/*
* Copyright (C) 2003-2013 The Music Player Daemon Project
* http://www.musicpd.org
*
* 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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#include "SoxrResampler.hxx"
#include "AudioFormat.hxx"
#include "util/ASCII.hxx"
#include "util/Error.hxx"
#include "util/Domain.hxx"
#include "Log.hxx"
#include <soxr.h>
#include <assert.h>
static constexpr Domain soxr_domain("soxr");
AudioFormat
SoxrPcmResampler::Open(AudioFormat &af, unsigned new_sample_rate,
Error &error)
{
assert(af.IsValid());
assert(audio_valid_sample_rate(new_sample_rate));
soxr_error_t e;
soxr = soxr_create(af.sample_rate, new_sample_rate,
af.channels, &e,
nullptr, nullptr, nullptr);
if (soxr == nullptr) {
error.Format(soxr_domain,
"soxr initialization has failed: %s", e);
return AudioFormat::Undefined();
}
FormatDebug(soxr_domain, "soxr engine '%s'", soxr_engine(soxr));
channels = af.channels;
ratio = float(new_sample_rate) / float(af.sample_rate);
FormatDebug(soxr_domain,
"samplerate conversion ratio to %.2lf",
ratio);
/* libsoxr works with floating point samples */
af.format = SampleFormat::FLOAT;
AudioFormat result = af;
result.sample_rate = new_sample_rate;
return result;
}
void
SoxrPcmResampler::Close()
{
soxr_delete(soxr);
}
ConstBuffer<void>
SoxrPcmResampler::Resample(ConstBuffer<void> src, Error &error)
{
const size_t frame_size = channels * sizeof(float);
assert(src.size % frame_size == 0);
const size_t n_frames = src.size / frame_size;
const size_t o_frames = size_t(n_frames * ratio + 0.5);
float *output_buffer = (float *)buffer.Get(o_frames * frame_size);
size_t i_done, o_done;
soxr_error_t e = soxr_process(soxr, src.data, n_frames, &i_done,
output_buffer, o_frames, &o_done);
if (e != nullptr) {
error.Format(soxr_domain, "soxr error: %s", e);
return nullptr;
}
return { output_buffer, o_done * frame_size };
}