dwd.c

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/*
** Copyright (C) 2002-2004 Erik de Castro Lopo <[e-mail]>
**
** 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.
*/

#include	<stdio.h>
#include	<fcntl.h>
#include	<string.h>
#include	<ctype.h>

#include	"sndfile.h"
#include	"config.h"
#include	"sfendian.h"
#include	"common.h"

#if (ENABLE_EXPERIMENTAL_CODE == 0)

int
dwd_open	(SF_PRIVATE *psf)
{	if (psf)
		return SFE_UNIMPLEMENTED ;
	return (psf && 0) ;
} /* dwd_open */

#else

/*------------------------------------------------------------------------------
** Macros to handle big/little endian issues.
*/

#define SFE_DWD_NO_DWD			1666
#define SFE_DWD_BAND_BIT_WIDTH 	1667
#define SFE_DWD_COMPRESSION		1668

#define	DWD_IDENTIFIER		"DiamondWare Digitized\n\0\x1a"
#define	DWD_IDENTIFIER_LEN	24

#define	DWD_HEADER_LEN		57

/*------------------------------------------------------------------------------
** Typedefs.
*/

/*------------------------------------------------------------------------------
** Private static functions.
*/

static int	dwd_read_header (SF_PRIVATE *psf) ;

static int	dwd_close		(SF_PRIVATE *psf) ;

/*------------------------------------------------------------------------------
** Public function.
*/

int
dwd_open (SF_PRIVATE *psf)
{	int	subformat, error = 0 ;

	if (psf->mode == SFM_READ || (psf->mode == SFM_RDWR && psf->filelength > 0))
	{	if ((error = dwd_read_header (psf)))
			return error ;
		} ;

	if ((psf->sf.format & SF_FORMAT_TYPEMASK) != SF_FORMAT_DWD)
		return	SFE_BAD_OPEN_FORMAT ;

	subformat = psf->sf.format & SF_FORMAT_SUBMASK ;

	if (psf->mode == SFM_WRITE || psf->mode == SFM_RDWR)
	{
		/*-psf->endian = psf->sf.format & SF_FORMAT_ENDMASK ;
		if (CPU_IS_LITTLE_ENDIAN && psf->endian == SF_ENDIAN_CPU)
			psf->endian = SF_ENDIAN_LITTLE ;
		else if (psf->endian != SF_ENDIAN_LITTLE)
			psf->endian = SF_ENDIAN_BIG ;

		if (! (encoding = dwd_write_header (psf, SF_FALSE)))
			return psf->error ;

		psf->write_header = dwd_write_header ;
		-*/
		} ;

	psf->close = dwd_close ;

	/*-psf->blockwidth = psf->bytewidth * psf->sf.channels ;-*/

	return error ;
} /* dwd_open */

/*------------------------------------------------------------------------------
*/

static int
dwd_close	(SF_PRIVATE *psf)
{
	psf = psf ;

	return 0 ;
} /* dwd_close */

/* This struct contains all the fields of interest om the DWD header, but does not
** do so in the same order and layout as the actual file, header.
** No assumptions are made about the packing of this struct.
*/
typedef struct
{	unsigned char major, minor, compression, channels, bitwidth ;
	unsigned short srate, maxval ;
	unsigned int id, datalen, frames, offset ;
} DWD_HEADER ;

static int
dwd_read_header (SF_PRIVATE *psf)
{	DWD_HEADER	dwdh ;

	memset (psf->u.cbuf, 0, sizeof (psf->u.cbuf)) ;
	/* Set position to start of file to begin reading header. */
	psf_binheader_readf (psf, "pb", 0, psf->u.cbuf, DWD_IDENTIFIER_LEN) ;

	if (memcmp (psf->u.cbuf, DWD_IDENTIFIER, DWD_IDENTIFIER_LEN) != 0)
		return SFE_DWD_NO_DWD ;

	psf_log_printf (psf, "Read only : DiamondWare Digitized (.dwd)\n", psf->u.cbuf) ;

	psf_binheader_readf (psf, "11", &dwdh.major, &dwdh.minor) ;
	psf_binheader_readf (psf, "e4j1", &dwdh.id, 1, &dwdh.compression) ;
	psf_binheader_readf (psf, "e211", &dwdh.srate, &dwdh.channels, &dwdh.bitwidth) ;
	psf_binheader_readf (psf, "e24", &dwdh.maxval, &dwdh.datalen) ;
	psf_binheader_readf (psf, "e44", &dwdh.frames, &dwdh.offset) ;

	psf_log_printf (psf, "  Version Major : %d\n  Version Minor : %d\n  Unique ID     : %08X\n",
						dwdh.major, dwdh.minor, dwdh.id) ;
	psf_log_printf (psf, "  Compression   : %d => ", dwdh.compression) ;

	if (dwdh.compression != 0)
	{	psf_log_printf (psf, "Unsupported compression\n") ;
		return SFE_DWD_COMPRESSION ;
		}
	else
		psf_log_printf (psf, "None\n") ;

	psf_log_printf (psf, "  Sample Rate   : %d\n  Channels      : %d\n"
						 "  Bit Width     : %d\n",
						 dwdh.srate, dwdh.channels, dwdh.bitwidth) ;

	switch (dwdh.bitwidth)
	{	case 8 :
				psf->sf.format = SF_FORMAT_DWD | SF_FORMAT_PCM_S8 ;
				psf->bytewidth = 1 ;
				break ;

		case 16 :
				psf->sf.format = SF_FORMAT_DWD | SF_FORMAT_PCM_16 ;
				psf->bytewidth = 2 ;
				break ;

		default :
				psf_log_printf (psf, "*** Bad bit width %d\n", dwdh.bitwidth) ;
				return SFE_DWD_BAND_BIT_WIDTH ;
				} ;

	if (psf->filelength != dwdh.offset + dwdh.datalen)
	{	psf_log_printf (psf, "  Data Length   : %d (should be %D)\n", dwdh.datalen, psf->filelength - dwdh.offset) ;
		dwdh.datalen = (unsigned int) (psf->filelength - dwdh.offset) ;
		}
	else
		psf_log_printf (psf, "  Data Length   : %d\n", dwdh.datalen) ;

	psf_log_printf (psf, "  Max Value     : %d\n", dwdh.maxval) ;
	psf_log_printf (psf, "  Frames        : %d\n", dwdh.frames) ;
	psf_log_printf (psf, "  Data Offset   : %d\n", dwdh.offset) ;

	psf->datalength = dwdh.datalen ;
	psf->dataoffset = dwdh.offset ;

	psf->endian = SF_ENDIAN_LITTLE ;

	psf->sf.samplerate = dwdh.srate ;
	psf->sf.channels = dwdh.channels ;
	psf->sf.sections = 1 ;

	return pcm_init (psf) ;
} /* dwd_read_header */

/*------------------------------------------------------------------------------
*/

#endif
/*
** 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: a5e1d2a6-a840-4039-a0e7-e1a43eb05a4f
*/