xi.c

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	normfact = (psf->norm_double == SF_TRUE) ? (1.0 * 0x7F) : 1.0 ;

	bufferlen = ARRAY_LEN (psf->u.ucbuf) ;

	while (len > 0)
	{	if (len < bufferlen)
			bufferlen = (int) len ;
		d2dsc_array (pxi, ptr + total, psf->u.scbuf, bufferlen, normfact) ;
		writecount = psf_fwrite (psf->u.scbuf, sizeof (signed char), bufferlen, psf) ;
		total += writecount ;
		if (writecount < bufferlen)
			break ;
		len -= writecount ;
		} ;

	return total ;
} /* dpcm_write_d2dsc */


static sf_count_t
dpcm_write_s2dles (SF_PRIVATE *psf, short *ptr, sf_count_t len)
{	XI_PRIVATE	*pxi ;
	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

	if ((pxi = psf->fdata) == NULL)
		return 0 ;

	bufferlen = ARRAY_LEN (psf->u.sbuf) ;

	while (len > 0)
	{	if (len < bufferlen)
			bufferlen = (int) len ;
		s2dles_array (pxi, ptr + total, psf->u.sbuf, bufferlen) ;
		writecount = psf_fwrite (psf->u.sbuf, sizeof (short), bufferlen, psf) ;
		total += writecount ;
		if (writecount < bufferlen)
			break ;
		len -= writecount ;
		} ;

	return total ;
} /* dpcm_write_s2dles */

static sf_count_t
dpcm_write_i2dles (SF_PRIVATE *psf, int *ptr, sf_count_t len)
{	XI_PRIVATE	*pxi ;
	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

	if ((pxi = psf->fdata) == NULL)
		return 0 ;

	bufferlen = ARRAY_LEN (psf->u.sbuf) ;

	while (len > 0)
	{	if (len < bufferlen)
			bufferlen = (int) len ;
		i2dles_array (pxi, ptr + total, psf->u.sbuf, bufferlen) ;
		writecount = psf_fwrite (psf->u.sbuf, sizeof (short), bufferlen, psf) ;
		total += writecount ;
		if (writecount < bufferlen)
			break ;
		len -= writecount ;
		} ;

	return total ;
} /* dpcm_write_i2dles */

static sf_count_t
dpcm_write_f2dles (SF_PRIVATE *psf, float *ptr, sf_count_t len)
{	XI_PRIVATE	*pxi ;
	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;
	float		normfact ;

	if ((pxi = psf->fdata) == NULL)
		return 0 ;

	normfact = (psf->norm_float == SF_TRUE) ? (1.0 * 0x7FFF) : 1.0 ;

	bufferlen = ARRAY_LEN (psf->u.sbuf) ;

	while (len > 0)
	{	if (len < bufferlen)
			bufferlen = (int) len ;
		f2dles_array (pxi, ptr + total, psf->u.sbuf, bufferlen, normfact) ;
		writecount = psf_fwrite (psf->u.sbuf, sizeof (short), bufferlen, psf) ;
		total += writecount ;
		if (writecount < bufferlen)
			break ;
		len -= writecount ;
		} ;

	return total ;
} /* dpcm_write_f2dles */

static sf_count_t
dpcm_write_d2dles (SF_PRIVATE *psf, double *ptr, sf_count_t len)
{	XI_PRIVATE	*pxi ;
	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;
	double		normfact ;

	if ((pxi = psf->fdata) == NULL)
		return 0 ;

	normfact = (psf->norm_double == SF_TRUE) ? (1.0 * 0x7FFF) : 1.0 ;

	bufferlen = ARRAY_LEN (psf->u.sbuf) ;

	while (len > 0)
	{	if (len < bufferlen)
			bufferlen = (int) len ;
		d2dles_array (pxi, ptr + total, psf->u.sbuf, bufferlen, normfact) ;
		writecount = psf_fwrite (psf->u.sbuf, sizeof (short), bufferlen, psf) ;
		total += writecount ;
		if (writecount < bufferlen)
			break ;
		len -= writecount ;
		} ;

	return total ;
} /* dpcm_write_d2dles */


/*==============================================================================
*/

static void
dsc2s_array (XI_PRIVATE *pxi, signed char *src, int count, short *dest)
{	signed char	last_val ;
	int			k ;

	last_val = pxi->last_16 >> 8 ;

	for (k = 0 ; k < count ; k++)
	{	last_val += src [k] ;
		dest [k] = last_val << 8 ;
		} ;

	pxi->last_16 = last_val << 8 ;
} /* dsc2s_array */

static void
dsc2i_array (XI_PRIVATE *pxi, signed char *src, int count, int *dest)
{	signed char	last_val ;
	int			k ;

	last_val = pxi->last_16 >> 8 ;

	for (k = 0 ; k < count ; k++)
	{	last_val += src [k] ;
		dest [k] = last_val << 24 ;
		} ;

	pxi->last_16 = last_val << 8 ;
} /* dsc2i_array */

static void
dsc2f_array (XI_PRIVATE *pxi, signed char *src, int count, float *dest, float normfact)
{	signed char	last_val ;
	int			k ;

	last_val = pxi->last_16 >> 8 ;

	for (k = 0 ; k < count ; k++)
	{	last_val += src [k] ;
		dest [k] = last_val * normfact ;
		} ;

	pxi->last_16 = last_val << 8 ;
} /* dsc2f_array */

static void
dsc2d_array (XI_PRIVATE *pxi, signed char *src, int count, double *dest, double normfact)
{	signed char	last_val ;
	int			k ;

	last_val = pxi->last_16 >> 8 ;

	for (k = 0 ; k < count ; k++)
	{	last_val += src [k] ;
		dest [k] = last_val * normfact ;
		} ;

	pxi->last_16 = last_val << 8 ;
} /* dsc2d_array */

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

static void
s2dsc_array (XI_PRIVATE *pxi, short *src, signed char *dest, int count)
{	signed char	last_val, current ;
	int			k ;

	last_val = pxi->last_16 >> 8 ;

	for (k = 0 ; k < count ; k++)
	{	current = src [k] >> 8 ;
		dest [k] = current - last_val ;
		last_val = current ;
		} ;

	pxi->last_16 = last_val << 8 ;
} /* s2dsc_array */

static void
i2dsc_array (XI_PRIVATE *pxi, int *src, signed char *dest, int count)
{	signed char	last_val, current ;
	int			k ;

	last_val = pxi->last_16 >> 8 ;

	for (k = 0 ; k < count ; k++)
	{	current = src [k] >> 24 ;
		dest [k] = current - last_val ;
		last_val = current ;
		} ;

	pxi->last_16 = last_val << 8 ;
} /* i2dsc_array */

static void
f2dsc_array (XI_PRIVATE *pxi, float *src, signed char *dest, int count, float normfact)
{	signed char	last_val, current ;
	int			k ;

	last_val = pxi->last_16 >> 8 ;

	for (k = 0 ; k < count ; k++)
	{	current = lrintf (src [k] * normfact) ;
		dest [k] = current - last_val ;
		last_val = current ;
		} ;

	pxi->last_16 = last_val << 8 ;
} /* f2dsc_array */

static void
d2dsc_array (XI_PRIVATE *pxi, double *src, signed char *dest, int count, double normfact)
{	signed char	last_val, current ;
	int			k ;

	last_val = pxi->last_16 >> 8 ;

	for (k = 0 ; k < count ; k++)
	{	current = lrint (src [k] * normfact) ;
		dest [k] = current - last_val ;
		last_val = current ;
		} ;

	pxi->last_16 = last_val << 8 ;
} /* d2dsc_array */

/*==============================================================================
*/

static void
dles2s_array (XI_PRIVATE *pxi, short *src, int count, short *dest)
{	short	last_val ;
	int		k ;

	last_val = pxi->last_16 ;

	for (k = 0 ; k < count ; k++)
	{	last_val += LES2H_SHORT (src [k]) ;
		dest [k] = last_val ;
		} ;

	pxi->last_16 = last_val ;
} /* dles2s_array */

static void
dles2i_array (XI_PRIVATE *pxi, short *src, int count, int *dest)
{	short	last_val ;
	int		k ;

	last_val = pxi->last_16 ;

	for (k = 0 ; k < count ; k++)
	{	last_val += LES2H_SHORT (src [k]) ;
		dest [k] = last_val << 16 ;
		} ;

	pxi->last_16 = last_val ;
} /* dles2i_array */

static void
dles2f_array (XI_PRIVATE *pxi, short *src, int count, float *dest, float normfact)
{	short	last_val ;
	int		k ;

	last_val = pxi->last_16 ;

	for (k = 0 ; k < count ; k++)
	{	last_val += LES2H_SHORT (src [k]) ;
		dest [k] = last_val * normfact ;
		} ;

	pxi->last_16 = last_val ;
} /* dles2f_array */

static void
dles2d_array (XI_PRIVATE *pxi, short *src, int count, double *dest, double normfact)
{	short	last_val ;
	int		k ;

	last_val = pxi->last_16 ;

	for (k = 0 ; k < count ; k++)
	{	last_val += LES2H_SHORT (src [k]) ;
		dest [k] = last_val * normfact ;
		} ;

	pxi->last_16 = last_val ;
} /* dles2d_array */

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

static void
s2dles_array (XI_PRIVATE *pxi, short *src, short *dest, int count)
{	short	diff, last_val ;
	int		k ;

	last_val = pxi->last_16 ;

	for (k = 0 ; k < count ; k++)
	{	diff = src [k] - last_val ;
		dest [k] = LES2H_SHORT (diff) ;
		last_val = src [k] ;
		} ;

	pxi->last_16 = last_val ;
} /* s2dles_array */

static void
i2dles_array (XI_PRIVATE *pxi, int *src, short *dest, int count)
{	short	diff, last_val ;
	int		k ;

	last_val = pxi->last_16 ;

	for (k = 0 ; k < count ; k++)
	{	diff = (src [k] >> 16) - last_val ;
		dest [k] = LES2H_SHORT (diff) ;
		last_val = src [k] >> 16 ;
		} ;

	pxi->last_16 = last_val ;
} /* i2dles_array */

static void
f2dles_array (XI_PRIVATE *pxi, float *src, short *dest, int count, float normfact)
{	short	diff, last_val, current ;
	int		k ;

	last_val = pxi->last_16 ;

	for (k = 0 ; k < count ; k++)
	{	current = lrintf (src [k] * normfact) ;
		diff = current - last_val ;
		dest [k] = LES2H_SHORT (diff) ;
		last_val = current ;
		} ;

	pxi->last_16 = last_val ;
} /* f2dles_array */

static void
d2dles_array (XI_PRIVATE *pxi, double *src, short *dest, int count, double normfact)
{	short	diff, last_val, current ;
	int		k ;

	last_val = pxi->last_16 ;

	for (k = 0 ; k < count ; k++)
	{	current = lrint (src [k] * normfact) ;
		diff = current - last_val ;
		dest [k] = LES2H_SHORT (diff) ;
		last_val = current ;
		} ;

	pxi->last_16 = last_val ;
} /* d2dles_array */

/*
** 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: 1ab2dbe0-29af-4d80-9c6f-cb21b67521bc
*/