ref: 7af9c20656f528fe2329d91197d4f83094d7715a
dir: /common/libsndfile/src/voc.c/
/*
** Copyright (C) 2001-2002 Erik de Castro Lopo <[email protected]>
**
** This program 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 program; if not, write to the Free Software
** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/* RANT:
** The VOC file format is the most brain damaged format I have yet had to deal
** with. No one programmer could have bee stupid enough to put this together.
** Instead it looks like a series of manic, dyslexic assembly language programmers
** hacked it to fit their needs.
** Utterly woeful.
*/
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include "sndfile.h"
#include "config.h"
#include "sfendian.h"
#include "common.h"
/*------------------------------------------------------------------------------
* Typedefs for file chunks.
*/
#define VOC_MAX_SECTIONS 200
enum
{ VOC_TERMINATOR = 0,
VOC_SOUND_DATA = 1,
VOC_SOUND_CONTINUE = 2,
VOC_SILENCE = 3,
VOC_MARKER = 4,
VOC_ASCII = 5,
VOC_REPEAT = 6,
VOC_END_REPEAT = 7,
VOC_EXTENDED = 8,
VOC_EXTENDED_II = 9
} ;
typedef struct
{ int samples ;
int offset ; /* Offset of zero => silence. */
} SND_DATA_BLOCKS ;
typedef struct
{ unsigned int sections, section_types ;
int samplerate, channels, bitwidth ;
SND_DATA_BLOCKS blocks [VOC_MAX_SECTIONS] ;
} VOC_DATA ;
/*------------------------------------------------------------------------------
* Private static functions.
*/
static int voc_close (SF_PRIVATE *psf) ;
static int voc_write_header (SF_PRIVATE *psf) ;
static int voc_read_header (SF_PRIVATE *psf) ;
static const char* voc_encoding2str (int encoding) ;
#if 0
/* These functions would be required for files with more than one VOC_SOUND_DATA
** segment. Not sure whether to bother implementing this.
*/
static int voc_multi_init (SF_PRIVATE *psf, VOC_DATA *pvoc) ;
static int voc_multi_read_uc2s (SF_PRIVATE *psf, short *ptr, int len) ;
static int voc_multi_read_les2s (SF_PRIVATE *psf, short *ptr, int len) ;
static int voc_multi_read_uc2i (SF_PRIVATE *psf, int *ptr, int len) ;
static int voc_multi_read_les2i (SF_PRIVATE *psf, int *ptr, int len) ;
static int voc_multi_read_uc2f (SF_PRIVATE *psf, float *ptr, int len) ;
static int voc_multi_read_les2f (SF_PRIVATE *psf, float *ptr, int len) ;
static int voc_multi_read_uc2d (SF_PRIVATE *psf, double *ptr, int len) ;
static int voc_multi_read_les2d (SF_PRIVATE *psf, double *ptr, int len) ;
#endif
/*------------------------------------------------------------------------------
** Public function.
*/
int
voc_open (SF_PRIVATE *psf)
{ int subformat, error = 0 ;
if (psf->mode == SFM_READ || (psf->mode == SFM_RDWR && psf->filelength > 0))
{ if ((error = voc_read_header (psf)))
return error ;
} ;
subformat = psf->sf.format & SF_FORMAT_SUBMASK ;
if (psf->mode == SFM_WRITE || psf->mode == SFM_RDWR)
{ if ((psf->sf.format & SF_FORMAT_TYPEMASK) != SF_FORMAT_VOC)
return SFE_BAD_OPEN_FORMAT ;
psf->endian = SF_ENDIAN_LITTLE ;
if ((error = voc_write_header (psf)))
return error ;
psf->write_header = voc_write_header ;
} ;
psf->blockwidth = psf->bytewidth * psf->sf.channels ;
psf->close = voc_close ;
switch (subformat)
{ case SF_FORMAT_PCM_U8 :
case SF_FORMAT_PCM_16 :
error = pcm_init (psf) ;
break ;
case SF_FORMAT_ALAW :
error = alaw_init (psf) ;
break ;
case SF_FORMAT_ULAW :
error = ulaw_init (psf) ;
break ;
default : return SFE_UNIMPLEMENTED ;
} ;
return error ;
} /* voc_open */
/*------------------------------------------------------------------------------
*/
static int
voc_read_header (SF_PRIVATE *psf)
{ VOC_DATA *pvoc ;
char creative [20] ;
unsigned char block_type, rate_byte ;
short version, checksum, encoding, dataoffset ;
int offset ;
/* Set position to start of file to begin reading header. */
offset = psf_binheader_readf (psf, "pb", 0, creative, sizeof (creative)) ;
if (creative [sizeof (creative) - 1] != 0x1A)
return SFE_VOC_NO_CREATIVE ;
/* Terminate the string. */
creative [sizeof (creative) - 1] = 0 ;
if (strcmp ("Creative Voice File", creative))
return SFE_VOC_NO_CREATIVE ;
psf_log_printf (psf, "%s\n", creative) ;
offset += psf_binheader_readf (psf, "e222", &dataoffset, &version, &checksum) ;
psf->dataoffset = dataoffset ;
psf_log_printf (psf, "dataoffset : %d\n"
"version : 0x%X\n"
"checksum : 0x%X\n", psf->dataoffset, version, checksum) ;
if (version != 0x010A && version != 0x0114)
return SFE_VOC_BAD_VERSION ;
if (! (psf->fdata = malloc (sizeof (VOC_DATA))))
return SFE_MALLOC_FAILED ;
pvoc = (VOC_DATA*) psf->fdata ;
memset (pvoc, 0, sizeof (VOC_DATA)) ;
/* Set the default encoding now. */
psf->sf.format = SF_FORMAT_VOC ; /* Major format */
encoding = SF_FORMAT_PCM_U8 ; /* Minor format */
psf->endian = SF_ENDIAN_LITTLE ;
while (1)
{ offset += psf_binheader_readf (psf, "1", &block_type) ;
switch (block_type)
{ case VOC_ASCII :
{ int size ;
offset += psf_binheader_readf (psf, "e3", &size) ;
psf_log_printf (psf, " ASCII : %d\n", size) ;
offset += psf_binheader_readf (psf, "b", psf->header, size) ;
psf->header [size] = 0 ;
psf_log_printf (psf, " text : %s\n", psf->header) ;
} ;
continue ;
case VOC_SOUND_DATA :
case VOC_EXTENDED :
case VOC_EXTENDED_II :
break ;
default : psf_log_printf (psf, "*** Weird block marker (%d)\n", block_type) ;
} ;
break ;
} ;
if (block_type == VOC_SOUND_DATA)
{ unsigned char compression ;
int size ;
offset += psf_binheader_readf (psf, "e311", &size, &rate_byte, &compression) ;
psf->sf.samplerate = 1000000 / (256 - (rate_byte & 0xFF)) ;
psf_log_printf (psf, " Sound Data : %d\n"
" sr : %d => %dHz\n"
" comp : %d\n",
size, rate_byte, psf->sf.samplerate, compression) ;
if (offset + size - 1 > psf->filelength)
{ psf_log_printf (psf, "Seems to be a truncated file.\n") ;
puts ("Seems to be a truncated file.\n") ;
psf_log_printf (psf, "offset : %d size : %d filelength : %d\n", offset, size, psf->filelength) ;
return SFE_VOC_BAD_SECTIONS ;
}
else if (offset + size - 1 < psf->filelength)
{ psf_log_printf (psf, "Seems to be a multi-segment file.\n") ;
psf_log_printf (psf, "offset : %d size : %d filelength : %d\n", offset, size, psf->filelength) ;
return SFE_VOC_BAD_SECTIONS ;
} ;
psf->dataoffset = offset ;
psf->dataend = psf->filelength - 1 ;
psf->sf.channels = 1 ;
psf->bytewidth = 1 ;
psf->sf.format = SF_FORMAT_VOC | SF_FORMAT_PCM_U8 ;
psf->chars = SF_CHARS_UNSIGNED ;
return 0 ;
} ;
if (block_type == VOC_EXTENDED)
{ unsigned char pack, stereo, compression ;
unsigned short rate_short ;
int size ;
offset += psf_binheader_readf (psf, "e3211", &size, &rate_short, &pack, &stereo) ;
psf_log_printf (psf, " Extended : %d\n", size) ;
if (size == 4)
psf_log_printf (psf, " size : 4\n") ;
else
psf_log_printf (psf, " size : %d (should be 4)\n", size) ;
psf_log_printf (psf, " pack : %d\n"
" stereo : %s\n", pack, (stereo ? "yes" : "no")) ;
if (stereo)
{ psf->sf.channels = 2 ;
psf->sf.samplerate = 128000000 / (65536 - rate_short) ;
}
else
{ psf->sf.channels = 1 ;
psf->sf.samplerate = 256000000 / (65536 - rate_short) ;
} ;
psf_log_printf (psf, " sr : %d => %dHz\n", (rate_short & 0xFFFF), psf->sf.samplerate) ;
offset += psf_binheader_readf (psf, "1", &block_type) ;
if (block_type != VOC_SOUND_DATA)
{ psf_log_printf (psf, "*** Expecting VOC_SOUND_DATA section.\n") ;
return SFE_VOC_BAD_FORMAT ;
} ;
offset += psf_binheader_readf (psf, "e311", &size, &rate_byte, &compression) ;
psf_log_printf (psf, " Sound Data : %d\n"
" sr : %d\n"
" comp : %d\n", size, rate_byte, compression) ;
if (offset + size - 1 > psf->filelength)
{ psf_log_printf (psf, "Seems to be a truncated file.\n") ;
puts ("Seems to be a truncated file.\n") ;
/*-printf ("offset : %d size : %d filelength : %ld\n", offset, size, psf->filelength) ;-*/
return SFE_VOC_BAD_SECTIONS ;
}
else if (offset + size - 1 < psf->filelength)
{ /*-printf ("offset : %d size : %d filelength : %ld\n", offset, size, psf->filelength) ;-*/
psf_log_printf (psf, "Seems to be a multi-segment file.\n") ;
return SFE_VOC_BAD_SECTIONS ;
} ;
psf->dataoffset = offset ;
psf->dataend = psf->filelength - 1 ;
psf->bytewidth = 1 ;
psf->sf.format = SF_FORMAT_VOC | SF_FORMAT_PCM_U8 ;
psf->chars = SF_CHARS_UNSIGNED ;
return 0 ;
}
if (block_type == VOC_EXTENDED_II)
{ unsigned char bitwidth, channels ;
int size, fourbytes ;
offset += psf_binheader_readf (psf, "e341124", &size, &psf->sf.samplerate,
&bitwidth, &channels, &encoding, &fourbytes) ;
if (size * 2 == psf->filelength - 39)
{ int temp_size = psf->filelength - 31 ;
psf_log_printf (psf, " Extended II : %d (SoX bug: should be %d)\n", size, temp_size) ;
size = temp_size ;
}
else
psf_log_printf (psf, " Extended II : %d\n", size) ;
psf_log_printf (psf, " sample rate : %d\n"
" bit width : %d\n"
" channels : %d\n", psf->sf.samplerate, bitwidth, channels) ;
if (bitwidth == 16 && encoding == 0)
{ encoding = 4 ;
psf_log_printf (psf, " encoding : 0 (SoX bug: should be 4 for 16 bit signed PCM)\n") ;
}
else
psf_log_printf (psf, " encoding : %d => %s\n", encoding, voc_encoding2str (encoding)) ;
psf_log_printf (psf, " fourbytes : %X\n", fourbytes) ;
psf->sf.channels = channels ;
psf->dataoffset = offset ;
psf->dataend = psf->filelength - 1 ;
if (size + 31 > psf->filelength)
{ psf_log_printf (psf, "Seems to be a truncated file.\n") ;
size = psf->filelength - 31 ;
}
else if (size + 31 < psf->filelength)
psf_log_printf (psf, "Seems to be a multi-segment file.\n") ;
switch (encoding)
{ case 0 :
psf->sf.format = SF_FORMAT_VOC | SF_FORMAT_PCM_U8 ;
psf->bytewidth = 1 ;
break ;
case 4 :
psf->sf.format = SF_FORMAT_VOC | SF_FORMAT_PCM_16 ;
psf->bytewidth = 2 ;
break ;
case 6 :
psf->sf.format = SF_FORMAT_VOC | SF_FORMAT_ALAW ;
psf->bytewidth = 1 ;
break ;
case 7 :
psf->sf.format = SF_FORMAT_VOC | SF_FORMAT_ULAW ;
psf->bytewidth = 1 ;
break ;
default : /* Unknown */
return SFE_UNKNOWN_FORMAT ;
break ;
} ;
} ;
return 0 ;
} /* voc_read_header */
/*====================================================================================
*/
static int
voc_write_header (SF_PRIVATE *psf)
{ int rate_const, subformat ;
subformat = psf->sf.format & SF_FORMAT_SUBMASK ;
/* Reset the current header length to zero. */
psf->header [0] = 0 ;
psf->headindex = 0 ;
psf_fseek (psf->filedes, 0, SEEK_SET) ;
/* VOC marker and 0x1A byte. */
psf_binheader_writef (psf, "eb1", "Creative Voice File", 19, 0x1A) ;
/* Data offset, version and other. */
psf_binheader_writef (psf, "e222", 26, 0x0114, 0x111F) ;
/* Use same logic as SOX.
** If the file is mono 8 bit data, use VOC_SOUND_DATA.
** If the file is mono 16 bit data, use VOC_EXTENED.
** Otherwise use VOC_EXTENED_2.
*/
if (subformat == SF_FORMAT_PCM_U8 && psf->sf.channels == 1)
{ psf->chars = SF_CHARS_UNSIGNED ;
/* samplerate = 1000000 / (256 - rate_const) ; */
rate_const = 256 - 1000000 / psf->sf.samplerate ;
/* First type marker, length, rate_const and compression */
psf_binheader_writef (psf, "e1311", VOC_SOUND_DATA, (int) (psf->datalength + 1), rate_const, 0) ;
}
else if (subformat == SF_FORMAT_PCM_U8 && psf->sf.channels == 2)
{ psf->chars = SF_CHARS_UNSIGNED ;
/* sample_rate = 128000000 / (65536 - rate_short) ; */
rate_const = 65536 - 128000000 / psf->sf.samplerate ;
/* First write the VOC_EXTENDED section
** marker, length, rate_const and compression
*/
psf_binheader_writef (psf, "e13211", VOC_EXTENDED, 4, rate_const, 0, 1) ;
/* samplerate = 1000000 / (256 - rate_const) ; */
rate_const = 256 - 1000000 / psf->sf.samplerate ;
/* Now write the VOC_SOUND_DATA section
** marker, length, rate_const and compression
*/
psf_binheader_writef (psf, "e1311", VOC_SOUND_DATA, (int) (psf->datalength + 1), rate_const, 0) ;
}
else
{ int length ;
if (psf->sf.channels < 1 || psf->sf.channels > 2)
return SFE_CHANNEL_COUNT ;
switch (subformat)
{ case SF_FORMAT_PCM_U8 :
psf->bytewidth = 1 ;
length = psf->sf.samples * psf->sf.channels * psf->bytewidth + 12 ;
/* Marker, length, sample rate, bitwidth, stereo flag, encoding and fourt zero bytes. */
psf_binheader_writef (psf, "e1341124", VOC_EXTENDED_II, length, psf->sf.samplerate, 16, psf->sf.channels, 4, 0) ;
break ;
case SF_FORMAT_PCM_16 :
psf->bytewidth = 2 ;
length = psf->sf.samples * psf->sf.channels * psf->bytewidth + 12;
/* Marker, length, sample rate, bitwidth, stereo flag, encoding and fourt zero bytes. */
psf_binheader_writef (psf, "e1341124", VOC_EXTENDED_II, length, psf->sf.samplerate, 16, psf->sf.channels, 4, 0) ;
break ;
case SF_FORMAT_ALAW :
psf->bytewidth = 1 ;
length = psf->sf.samples * psf->sf.channels * psf->bytewidth + 12;
psf_binheader_writef (psf, "e1341124", VOC_EXTENDED_II, length, psf->sf.samplerate, 8, psf->sf.channels, 6, 0) ;
break ;
case SF_FORMAT_ULAW :
psf->bytewidth = 1 ;
length = psf->sf.samples * psf->sf.channels * psf->bytewidth + 12 ;
psf_binheader_writef (psf, "e1341124", VOC_EXTENDED_II, length, psf->sf.samplerate, 8, psf->sf.channels, 7, 0) ;
break ;
default : return SFE_UNIMPLEMENTED ;
} ;
} ;
psf_fwrite (psf->header, psf->headindex, 1, psf->filedes) ;
psf->dataoffset = psf->headindex ;
return 0 ;
} /* voc_write_header */
static int
voc_close (SF_PRIVATE *psf)
{
if (psf->mode == SFM_WRITE || psf->mode == SFM_RDWR)
{ /* Now we know for certain the length of the file we can re-write
** correct values for the FORM, 8SVX and BODY chunks.
*/
unsigned byte = VOC_TERMINATOR ;
psf_fseek (psf->filedes, 0, SEEK_END) ;
/* Write terminator */
psf_fwrite (&byte, 1, 1, psf->filedes) ;
psf->filelength = psf_ftell (psf->filedes) ;
psf_fseek (psf->filedes, 0, SEEK_SET) ;
psf->datalength = psf->filelength - psf->dataoffset ;
psf->sf.samples = psf->datalength / (psf->bytewidth * psf->sf.channels) ;
voc_write_header (psf) ;
} ;
return 0 ;
} /* voc_close */
static const char*
voc_encoding2str (int encoding)
{
switch (encoding)
{ case 0 : return "8 bit unsigned PCM" ;
case 4 : return "16 bit signed PCM" ;
case 6 : return "A-law" ;
case 7 : return "u-law" ;
default : break ;
}
return "*** Unknown ***" ;
} /* voc_encoding2str */
/*====================================================================================
*/
#if 0
static int
voc_multi_init (SF_PRIVATE *psf, VOC_DATA *pvoc)
{
psf->sf.samples = 0 ;
if (pvoc->bitwidth == 8)
{ psf->read_short = voc_multi_read_uc2s ;
psf->read_int = voc_multi_read_uc2i ;
psf->read_float = voc_multi_read_uc2f ;
psf->read_double = voc_multi_read_uc2d ;
return 0 ;
} ;
if (pvoc->bitwidth == 16)
{ psf->read_short = voc_multi_read_les2s ;
psf->read_int = voc_multi_read_les2i ;
psf->read_float = voc_multi_read_les2f ;
psf->read_double = voc_multi_read_les2d ;
return 0 ;
} ;
psf_log_printf (psf, "Error : bitwith != 8 && bitwidth != 16.\n") ;
return SFE_UNIMPLEMENTED ;
} /* voc_multi_read_int */
/*------------------------------------------------------------------------------------
*/
static int
voc_multi_read_uc2s (SF_PRIVATE *psf, short *ptr, int len)
{
return 0 ;
} /* voc_multi_read_uc2s */
static int
voc_multi_read_les2s (SF_PRIVATE *psf, short *ptr, int len)
{
return 0 ;
} /* voc_multi_read_les2s */
static int
voc_multi_read_uc2i (SF_PRIVATE *psf, int *ptr, int len)
{
return 0 ;
} /* voc_multi_read_uc2i */
static int
voc_multi_read_les2i (SF_PRIVATE *psf, int *ptr, int len)
{
return 0 ;
} /* voc_multi_read_les2i */
static int
voc_multi_read_uc2f (SF_PRIVATE *psf, float *ptr, int len)
{
return 0 ;
} /* voc_multi_read_uc2f */
static int
voc_multi_read_les2f (SF_PRIVATE *psf, float *ptr, int len)
{
return 0 ;
} /* voc_multi_read_les2f */
static int
voc_multi_read_uc2d (SF_PRIVATE *psf, double *ptr, int len)
{
return 0 ;
} /* voc_multi_read_uc2d */
static int
voc_multi_read_les2d (SF_PRIVATE *psf, double *ptr, int len)
{
return 0 ;
} /* voc_multi_read_les2d */
#endif
/*------------------------------------------------------------------------------------
Creative Voice (VOC) file format
--------------------------------
~From: [email protected]
(byte numbers are hex!)
HEADER (bytes 00-19)
Series of DATA BLOCKS (bytes 1A+) [Must end w/ Terminator Block]
- ---------------------------------------------------------------
HEADER:
=======
byte # Description
------ ------------------------------------------
00-12 "Creative Voice File"
13 1A (eof to abort printing of file)
14-15 Offset of first datablock in .voc file (std 1A 00
in Intel Notation)
16-17 Version number (minor,major) (VOC-HDR puts 0A 01)
18-19 1's Comp of Ver. # + 1234h (VOC-HDR puts 29 11)
- ---------------------------------------------------------------
DATA BLOCK:
===========
Data Block: TYPE(1-byte), SIZE(3-bytes), INFO(0+ bytes)
NOTE: Terminator Block is an exception -- it has only the TYPE byte.
TYPE Description Size (3-byte int) Info
---- ----------- ----------------- -----------------------
00 Terminator (NONE) (NONE)
01 Sound data 2+length of data *
02 Sound continue length of data Voice Data
03 Silence 3 **
04 Marker 2 Marker# (2 bytes)
05 ASCII length of string null terminated string
06 Repeat 2 Count# (2 bytes)
07 End repeat 0 (NONE)
08 Extended 4 ***
*Sound Info Format:
---------------------
00 Sample Rate
01 Compression Type
02+ Voice Data
**Silence Info Format:
----------------------------
00-01 Length of silence - 1
02 Sample Rate
***Extended Info Format:
---------------------
00-01 Time Constant: Mono: 65536 - (256000000/sample_rate)
Stereo: 65536 - (25600000/(2*sample_rate))
02 Pack
03 Mode: 0 = mono
1 = stereo
Marker# -- Driver keeps the most recent marker in a status byte
Count# -- Number of repetitions + 1
Count# may be 1 to FFFE for 0 - FFFD repetitions
or FFFF for endless repetitions
Sample Rate -- SR byte = 256-(1000000/sample_rate)
Length of silence -- in units of sampling cycle
Compression Type -- of voice data
8-bits = 0
4-bits = 1
2.6-bits = 2
2-bits = 3
Multi DAC = 3+(# of channels) [interesting--
this isn't in the developer's manual]
---------------------------------------------------------------------------------
Addendum submitted by Votis Kokavessis:
After some experimenting with .VOC files I found out that there is a Data Block
Type 9, which is not covered in the VOC.TXT file. Here is what I was able to discover
about this block type:
TYPE: 09
SIZE: 12 + length of data
INFO: 12 (twelve) bytes
INFO STRUCTURE:
Bytes 0-1: (Word) Sample Rate (e.g. 44100)
Bytes 2-3: zero (could be that bytes 0-3 are a DWord for Sample Rate)
Byte 4: Sample Size in bits (e.g. 16)
Byte 5: Number of channels (e.g. 1 for mono, 2 for stereo)
Byte 6: Unknown (equal to 4 in all files I examined)
Bytes 7-11: zero
-------------------------------------------------------------------------------------*/
/*=====================================================================================
**=====================================================================================
**=====================================================================================
**=====================================================================================
*/
/*------------------------------------------------------------------------
The following is taken from the Audio File Formats FAQ dated 2-Jan-1995
and submitted by Guido van Rossum <[email protected]>.
--------------------------------------------------------------------------
Creative Voice (VOC) file format
--------------------------------
From: [email protected]
(byte numbers are hex!)
HEADER (bytes 00-19)
Series of DATA BLOCKS (bytes 1A+) [Must end w/ Terminator Block]
- ---------------------------------------------------------------
HEADER:
-------
byte # Description
------ ------------------------------------------
00-12 "Creative Voice File"
13 1A (eof to abort printing of file)
14-15 Offset of first datablock in .voc file (std 1A 00
in Intel Notation)
16-17 Version number (minor,major) (VOC-HDR puts 0A 01)
18-19 2's Comp of Ver. # + 1234h (VOC-HDR puts 29 11)
- ---------------------------------------------------------------
DATA BLOCK:
-----------
Data Block: TYPE(1-byte), SIZE(3-bytes), INFO(0+ bytes)
NOTE: Terminator Block is an exception -- it has only the TYPE byte.
TYPE Description Size (3-byte int) Info
---- ----------- ----------------- -----------------------
00 Terminator (NONE) (NONE)
01 Sound data 2+length of data *
02 Sound continue length of data Voice Data
03 Silence 3 **
04 Marker 2 Marker# (2 bytes)
05 ASCII length of string null terminated string
06 Repeat 2 Count# (2 bytes)
07 End repeat 0 (NONE)
08 Extended 4 ***
*Sound Info Format: **Silence Info Format:
--------------------- ----------------------------
00 Sample Rate 00-01 Length of silence - 1
01 Compression Type 02 Sample Rate
02+ Voice Data
***Extended Info Format:
---------------------
00-01 Time Constant: Mono: 65536 - (256000000/sample_rate)
Stereo: 65536 - (25600000/(2*sample_rate))
02 Pack
03 Mode: 0 = mono
1 = stereo
Marker# -- Driver keeps the most recent marker in a status byte
Count# -- Number of repetitions + 1
Count# may be 1 to FFFE for 0 - FFFD repetitions
or FFFF for endless repetitions
Sample Rate -- SR byte = 256-(1000000/sample_rate)
Length of silence -- in units of sampling cycle
Compression Type -- of voice data
8-bits = 0
4-bits = 1
2.6-bits = 2
2-bits = 3
Multi DAC = 3+(# of channels) [interesting--
this isn't in the developer's manual]
Detailed description of new data blocks (VOC files version 1.20 and above):
(Source is fax from Barry Boone at Creative Labs, 405/742-6622)
BLOCK 8 - digitized sound attribute extension, must preceed block 1.
Used to define stereo, 8 bit audio
BYTE bBlockID; // = 8
BYTE nBlockLen[3]; // 3 byte length
WORD wTimeConstant; // time constant = same as block 1
BYTE bPackMethod; // same as in block 1
BYTE bVoiceMode; // 0-mono, 1-stereo
Data is stored left, right
BLOCK 9 - data block that supersedes blocks 1 and 8.
Used for stereo, 16 bit.
BYTE bBlockID; // = 9
BYTE nBlockLen[3]; // length 12 plus length of sound
DWORD dwSamplesPerSec; // samples per second, not time const.
BYTE bBitsPerSample; // e.g., 8 or 16
BYTE bChannels; // 1 for mono, 2 for stereo
WORD wFormat; // see below
BYTE reserved[4]; // pad to make block w/o data
// have a size of 16 bytes
Valid values of wFormat are:
0x0000 8-bit unsigned PCM
0x0001 Creative 8-bit to 4-bit ADPCM
0x0002 Creative 8-bit to 3-bit ADPCM
0x0003 Creative 8-bit to 2-bit ADPCM
0x0004 16-bit signed PCM
0x0006 CCITT a-Law
0x0007 CCITT u-Law
0x02000 Creative 16-bit to 4-bit ADPCM
Data is stored left, right
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