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alsa-lib/src/pcm/pcm_misc.c
Jaroslav Kysela 853304bbf4 Corrections by Kevin Conder <kconder@interaccess.com>
2002-03-12 20:14:33 +00:00

540 lines
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/*
* PCM Interface - misc routines
* Copyright (c) 1998 by Jaroslav Kysela <perex@suse.cz>
*
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <byteswap.h>
#include "pcm_local.h"
/**
* \brief Return sign info for a PCM sample linear format
* \param format Format
* \return 0 unsigned, 1 signed, a negative error code if format is not linear
*/
int snd_pcm_format_signed(snd_pcm_format_t format)
{
switch (format) {
case SNDRV_PCM_FORMAT_S8:
case SNDRV_PCM_FORMAT_S16_LE:
case SNDRV_PCM_FORMAT_S16_BE:
case SNDRV_PCM_FORMAT_S24_LE:
case SNDRV_PCM_FORMAT_S24_BE:
case SNDRV_PCM_FORMAT_S32_LE:
case SNDRV_PCM_FORMAT_S32_BE:
return 1;
case SNDRV_PCM_FORMAT_U8:
case SNDRV_PCM_FORMAT_U16_LE:
case SNDRV_PCM_FORMAT_U16_BE:
case SNDRV_PCM_FORMAT_U24_LE:
case SNDRV_PCM_FORMAT_U24_BE:
case SNDRV_PCM_FORMAT_U32_LE:
case SNDRV_PCM_FORMAT_U32_BE:
return 0;
default:
return -EINVAL;
}
}
/**
* \brief Return sign info for a PCM sample linear format
* \param format Format
* \return 0 signed, 1 unsigned, a negative error code if format is not linear
*/
int snd_pcm_format_unsigned(snd_pcm_format_t format)
{
int val;
val = snd_pcm_format_signed(format);
if (val < 0)
return val;
return !val;
}
/**
* \brief Return linear info for a PCM sample format
* \param format Format
* \return 0 non linear, 1 linear
*/
int snd_pcm_format_linear(snd_pcm_format_t format)
{
return snd_pcm_format_signed(format) >= 0;
}
/**
* \brief Return float info for a PCM sample format
* \param format Format
* \return 0 non float, 1 float
*/
int snd_pcm_format_float(snd_pcm_format_t format)
{
switch (format) {
case SNDRV_PCM_FORMAT_FLOAT_LE:
case SNDRV_PCM_FORMAT_FLOAT_BE:
case SNDRV_PCM_FORMAT_FLOAT64_LE:
case SNDRV_PCM_FORMAT_FLOAT64_BE:
return 1;
default:
return 0;
}
}
/**
* \brief Return endian info for a PCM sample format
* \param format Format
* \return 0 big endian, 1 little endian, a negative error code if endian independent
*/
int snd_pcm_format_little_endian(snd_pcm_format_t format)
{
switch (format) {
case SNDRV_PCM_FORMAT_S16_LE:
case SNDRV_PCM_FORMAT_U16_LE:
case SNDRV_PCM_FORMAT_S24_LE:
case SNDRV_PCM_FORMAT_U24_LE:
case SNDRV_PCM_FORMAT_S32_LE:
case SNDRV_PCM_FORMAT_U32_LE:
case SNDRV_PCM_FORMAT_FLOAT_LE:
case SNDRV_PCM_FORMAT_FLOAT64_LE:
case SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE:
return 1;
case SNDRV_PCM_FORMAT_S16_BE:
case SNDRV_PCM_FORMAT_U16_BE:
case SNDRV_PCM_FORMAT_S24_BE:
case SNDRV_PCM_FORMAT_U24_BE:
case SNDRV_PCM_FORMAT_S32_BE:
case SNDRV_PCM_FORMAT_U32_BE:
case SNDRV_PCM_FORMAT_FLOAT_BE:
case SNDRV_PCM_FORMAT_FLOAT64_BE:
case SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE:
return 0;
default:
return -EINVAL;
}
}
/**
* \brief Return endian info for a PCM sample format
* \param format Format
* \return 0 little endian, 1 big endian, a negative error code if endian independent
*/
int snd_pcm_format_big_endian(snd_pcm_format_t format)
{
int val;
val = snd_pcm_format_little_endian(format);
if (val < 0)
return val;
return !val;
}
/**
* \brief Return endian info for a PCM sample format
* \param format Format
* \return 0 swapped, 1 CPU endian, a negative error code if endian independent
*/
int snd_pcm_format_cpu_endian(snd_pcm_format_t format)
{
#ifdef SNDRV_LITTLE_ENDIAN
return snd_pcm_format_little_endian(format);
#else
return snd_pcm_format_big_endian(format);
#endif
}
/**
* \brief Return nominal bits per a PCM sample
* \param format Sample format
* \return bits per sample, a negative error code if not applicable
*/
int snd_pcm_format_width(snd_pcm_format_t format)
{
switch (format) {
case SNDRV_PCM_FORMAT_S8:
case SNDRV_PCM_FORMAT_U8:
return 8;
case SNDRV_PCM_FORMAT_S16_LE:
case SNDRV_PCM_FORMAT_S16_BE:
case SNDRV_PCM_FORMAT_U16_LE:
case SNDRV_PCM_FORMAT_U16_BE:
return 16;
case SNDRV_PCM_FORMAT_S24_LE:
case SNDRV_PCM_FORMAT_S24_BE:
case SNDRV_PCM_FORMAT_U24_LE:
case SNDRV_PCM_FORMAT_U24_BE:
return 24;
case SNDRV_PCM_FORMAT_S32_LE:
case SNDRV_PCM_FORMAT_S32_BE:
case SNDRV_PCM_FORMAT_U32_LE:
case SNDRV_PCM_FORMAT_U32_BE:
case SNDRV_PCM_FORMAT_FLOAT_LE:
case SNDRV_PCM_FORMAT_FLOAT_BE:
return 32;
case SNDRV_PCM_FORMAT_FLOAT64_LE:
case SNDRV_PCM_FORMAT_FLOAT64_BE:
return 64;
case SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE:
case SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE:
return 24;
case SNDRV_PCM_FORMAT_MU_LAW:
case SNDRV_PCM_FORMAT_A_LAW:
return 8;
case SNDRV_PCM_FORMAT_IMA_ADPCM:
return 4;
default:
return -EINVAL;
}
}
/**
* \brief Return bits needed to store a PCM sample
* \param format Sample format
* \return bits per sample, a negative error code if not applicable
*/
int snd_pcm_format_physical_width(snd_pcm_format_t format)
{
switch (format) {
case SNDRV_PCM_FORMAT_S8:
case SNDRV_PCM_FORMAT_U8:
return 8;
case SNDRV_PCM_FORMAT_S16_LE:
case SNDRV_PCM_FORMAT_S16_BE:
case SNDRV_PCM_FORMAT_U16_LE:
case SNDRV_PCM_FORMAT_U16_BE:
return 16;
case SNDRV_PCM_FORMAT_S24_LE:
case SNDRV_PCM_FORMAT_S24_BE:
case SNDRV_PCM_FORMAT_U24_LE:
case SNDRV_PCM_FORMAT_U24_BE:
case SNDRV_PCM_FORMAT_S32_LE:
case SNDRV_PCM_FORMAT_S32_BE:
case SNDRV_PCM_FORMAT_U32_LE:
case SNDRV_PCM_FORMAT_U32_BE:
case SNDRV_PCM_FORMAT_FLOAT_LE:
case SNDRV_PCM_FORMAT_FLOAT_BE:
case SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE:
case SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE:
return 32;
case SNDRV_PCM_FORMAT_FLOAT64_LE:
case SNDRV_PCM_FORMAT_FLOAT64_BE:
return 64;
case SNDRV_PCM_FORMAT_MU_LAW:
case SNDRV_PCM_FORMAT_A_LAW:
return 8;
case SNDRV_PCM_FORMAT_IMA_ADPCM:
return 4;
default:
return -EINVAL;
}
}
/**
* \brief Return bytes needed to store a quantity of PCM sample
* \param format Sample format
* \param samples Samples count
* \return bytes needed, a negative error code if not integer or unknown
*/
ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples)
{
switch (format) {
case SNDRV_PCM_FORMAT_S8:
case SNDRV_PCM_FORMAT_U8:
return samples;
case SNDRV_PCM_FORMAT_S16_LE:
case SNDRV_PCM_FORMAT_S16_BE:
case SNDRV_PCM_FORMAT_U16_LE:
case SNDRV_PCM_FORMAT_U16_BE:
return samples * 2;
case SNDRV_PCM_FORMAT_S24_LE:
case SNDRV_PCM_FORMAT_S24_BE:
case SNDRV_PCM_FORMAT_U24_LE:
case SNDRV_PCM_FORMAT_U24_BE:
case SNDRV_PCM_FORMAT_S32_LE:
case SNDRV_PCM_FORMAT_S32_BE:
case SNDRV_PCM_FORMAT_U32_LE:
case SNDRV_PCM_FORMAT_U32_BE:
case SNDRV_PCM_FORMAT_FLOAT_LE:
case SNDRV_PCM_FORMAT_FLOAT_BE:
return samples * 4;
case SNDRV_PCM_FORMAT_FLOAT64_LE:
case SNDRV_PCM_FORMAT_FLOAT64_BE:
return samples * 8;
case SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE:
case SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE:
return samples * 4;
case SNDRV_PCM_FORMAT_MU_LAW:
case SNDRV_PCM_FORMAT_A_LAW:
return samples;
case SNDRV_PCM_FORMAT_IMA_ADPCM:
if (samples & 1)
return -EINVAL;
return samples / 2;
default:
assert(0);
return -EINVAL;
}
}
/**
* \brief Return 64 bit expressing silence for a PCM sample format
* \param format Sample format
* \return silence 64 bit word
*/
u_int64_t snd_pcm_format_silence_64(snd_pcm_format_t format)
{
switch (format) {
case SNDRV_PCM_FORMAT_S8:
case SNDRV_PCM_FORMAT_S16_LE:
case SNDRV_PCM_FORMAT_S16_BE:
case SNDRV_PCM_FORMAT_S24_LE:
case SNDRV_PCM_FORMAT_S24_BE:
case SNDRV_PCM_FORMAT_S32_LE:
case SNDRV_PCM_FORMAT_S32_BE:
return 0;
case SNDRV_PCM_FORMAT_U8:
return 0x8080808080808080ULL;
#ifdef SNDRV_LITTLE_ENDIAN
case SNDRV_PCM_FORMAT_U16_LE:
return 0x8000800080008000ULL;
case SNDRV_PCM_FORMAT_U24_LE:
return 0x0080000000800000ULL;
case SNDRV_PCM_FORMAT_U32_LE:
return 0x8000000080000000ULL;
case SNDRV_PCM_FORMAT_U16_BE:
return 0x0080008000800080ULL;
case SNDRV_PCM_FORMAT_U24_BE:
return 0x0000800000008000ULL;
case SNDRV_PCM_FORMAT_U32_BE:
return 0x0000008000000080ULL;
#else
case SNDRV_PCM_FORMAT_U16_LE:
return 0x0080008000800080ULL;
case SNDRV_PCM_FORMAT_U24_LE:
return 0x0000800000008000ULL;
case SNDRV_PCM_FORMAT_U32_LE:
return 0x0000008000000080ULL;
case SNDRV_PCM_FORMAT_U16_BE:
return 0x8000800080008000ULL;
case SNDRV_PCM_FORMAT_U24_BE:
return 0x0080000000800000ULL;
case SNDRV_PCM_FORMAT_U32_BE:
return 0x8000000080000000ULL;
#endif
case SNDRV_PCM_FORMAT_FLOAT_LE:
{
union {
float f;
u_int32_t i;
} u;
u.f = 0.0;
#ifdef SNDRV_LITTLE_ENDIAN
return u.i;
#else
return bswap_32(u.i);
#endif
}
case SNDRV_PCM_FORMAT_FLOAT64_LE:
{
union {
double f;
u_int64_t i;
} u;
u.f = 0.0;
#ifdef SNDRV_LITTLE_ENDIAN
return u.i;
#else
return bswap_64(u.i);
#endif
}
case SNDRV_PCM_FORMAT_FLOAT_BE:
{
union {
float f;
u_int32_t i;
} u;
u.f = 0.0;
#ifdef SNDRV_LITTLE_ENDIAN
return bswap_32(u.i);
#else
return u.i;
#endif
}
case SNDRV_PCM_FORMAT_FLOAT64_BE:
{
union {
double f;
u_int64_t i;
} u;
u.f = 0.0;
#ifdef SNDRV_LITTLE_ENDIAN
return bswap_64(u.i);
#else
return u.i;
#endif
}
case SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE:
case SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE:
return 0;
case SNDRV_PCM_FORMAT_MU_LAW:
return 0x7f7f7f7f7f7f7f7fULL;
case SNDRV_PCM_FORMAT_A_LAW:
return 0x5555555555555555ULL;
case SNDRV_PCM_FORMAT_IMA_ADPCM: /* special case */
case SNDRV_PCM_FORMAT_MPEG:
case SNDRV_PCM_FORMAT_GSM:
case SNDRV_PCM_FORMAT_SPECIAL:
return 0;
default:
assert(0);
return 0;
}
return 0;
}
/**
* \brief Return 32 bit expressing silence for a PCM sample format
* \param format Sample format
* \return silence 32 bit word
*/
u_int32_t snd_pcm_format_silence_32(snd_pcm_format_t format)
{
assert(snd_pcm_format_physical_width(format) <= 32);
return (u_int32_t)snd_pcm_format_silence_64(format);
}
/**
* \brief Return 16 bit expressing silence for a PCM sample format
* \param format Sample format
* \return silence 16 bit word
*/
u_int16_t snd_pcm_format_silence_16(snd_pcm_format_t format)
{
assert(snd_pcm_format_physical_width(format) <= 16);
return (u_int16_t)snd_pcm_format_silence_64(format);
}
/**
* \brief Return 8 bit expressing silence for a PCM sample format
* \param format Sample format
* \return silence 8 bit word
*/
u_int8_t snd_pcm_format_silence(snd_pcm_format_t format)
{
assert(snd_pcm_format_physical_width(format) <= 8);
return (u_int8_t)snd_pcm_format_silence_64(format);
}
/**
* \brief Silence a PCM samples buffer
* \param format Sample format
* \param data Buffer
* \return samples Samples count
*/
int snd_pcm_format_set_silence(snd_pcm_format_t format, void *data, unsigned int samples)
{
if (samples == 0)
return 0;
switch (snd_pcm_format_physical_width(format)) {
case 4: {
u_int8_t silence = snd_pcm_format_silence_64(format);
unsigned int samples1;
if (samples % 2 != 0)
return -EINVAL;
samples1 = samples / 2;
memset(data, silence, samples1);
break;
}
case 8: {
u_int8_t silence = snd_pcm_format_silence_64(format);
memset(data, silence, samples);
break;
}
case 16: {
u_int16_t silence = snd_pcm_format_silence_64(format);
while (samples-- > 0)
*((u_int16_t *)data)++ = silence;
break;
}
case 32: {
u_int32_t silence = snd_pcm_format_silence_64(format);
while (samples-- > 0)
*((u_int32_t *)data)++ = silence;
break;
}
case 64: {
u_int64_t silence = snd_pcm_format_silence_64(format);
while (samples-- > 0)
*((u_int64_t *)data)++ = silence;
break;
}
default:
assert(0);
return -EINVAL;
}
return 0;
}
static int linear_formats[4*2*2] = {
SNDRV_PCM_FORMAT_S8,
SNDRV_PCM_FORMAT_S8,
SNDRV_PCM_FORMAT_U8,
SNDRV_PCM_FORMAT_U8,
SNDRV_PCM_FORMAT_S16_LE,
SNDRV_PCM_FORMAT_S16_BE,
SNDRV_PCM_FORMAT_U16_LE,
SNDRV_PCM_FORMAT_U16_BE,
SNDRV_PCM_FORMAT_S24_LE,
SNDRV_PCM_FORMAT_S24_BE,
SNDRV_PCM_FORMAT_U24_LE,
SNDRV_PCM_FORMAT_U24_BE,
SNDRV_PCM_FORMAT_S32_LE,
SNDRV_PCM_FORMAT_S32_BE,
SNDRV_PCM_FORMAT_U32_LE,
SNDRV_PCM_FORMAT_U32_BE
};
/**
* \brief Compose a PCM sample linear format
* \param width Nominal bits per sample
* \param unsignd Sign: 0 signed, 1 unsigned
* \return big_endian Endian: 0 little endian, 1 big endian
*/
snd_pcm_format_t snd_pcm_build_linear_format(int width, int unsignd, int big_endian)
{
switch (width) {
case 8:
width = 0;
break;
case 16:
width = 1;
break;
case 24:
width = 2;
break;
case 32:
width = 3;
break;
default:
return SND_PCM_FORMAT_UNKNOWN;
}
return ((int(*)[2][2])linear_formats)[width][!!unsignd][!!big_endian];
}
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