From 0078837a9760b8b5a14c87af0cb44a107462db7b Mon Sep 17 00:00:00 2001 From: Max Kellermann Date: Thu, 23 Oct 2008 16:58:07 +0200 Subject: pcm_dither: added generic 24 to 16 bit dithering Copied and adapted code from the mp3 decoder plugin. This library now replaces the old and low-quality function pcm_convert_24_to_16(). --- src/pcm_dither.h | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 src/pcm_dither.h (limited to 'src/pcm_dither.h') diff --git a/src/pcm_dither.h b/src/pcm_dither.h new file mode 100644 index 000000000..202521497 --- /dev/null +++ b/src/pcm_dither.h @@ -0,0 +1,41 @@ +/* the Music Player Daemon (MPD) + * Copyright (C) 2008 Max Kellermann + * This project's homepage is: 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#ifndef PCM_DITHER_H +#define PCM_DITHER_H + +#include + +struct pcm_dither_24 { + int32_t error[3]; + int32_t random; +}; + +static inline void +pcm_dither_24_init(struct pcm_dither_24 *dither) +{ + dither->error[0] = dither->error[1] = dither->error[2] = 0; + dither->random = 0; +} + +void +pcm_dither_24_to_16(struct pcm_dither_24 *dither, + int16_t *dest, const int32_t *src, + unsigned num_samples); + +#endif -- cgit v1.2.3