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Diffstat (limited to 'src/filter/volume_filter_plugin.c')
-rw-r--r-- | src/filter/volume_filter_plugin.c | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/src/filter/volume_filter_plugin.c b/src/filter/volume_filter_plugin.c new file mode 100644 index 000000000..82eed3acc --- /dev/null +++ b/src/filter/volume_filter_plugin.c @@ -0,0 +1,162 @@ +/* + * Copyright (C) 2003-2009 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 "filter/volume_filter_plugin.h" +#include "filter_plugin.h" +#include "filter_internal.h" +#include "filter_registry.h" +#include "conf.h" +#include "pcm_buffer.h" +#include "pcm_volume.h" +#include "audio_format.h" +#include "player_control.h" + +#include <assert.h> +#include <string.h> + +struct volume_filter { + struct filter filter; + + /** + * The current volume, from 0 to #PCM_VOLUME_1. + */ + unsigned volume; + + struct audio_format audio_format; + + struct pcm_buffer buffer; +}; + +static inline GQuark +volume_quark(void) +{ + return g_quark_from_static_string("pcm_volume"); +} + +static struct filter * +volume_filter_init(G_GNUC_UNUSED const struct config_param *param, + G_GNUC_UNUSED GError **error_r) +{ + struct volume_filter *filter = g_new(struct volume_filter, 1); + + filter_init(&filter->filter, &volume_filter_plugin); + filter->volume = PCM_VOLUME_1; + + return &filter->filter; +} + +static void +volume_filter_finish(struct filter *filter) +{ + g_free(filter); +} + +static const struct audio_format * +volume_filter_open(struct filter *_filter, struct audio_format *audio_format, + G_GNUC_UNUSED GError **error_r) +{ + struct volume_filter *filter = (struct volume_filter *)_filter; + + audio_format->reverse_endian = false; + + filter->audio_format = *audio_format; + pcm_buffer_init(&filter->buffer); + + return &filter->audio_format; +} + +static void +volume_filter_close(struct filter *_filter) +{ + struct volume_filter *filter = (struct volume_filter *)_filter; + + pcm_buffer_deinit(&filter->buffer); +} + +static const void * +volume_filter_filter(struct filter *_filter, const void *src, size_t src_size, + size_t *dest_size_r, GError **error_r) +{ + struct volume_filter *filter = (struct volume_filter *)_filter; + bool success; + void *dest; + + if (filter->volume >= PCM_VOLUME_1) { + /* optimized special case: 100% volume = no-op */ + *dest_size_r = src_size; + return src; + } + + dest = pcm_buffer_get(&filter->buffer, src_size); + *dest_size_r = src_size; + + if (filter->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); + + success = pcm_volume(dest, src_size, &filter->audio_format, + filter->volume); + if (!success) { + g_set_error(error_r, volume_quark(), 0, + "pcm_volume() has failed"); + return NULL; + } + + return dest; +} + +const struct filter_plugin volume_filter_plugin = { + .name = "volume", + .init = volume_filter_init, + .finish = volume_filter_finish, + .open = volume_filter_open, + .close = volume_filter_close, + .filter = volume_filter_filter, +}; + +unsigned +volume_filter_get(const struct filter *_filter) +{ + const struct volume_filter *filter = + (const struct volume_filter *)_filter; + + assert(filter->filter.plugin == &volume_filter_plugin); + assert(filter->volume <= PCM_VOLUME_1); + + return filter->volume; +} + +void +volume_filter_set(struct filter *_filter, unsigned volume) +{ + struct volume_filter *filter = (struct volume_filter *)_filter; + + assert(filter->filter.plugin == &volume_filter_plugin); + assert(volume <= PCM_VOLUME_1); + + filter->volume = volume; +} + |