/*
* Copyright (C) 2003-2010 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.
*/
#ifndef MPD_CROSSFADE_H
#define MPD_CROSSFADE_H
struct audio_format;
struct music_chunk;
/**
* Calculate how many music pipe chunks should be used for crossfading.
*
* @param duration the requested crossfade duration
* @param total_time total_time the duration of the new song
* @param mixramp_db the current mixramp_db setting
* @param mixramp_delay the current mixramp_delay setting
* @param mixramp_start the next songs mixramp_start tag
* @param mixramp_prev_end the last songs mixramp_end setting
* @param af the audio format of the new song
* @param old_format the audio format of the current song
* @param max_chunks the maximum number of chunks
* @return the number of chunks for crossfading, or 0 if cross fading
* should be disabled for this song change
*/
unsigned cross_fade_calc(float duration, float total_time,
float mixramp_db, float mixramp_delay,
char *mixramp_start, char *mixramp_prev_end,
const struct audio_format *af,
const struct audio_format *old_format,
unsigned max_chunks);
/**
* Applies cross fading to two chunks, i.e. mixes these chunks.
* Internally, this calls pcm_mix().
*
* @param a the chunk in the current song (and the destination chunk)
* @param b the according chunk in the new song
* @param format the audio format of both chunks (must be the same)
* @param current_chunk the relative index of the current chunk
* @param num_chunks the number of chunks used for cross fading
*/
void cross_fade_apply(struct music_chunk *a, const struct music_chunk *b,
const struct audio_format *format,
float mix_ratio);
#endif
