ref: 356439161f99dafc9e2b36ce23abbc6833708ea4
dir: /src/au.c/
/* libSoX Sun format with header (SunOS 4.1; see /usr/demo/SOUND).
* Copyright 1991, 1992, 1993 Guido van Rossum And Sundry Contributors.
*
* This source code is freely redistributable and may be used for
* any purpose. This copyright notice must be maintained.
* Guido van Rossum And Sundry Contributors are not responsible for
* the consequences of using this software.
*
* October 7, 1998 - cbagwell@sprynet.com
* G.723 was using incorrect # of bits. Corrected to 3 and 5 bits.
*
* NeXT uses this format also, but has more format codes defined.
* DEC uses a slight variation and swaps bytes.
* We support only the common formats, plus
* CCITT G.721 (32 kbit/s) and G.723 (24/40 kbit/s),
* courtesy of Sun's public domain implementation.
*/
#include "sox_i.h"
#include "g72x.h"
#include <string.h>
/* Magic numbers used in Sun and NeXT audio files */
static struct {char str[4]; sox_bool reverse_bytes; char const * desc;} id[] = {
{"\x2e\x73\x6e\x64", MACHINE_IS_LITTLEENDIAN, "big-endian `.snd'"},
{"\x64\x6e\x73\x2e", MACHINE_IS_BIGENDIAN , "little-endian `.snd'"},
{"\x00\x64\x73\x2e", MACHINE_IS_BIGENDIAN , "little-endian `\\0ds.' (for DEC)"},
{"\x2e\x73\x64\x00", MACHINE_IS_LITTLEENDIAN, "big-endian `\\0ds.'"},
{" ", 0, NULL}
};
#define FIXED_HDR 24
#define SUN_UNSPEC ~0u /* Unspecified data size (this is legal) */
typedef enum {
Unspecified, Mulaw_8, Linear_8, Linear_16, Linear_24, Linear_32, Float,
Double, Indirect, Nested, Dsp_core, Dsp_data_8, Dsp_data_16, Dsp_data_24,
Dsp_data_32, Unknown, Display, Mulaw_squelch, Emphasized, Compressed,
Compressed_emphasized, Dsp_commands, Dsp_commands_samples, Adpcm_g721,
Adpcm_g722, Adpcm_g723_3, Adpcm_g723_5, Alaw_8, Unknown_other} ft_encoding_t;
static char const * const str[] = {
"Unspecified", "8-bit mu-law", "8-bit signed linear", "16-bit signed linear",
"24-bit signed linear", "32-bit signed linear", "Floating-point",
"Double precision float", "Fragmented sampled data", "Unknown", "DSP program",
"8-bit fixed-point", "16-bit fixed-point", "24-bit fixed-point",
"32-bit fixed-point", "Unknown", "Non-audio data", "Mu-law squelch",
"16-bit linear with emphasis", "16-bit linear with compression",
"16-bit linear with emphasis and compression", "Music Kit DSP commands",
"Music Kit DSP samples", "4-bit G.721 ADPCM", "G.722 ADPCM",
"3-bit G.723 ADPCM", "5-bit G.723 ADPCM", "8-bit a-law", "Unknown"};
static ft_encoding_t ft_enc(unsigned size, sox_encoding_t encoding)
{
if (encoding == SOX_ENCODING_ULAW && size == 8) return Mulaw_8;
if (encoding == SOX_ENCODING_ALAW && size == 8) return Alaw_8;
if (encoding == SOX_ENCODING_SIGN2 && size == 8) return Linear_8;
if (encoding == SOX_ENCODING_SIGN2 && size == 16) return Linear_16;
if (encoding == SOX_ENCODING_SIGN2 && size == 24) return Linear_24;
if (encoding == SOX_ENCODING_SIGN2 && size == 32) return Linear_32;
if (encoding == SOX_ENCODING_FLOAT && size == 32) return Float;
if (encoding == SOX_ENCODING_FLOAT && size == 64) return Double;
return Unspecified;
}
static sox_encoding_t sox_enc(uint32_t ft_encoding, unsigned * size)
{
switch (ft_encoding) {
case Mulaw_8 : *size = 8; return SOX_ENCODING_ULAW;
case Alaw_8 : *size = 8; return SOX_ENCODING_ALAW;
case Linear_8 : *size = 8; return SOX_ENCODING_SIGN2;
case Linear_16 : *size = 16; return SOX_ENCODING_SIGN2;
case Linear_24 : *size = 24; return SOX_ENCODING_SIGN2;
case Linear_32 : *size = 32; return SOX_ENCODING_SIGN2;
case Float : *size = 32; return SOX_ENCODING_FLOAT;
case Double : *size = 64; return SOX_ENCODING_FLOAT;
case Adpcm_g721 : *size = 4; return SOX_ENCODING_G721; /* read-only */
case Adpcm_g723_3: *size = 3; return SOX_ENCODING_G723; /* read-only */
case Adpcm_g723_5: *size = 5; return SOX_ENCODING_G723; /* read-only */
default: return SOX_ENCODING_UNKNOWN;
}
}
typedef struct { /* For G72x decoding: */
struct g72x_state state;
int (*dec_routine)(int i, int out_coding, struct g72x_state *state_ptr);
unsigned int in_buffer;
int in_bits;
} priv_t;
/*
* Unpack input codes and pass them back as bytes.
* Returns 1 if there is residual input, returns -1 if eof, else returns 0.
* (Adapted from Sun's decode.c.)
*/
static int unpack_input(sox_format_t * ft, unsigned char *code)
{
priv_t * p = (priv_t *) ft->priv;
unsigned char in_byte;
if (p->in_bits < (int)ft->encoding.bits_per_sample) {
if (lsx_read_b_buf(ft, &in_byte, (size_t) 1) != 1) {
*code = 0;
return -1;
}
p->in_buffer |= (in_byte << p->in_bits);
p->in_bits += 8;
}
*code = p->in_buffer & ((1 << ft->encoding.bits_per_sample) - 1);
p->in_buffer >>= ft->encoding.bits_per_sample;
p->in_bits -= ft->encoding.bits_per_sample;
return p->in_bits > 0;
}
static size_t dec_read(sox_format_t *ft, sox_sample_t *buf, size_t samp)
{
priv_t * p = (priv_t *)ft->priv;
unsigned char code;
size_t done;
for (done = 0; samp > 0 && unpack_input(ft, &code) >= 0; ++done, --samp)
*buf++ = SOX_SIGNED_16BIT_TO_SAMPLE(
(*p->dec_routine)(code, AUDIO_ENCODING_LINEAR, &p->state),);
return done;
}
static int startread(sox_format_t * ft)
{
priv_t * p = (priv_t *) ft->priv;
char magic[4]; /* These 6 variables represent a Sun sound */
uint32_t hdr_size; /* header on disk. The uint32_t are written as */
uint32_t data_size; /* big-endians. At least extra bytes (totalling */
uint32_t ft_encoding; /* hdr_size - FIXED_HDR) are an "info" field of */
uint32_t rate; /* unspecified nature, usually a string. By */
uint32_t channels; /* convention the header size is a multiple of 4. */
unsigned i, bits_per_sample;
sox_encoding_t encoding;
if (lsx_readchars(ft, magic, sizeof(magic)))
return SOX_EOF;
for (i = 0; id[i].desc && memcmp(magic, id[i].str, sizeof(magic)); ++i);
if (!id[i].desc) {
lsx_fail_errno(ft, SOX_EHDR, "au: can't find Sun/NeXT/DEC identifier");
return SOX_EOF;
}
lsx_report("found %s identifier", id[i].desc);
ft->encoding.reverse_bytes = id[i].reverse_bytes;
if (lsx_readdw(ft, &hdr_size) ||
lsx_readdw(ft, &data_size) || /* Can be SUN_UNSPEC */
lsx_readdw(ft, &ft_encoding) ||
lsx_readdw(ft, &rate) ||
lsx_readdw(ft, &channels))
return SOX_EOF;
if (hdr_size < FIXED_HDR) {
lsx_fail_errno(ft, SOX_EHDR, "header size %u is too small", hdr_size);
return SOX_EOF;
}
if (hdr_size < FIXED_HDR + 4)
lsx_warn("header size %u is too small", hdr_size);
if (!(encoding = sox_enc(ft_encoding, &bits_per_sample))) {
int n = min(ft_encoding, Unknown_other);
lsx_fail_errno(ft, SOX_EFMT, "unsupported encoding `%s' (%#x)", str[n], ft_encoding);
return SOX_EOF;
}
switch (ft_encoding) {
case Adpcm_g721 : p->dec_routine = g721_decoder ; break;
case Adpcm_g723_3: p->dec_routine = g723_24_decoder; break;
case Adpcm_g723_5: p->dec_routine = g723_40_decoder; break;
}
if (p->dec_routine) {
g72x_init_state(&p->state);
ft->handler.seek = NULL;
ft->handler.read = dec_read;
}
if (hdr_size > FIXED_HDR) {
size_t info_size = hdr_size - FIXED_HDR;
char * buf = lsx_calloc(1, info_size + 1); /* +1 ensures null-terminated */
if (lsx_readchars(ft, buf, info_size) != SOX_SUCCESS) {
free(buf);
return SOX_EOF;
}
sox_append_comments(&ft->oob.comments, buf);
free(buf);
}
if (data_size == SUN_UNSPEC)
data_size = SOX_UNSPEC;
return lsx_check_read_params(ft, channels, (sox_rate_t)rate, encoding,
bits_per_sample, div_bits(data_size, bits_per_sample), sox_true);
}
static int write_header(sox_format_t * ft)
{
char * comment = lsx_cat_comments(ft->oob.comments);
size_t len = strlen(comment) + 1; /* Write out null-terminated */
size_t info_len = max(4, (len + 3) & ~3u); /* Minimum & multiple of 4 bytes */
size_t size = ft->olength? ft->olength : ft->signal.length;
int i = ft->encoding.reverse_bytes == MACHINE_IS_BIGENDIAN? 2 : 0;
sox_bool error = sox_false
||lsx_writechars(ft, id[i].str, sizeof(id[i].str))
||lsx_writedw(ft, FIXED_HDR + (unsigned)info_len)
||lsx_writedw(ft, (unsigned) (size != SOX_UNSPEC? size*(ft->encoding.bits_per_sample >> 3) : SUN_UNSPEC))
||lsx_writedw(ft, ft_enc(ft->encoding.bits_per_sample, ft->encoding.encoding))
||lsx_writedw(ft, (unsigned)(ft->signal.rate + .5))
||lsx_writedw(ft, ft->signal.channels)
||lsx_writechars(ft, comment, len)
||lsx_padbytes(ft, info_len - len);
free(comment);
return error? SOX_EOF: SOX_SUCCESS;
}
LSX_FORMAT_HANDLER(au)
{
static char const * const names[] = {"au", "snd", NULL};
static unsigned const write_encodings[] = {
SOX_ENCODING_ULAW, 8, 0,
SOX_ENCODING_ALAW, 8, 0,
SOX_ENCODING_SIGN2, 8, 16, 24, 32, 0,
SOX_ENCODING_FLOAT, 32, 64, 0,
0};
static sox_format_handler_t const handler = {SOX_LIB_VERSION_CODE,
"PCM file format used widely on Sun systems",
names, SOX_FILE_BIG_END | SOX_FILE_REWIND,
startread, lsx_rawread, NULL,
write_header, lsx_rawwrite, NULL,
lsx_rawseek, write_encodings, NULL, sizeof(priv_t)
};
return &handler;
}