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/*
* Copyright 2008-2013 Various Authors
* Copyright 2004 Timo Hirvonen
*
* 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, see <http://www.gnu.org/licenses/>.
*/
#include "pcm.h"
#include "utils.h"
#include <stdint.h>
#include <stdlib.h>
/*
* Functions to convert PCM to 16-bit signed little-endian stereo
*
* Conversion for 8-bit PCM):
* 1. phase
* unsigned -> signed
* mono -> stereo
* 8 -> 16
*
* Conversion for 16-bit PCM:
* 1. phase
* be -> le
* unsigned -> signed
*
* 2. phase
* mono -> stereo
*
* There's no reason to split 8-bit conversion to 2 phases because we need to
* use separate buffer for 8->16 conversion anyway.
*
* Conversions for 16-bit stereo can be done in place. 16-bit mono needs to be
* converted to stereo so it's worthwhile to split the conversion to 2 phases.
*/
static void convert_u8_1ch_to_s16_2ch(void *dst, const void *src, int count)
{
int16_t *d = dst;
const uint8_t *s = src;
int i, j = 0;
for (i = 0; i < count; i++) {
int16_t sample = s[i] << 8;
sample -= 32768;
d[j++] = sample;
d[j++] = sample;
}
}
static void convert_s8_1ch_to_s16_2ch(void *dst, const void *src, int count)
{
int16_t *d = dst;
const int8_t *s = src;
int i, j = 0;
for (i = 0; i < count; i++) {
int16_t sample = s[i] << 8;
d[j++] = sample;
d[j++] = sample;
}
}
static void convert_u8_2ch_to_s16_2ch(void *dst, const void *src, int count)
{
int16_t *d = dst;
const int8_t *s = src;
int i;
for (i = 0; i < count; i++) {
int16_t sample = s[i] << 8;
sample -= 32768;
d[i] = sample;
}
}
static void convert_s8_2ch_to_s16_2ch(void *dst, const void *src, int count)
{
int16_t *d = dst;
const int8_t *s = src;
int i;
for (i = 0; i < count; i++) {
int16_t sample = s[i] << 8;
d[i] = sample;
}
}
static void convert_u16_le_to_s16_le(void *buf, int count)
{
int16_t *b = buf;
int i;
for (i = 0; i < count; i++) {
int sample = (uint16_t)b[i];
sample -= 32768;
b[i] = sample;
}
}
static void convert_u16_be_to_s16_le(void *buf, int count)
{
int16_t *b = buf;
int i;
for (i = 0; i < count; i++) {
uint16_t u = b[i];
int sample;
u = swap_uint16(u);
sample = (int)u - 32768;
b[i] = sample;
}
}
static void swap_s16_byte_order(void *buf, int count)
{
int16_t *b = buf;
int i;
for (i = 0; i < count; i++)
b[i] = swap_uint16(b[i]);
}
static void convert_16_1ch_to_16_2ch(void *dst, const void *src, int count)
{
int16_t *d = dst;
const int16_t *s = src;
int i, j = 0;
for (i = 0; i < count; i++) {
d[j++] = s[i];
d[j++] = s[i];
}
}
/* index is ((bits >> 2) & 4) | (is_signed << 1) | (channels - 1) */
pcm_conv_func pcm_conv[8] = {
convert_u8_1ch_to_s16_2ch,
convert_u8_2ch_to_s16_2ch,
convert_s8_1ch_to_s16_2ch,
convert_s8_2ch_to_s16_2ch,
convert_16_1ch_to_16_2ch,
NULL,
convert_16_1ch_to_16_2ch,
NULL
};
/* index is ((bits >> 2) & 4) | (is_signed << 1) | bigendian */
pcm_conv_in_place_func pcm_conv_in_place[8] = {
NULL,
NULL,
NULL,
NULL,
convert_u16_le_to_s16_le,
convert_u16_be_to_s16_le,
#ifdef WORDS_BIGENDIAN
swap_s16_byte_order,
NULL,
#else
NULL,
swap_s16_byte_order,
#endif
};
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