voc.c

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	*/

	if (subformat == SF_FORMAT_PCM_U8 && psf->sf.channels == 1)
	{	/* 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)
	{	/* 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.frames * 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.frames * 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.frames * 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.frames * 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) ;

	if (psf->error)
		return psf->error ;

	psf->dataoffset = psf->headindex ;

	if (current > 0)
		psf_fseek (psf, current, SEEK_SET) ;

	return psf->error ;
} /* 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, 0, SEEK_END) ;

		/* Write terminator */
		psf_fwrite (&byte, 1, 1, psf) ;

		voc_write_header (psf, SF_TRUE) ;
		} ;

	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.frames = 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: [e-mail]

(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 <[e-mail]>.
--------------------------------------------------------------------------
Creative Voice (VOC) file format
--------------------------------

From: [e-mail]

(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

------------------------------------------------------------------------*/
/*
** Do not edit or modify anything in this comment block.
** The arch-tag line is a file identity tag for the GNU Arch 
** revision control system.
**
** arch-tag: 40a50167-a81c-463a-9e1d-3282ff84e09d
*/