/*
* 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 "VolumeFilterPlugin.hxx"
#include "FilterPlugin.hxx"
#include "FilterInternal.hxx"
#include "FilterRegistry.hxx"
#include "pcm/Volume.hxx"
#include "pcm/PcmBuffer.hxx"
#include "AudioFormat.hxx"
#include "util/Error.hxx"
#include "util/Domain.hxx"
#include <assert.h>
#include <string.h>
class VolumeFilter final : public Filter {
/**
* The current volume, from 0 to #PCM_VOLUME_1.
*/
unsigned volume;
AudioFormat format;
PcmBuffer buffer;
public:
VolumeFilter()
:volume(PCM_VOLUME_1) {}
unsigned GetVolume() const {
assert(volume <= PCM_VOLUME_1);
return volume;
}
void SetVolume(unsigned _volume) {
assert(_volume <= PCM_VOLUME_1);
volume = _volume;
}
virtual AudioFormat Open(AudioFormat &af, Error &error) override;
virtual void Close();
virtual const void *FilterPCM(const void *src, size_t src_size,
size_t *dest_size_r, Error &error);
};
static constexpr Domain volume_domain("pcm_volume");
static Filter *
volume_filter_init(gcc_unused const config_param ¶m,
gcc_unused Error &error)
{
return new VolumeFilter();
}
AudioFormat
VolumeFilter::Open(AudioFormat &audio_format, gcc_unused Error &error)
{
format = audio_format;
return format;
}
void
VolumeFilter::Close()
{
buffer.Clear();
}
const void *
VolumeFilter::FilterPCM(const void *src, size_t src_size,
size_t *dest_size_r, Error &error)
{
*dest_size_r = src_size;
if (volume >= PCM_VOLUME_1)
/* optimized special case: 100% volume = no-op */
return src;
void *dest = buffer.Get(src_size);
if (volume <= 0) {
/* optimized special case: 0% volume = memset(0) */
/* XXX is this valid for all sample formats? What
about floating point? */
memset(dest, 0, src_size);
return dest;
}
memcpy(dest, src, src_size);
bool success = pcm_volume(dest, src_size,
format.format,
volume);
if (!success) {
error.Set(volume_domain, "pcm_volume() has failed");
return NULL;
}
return dest;
}
const struct filter_plugin volume_filter_plugin = {
"volume",
volume_filter_init,
};
unsigned
volume_filter_get(const Filter *_filter)
{
const VolumeFilter *filter =
(const VolumeFilter *)_filter;
return filter->GetVolume();
}
void
volume_filter_set(Filter *_filter, unsigned volume)
{
VolumeFilter *filter = (VolumeFilter *)_filter;
filter->SetVolume(volume);
}