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/*
* 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.
*/
#ifndef MPD_PCM_RESAMPLE_H
#define MPD_PCM_RESAMPLE_H
#include "pcm_buffer.h"
#include "config.h"
#include <stdint.h>
#include <stddef.h>
#include <stdbool.h>
#ifdef HAVE_LIBSAMPLERATE
#include <samplerate.h>
#endif
/**
* This object is statically allocated (within another struct), and
* holds buffer allocations and the state for the resampler.
*/
struct pcm_resample_state {
#ifdef HAVE_LIBSAMPLERATE
SRC_STATE *state;
SRC_DATA data;
struct pcm_buffer in, out;
struct {
unsigned src_rate;
unsigned dest_rate;
uint8_t channels;
} prev;
bool error;
#endif
struct pcm_buffer buffer;
};
/**
* Initializes a pcm_resample_state object.
*/
void pcm_resample_init(struct pcm_resample_state *state);
/**
* Deinitializes a pcm_resample_state object and frees allocated
* memory.
*/
void pcm_resample_deinit(struct pcm_resample_state *state);
/**
* Resamples 16 bit PCM data.
*
* @param state an initialized pcm_resample_state object
* @param channels the number of channels
* @param src_rate the source sample rate
* @param src the source PCM buffer
* @param src_size the size of #src in bytes
* @param dest_rate the requested destination sample rate
* @param dest_size_r returns the number of bytes of the destination buffer
* @return the destination buffer
*/
const int16_t *
pcm_resample_16(struct pcm_resample_state *state,
uint8_t channels,
unsigned src_rate,
const int16_t *src_buffer, size_t src_size,
unsigned dest_rate,
size_t *dest_size_r);
/**
* Resamples 32 bit PCM data.
*
* @param state an initialized pcm_resample_state object
* @param channels the number of channels
* @param src_rate the source sample rate
* @param src the source PCM buffer
* @param src_size the size of #src in bytes
* @param dest_rate the requested destination sample rate
* @param dest_size_r returns the number of bytes of the destination buffer
* @return the destination buffer
*/
const int32_t *
pcm_resample_32(struct pcm_resample_state *state,
uint8_t channels,
unsigned src_rate,
const int32_t *src_buffer, size_t src_size,
unsigned dest_rate,
size_t *dest_size_r);
/**
* Resamples 24 bit PCM data.
*
* @param state an initialized pcm_resample_state object
* @param channels the number of channels
* @param src_rate the source sample rate
* @param src the source PCM buffer
* @param src_size the size of #src in bytes
* @param dest_rate the requested destination sample rate
* @param dest_size_r returns the number of bytes of the destination buffer
* @return the destination buffer
*/
static inline const int32_t *
pcm_resample_24(struct pcm_resample_state *state,
uint8_t channels,
unsigned src_rate,
const int32_t *src_buffer, size_t src_size,
unsigned dest_rate,
size_t *dest_size_r)
{
/* reuse the 32 bit code - the resampler code doesn't care if
the upper 8 bits are actually used */
return pcm_resample_32(state, channels,
src_rate, src_buffer, src_size,
dest_rate, dest_size_r);
}
#endif
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