pcm.c

Audacity是一款用於錄音和編輯聲音的、免費的開放源碼軟體。它可以執行於Mac OS X、Microsoft Windows、GNU/Linux和其它作業系統

	else

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

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

	return total ;
} /* pcm_write_s2bes */

static sf_count_t
pcm_write_s2les	(SF_PRIVATE *psf, short *ptr, sf_count_t len)
{	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

	if (CPU_IS_LITTLE_ENDIAN)
		return psf_fwrite (ptr, sizeof (short), len, psf) ;

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

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

	return total ;
} /* pcm_write_s2les */

static sf_count_t
pcm_write_s2bet	(SF_PRIVATE *psf, short *ptr, sf_count_t len)
{	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

	bufferlen = sizeof (psf->u.ucbuf) / SIZEOF_TRIBYTE ;

	while (len > 0)
	{	if (len < bufferlen)
			bufferlen = (int) len ;
		s2bet_array (ptr + total, (tribyte*) (psf->u.ucbuf), bufferlen) ;
		writecount = psf_fwrite (psf->u.ucbuf, SIZEOF_TRIBYTE, bufferlen, psf) ;
		total += writecount ;
		if (writecount < bufferlen)
			break ;
		len -= writecount ;
		} ;

	return total ;
} /* pcm_write_s2bet */

static sf_count_t
pcm_write_s2let	(SF_PRIVATE *psf, short *ptr, sf_count_t len)
{	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

	bufferlen = sizeof (psf->u.ucbuf) / SIZEOF_TRIBYTE ;

	while (len > 0)
	{	if (len < bufferlen)
			bufferlen = (int) len ;
		s2let_array (ptr + total, (tribyte*) (psf->u.ucbuf), bufferlen) ;
		writecount = psf_fwrite (psf->u.ucbuf, SIZEOF_TRIBYTE, bufferlen, psf) ;
		total += writecount ;
		if (writecount < bufferlen)
			break ;
		len -= writecount ;
		} ;

	return total ;
} /* pcm_write_s2let */

static sf_count_t
pcm_write_s2bei	(SF_PRIVATE *psf, short *ptr, sf_count_t len)
{	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

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

	while (len > 0)
	{	if (len < bufferlen)
			bufferlen = (int) len ;
		s2bei_array (ptr + total, psf->u.ibuf, bufferlen) ;
		writecount = psf_fwrite (psf->u.ibuf, sizeof (int), bufferlen, psf) ;
		total += writecount ;
		if (writecount < bufferlen)
			break ;
		len -= writecount ;
		} ;

	return total ;
} /* pcm_write_s2bei */

static sf_count_t
pcm_write_s2lei	(SF_PRIVATE *psf, short *ptr, sf_count_t len)
{	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

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

	while (len > 0)
	{	if (len < bufferlen)
			bufferlen = (int) len ;
		s2lei_array (ptr + total, psf->u.ibuf, bufferlen) ;
		writecount = psf_fwrite (psf->u.ibuf, sizeof (int), bufferlen, psf) ;
		total += writecount ;
		if (writecount < bufferlen)
			break ;
		len -= writecount ;
		} ;

	return total ;
} /* pcm_write_s2lei */

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

static sf_count_t
pcm_write_i2sc	(SF_PRIVATE *psf, int *ptr, sf_count_t len)
{	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

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

	while (len > 0)
	{	if (len < bufferlen)
			bufferlen = (int) len ;
		i2sc_array (ptr + total, psf->u.scbuf, bufferlen) ;
		writecount = psf_fwrite (psf->u.scbuf, sizeof (signed char), bufferlen, psf) ;
		total += writecount ;
		if (writecount < bufferlen)
			break ;
		len -= writecount ;
		} ;

	return total ;
} /* pcm_write_i2sc */

static sf_count_t
pcm_write_i2uc	(SF_PRIVATE *psf, int *ptr, sf_count_t len)
{	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

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

	while (len > 0)
	{	if (len < bufferlen)
			bufferlen = (int) len ;
		i2uc_array (ptr + total, psf->u.ucbuf, bufferlen) ;
		writecount = psf_fwrite (psf->u.ucbuf, sizeof (signed char), bufferlen, psf) ;
		total += writecount ;
		if (writecount < bufferlen)
			break ;
		len -= writecount ;
		} ;

	return total ;
} /* pcm_write_i2uc */

static sf_count_t
pcm_write_i2bes	(SF_PRIVATE *psf, int *ptr, sf_count_t len)
{	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

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

	while (len > 0)
	{	if (len < bufferlen)
			bufferlen = (int) len ;
		i2bes_array (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 ;
} /* pcm_write_i2bes */

static sf_count_t
pcm_write_i2les	(SF_PRIVATE *psf, int *ptr, sf_count_t len)
{	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

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

	while (len > 0)
	{	if (len < bufferlen)
			bufferlen = (int) len ;
		i2les_array (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 ;
} /* pcm_write_i2les */

static sf_count_t
pcm_write_i2bet	(SF_PRIVATE *psf, int *ptr, sf_count_t len)
{	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

	bufferlen = sizeof (psf->u.ucbuf) / SIZEOF_TRIBYTE ;

	while (len > 0)
	{	if (len < bufferlen)
			bufferlen = (int) len ;
		i2bet_array (ptr + total, (tribyte*) (psf->u.ucbuf), bufferlen) ;
		writecount = psf_fwrite (psf->u.ucbuf, SIZEOF_TRIBYTE, bufferlen, psf) ;
		total += writecount ;
		if (writecount < bufferlen)
			break ;
		len -= writecount ;
		} ;

	return total ;
} /* pcm_write_i2bet */

static sf_count_t
pcm_write_i2let	(SF_PRIVATE *psf, int *ptr, sf_count_t len)
{	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

	bufferlen = sizeof (psf->u.ucbuf) / SIZEOF_TRIBYTE ;

	while (len > 0)
	{	if (len < bufferlen)
			bufferlen = (int) len ;
		i2let_array (ptr + total, (tribyte*) (psf->u.ucbuf), bufferlen) ;
		writecount = psf_fwrite (psf->u.ucbuf, SIZEOF_TRIBYTE, bufferlen, psf) ;
		total += writecount ;
		if (writecount < bufferlen)
			break ;
		len -= writecount ;
		} ;

	return total ;
} /* pcm_write_i2les */

static sf_count_t
pcm_write_i2bei	(SF_PRIVATE *psf, int *ptr, sf_count_t len)
{	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

	if (CPU_IS_BIG_ENDIAN)
		return psf_fwrite (ptr, sizeof (int), len, psf) ;

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

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

	return total ;
} /* pcm_write_i2bei */

static sf_count_t
pcm_write_i2lei	(SF_PRIVATE *psf, int *ptr, sf_count_t len)
{	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

	if (CPU_IS_LITTLE_ENDIAN)
		return psf_fwrite (ptr, sizeof (int), len, psf) ;

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

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

	return total ;
} /* pcm_write_i2lei */

/*------------------------------------------------------------------------------
**==============================================================================
**------------------------------------------------------------------------------
*/

static void
f2sc_array (float *src, signed char *dest, int count, int normalize)
{	float normfact ;

	normfact = normalize ? (1.0 * 0x7F) : 1.0 ;

	while (--count >= 0)
	{	dest [count] = lrintf (src [count] * normfact) ;
		} ;
} /* f2sc_array */

static void
f2sc_clip_array (float *src, signed char *dest, int count, int normalize)
{	float	normfact, scaled_value ;

	normfact = normalize ? (8.0 * 0x10000000) : (1.0 * 0x1000000) ;

	while (--count >= 0)
	{	scaled_value = src [count] * normfact ;
		if (CPU_CLIPS_POSITIVE == 0 && scaled_value >= (1.0 * 0x7FFFFFFF))
		{	dest [count] = 127 ;
			continue ;
			} ;
		if (CPU_CLIPS_NEGATIVE == 0 && scaled_value <= (-8.0 * 0x10000000))
		{	dest [count] = -128 ;
			continue ;
			} ;

		dest [count] = lrintf (scaled_value) >> 24 ;
		} ;
} /* f2sc_clip_array */

static sf_count_t
pcm_write_f2sc	(SF_PRIVATE *psf, float *ptr, sf_count_t len)
{	void		(*convert) (float *, signed char *, int, int) ;
	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

	convert = (psf->add_clipping) ? f2sc_clip_array : f2sc_array ;
	bufferlen = ARRAY_LEN (psf->u.scbuf) ;

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

	return total ;
} /* pcm_write_f2sc */

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

static	void
f2uc_array	(float *src, unsigned char *dest, int count, int normalize)
{	float normfact ;

	normfact = normalize ? (1.0 * 0x7F) : 1.0 ;

	while (--count >= 0)
	{	dest [count] = lrintf (src [count] * normfact) + 128 ;
		} ;
} /* f2uc_array */

static	void
f2uc_clip_array	(float *src, unsigned char *dest, int count, int normalize)
{	float	normfact, scaled_value ;

	normfact = normalize ? (8.0 * 0x10000000) : (1.0 * 0x1000000) ;

	while (--count >= 0)
	{	scaled_value = src [count] * normfact ;
		if (CPU_CLIPS_POSITIVE == 0 && scaled_value >= (1.0 * 0x7FFFFFFF))
		{	dest [count] = 0xFF ;
			continue ;
			} ;
		if (CPU_CLIPS_NEGATIVE == 0 && scaled_value <= (-8.0 * 0x10000000))
		{	dest [count] = 0 ;
			continue ;
			} ;

		dest [count] = (lrintf (scaled_value) >> 24) + 128 ;
		} ;
} /* f2uc_clip_array */

static sf_count_t
pcm_write_f2uc	(SF_PRIVATE *psf, float *ptr, sf_count_t len)
{	void		(*convert) (float *, unsigned char *, int, int) ;
	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

	convert = (psf->add_clipping) ? f2uc_clip_array : f2uc_array ;
	bufferlen = ARRAY_LEN (psf->u.ucbuf) ;

	while (len > 0)
	{	if (len < bufferlen)
			bufferlen = (int) len ;
		convert (ptr + total, psf->u.ucbuf, bufferlen, psf->norm_float) ;
		writecount = psf_fwrite (psf->u.ucbuf, sizeof (unsigned char), bufferlen, psf) ;
		total += writecount ;
		if (writecount < bufferlen)
			break ;
		len -= writecount ;
		} ;

	return total ;
} /* pcm_write_f2uc */

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

static void
f2bes_array (float *src, short *dest, int count, int normalize)
{	unsigned char	*ucptr ;
	float 			normfact ;
	short			value ;

	normfact = normalize ? (1.0 * 0x7FFF) : 1.0 ;
	ucptr = ((unsigned char*) dest) + 2 * count ;

	while (--count >= 0)
	{	ucptr -= 2 ;
		value = lrintf (src [count] * normfact) ;
		ucptr [1] = value ;
		ucptr [0] = value >> 8 ;
			} ;
} /* f2bes_array */

static void
f2bes_clip_array (float *src, short *dest, int count, int normalize)
{	unsigned char	*ucptr ;
	float			normfact, scaled_value ;
	int				value ;

	normfact = normalize ? (8.0 * 0x10000000) : (1.0 * 0x10000) ;
	ucptr = ((unsigned char*) dest) + 2 * count ;

	while (--count >= 0)
	{	ucptr -= 2 ;
		scaled_value = src [count] * normfact ;
		if (CPU_CLIPS_POSITIVE == 0 && scaled_value >= (1.0 * 0x7FFFFFFF))
		{	ucptr [1] = 0xFF ;
			ucptr [0] = 0x7F ;
			continue ;
		} ;
		if (CPU_CLIPS_NEGATIVE == 0 && scaled_value <= (-8.0 * 0x10000000))
		{	ucptr [1] = 0x00 ;
			ucptr [0] = 0x80 ;
			continue ;
			} ;

		value = lrintf (scaled_value) ;
		ucptr [1] = value >> 16 ;
		ucptr [0] = value >> 24 ;
		} ;
} /* f2bes_clip_array */

static sf_count_t
pcm_write_f2bes	(SF_PRIVATE *psf, float *ptr, sf_count_t len)
{	void		(*convert) (float *, short *t, int, int) ;
	int			bufferlen, writecount ;
	sf_count_t	total = 0 ;

	convert = (psf->add_clipping) ? f2bes_clip_array : f2bes_array ;
	bufferlen = ARRAY_LEN (psf->u.sbuf) ;

	while (len > 0)
	{	if (len < bufferlen)