, buffer_size (0)
{
target = pow (10.0f, target_dB * 0.05f);
}
Normalizer::~Normalizer()
{
delete [] buffer;
}
/// Sets the peak found in the material to be normalized \see PeakReader \n RT safe
float Normalizer::set_peak (float peak)
{
if (peak == 0.0f || peak == target) {
/* don't even try */
enabled = false;
} else {
enabled = true;
gain = target / peak;
}
return enabled ? gain : 1.0;
}
/** Allocates a buffer for using with const ProcessContexts
* This function does not need to be called if
* non-const ProcessContexts are given to \a process() .
* \n Not RT safe
*/
void Normalizer::alloc_buffer(framecnt_t frames)
{
delete [] buffer;
buffer = new float[frames];
buffer_size = frames;
}
/// Process a const ProcessContext \see alloc_buffer() \n RT safe
void Normalizer::process (ProcessContext<float> const & c)
{
if (throw_level (ThrowProcess) && c.frames() > buffer_size) {
throw Exception (*this, "Too many frames given to process()");
}
if (enabled) {
memcpy (buffer, c.data(), c.frames() * sizeof(float));
Routines::apply_gain_to_buffer (buffer, c.frames(), gain);
}
ProcessContext<float> c_out (c, buffer);
ListedSource<float>::output (c_out);
}
/// Process a non-const ProcsesContext in-place \n RT safe
void Normalizer::process (ProcessContext<float> & c)
{
if (enabled) {
Routines::apply_gain_to_buffer (c.data(), c.frames(), gain);
}
ListedSource<float>::output(c);
}
} // namespace