ref: 7af9c20656f528fe2329d91197d4f83094d7715a
dir: /common/libsndfile/src/ima_adpcm.c/
/*
** Copyright (C) 1999-2002 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.
*/
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include "sndfile.h"
#include "config.h"
#include "sfendian.h"
#include "float_cast.h"
#include "common.h"
typedef struct
{ int channels, blocksize, samplesperblock, blocks ;
int blockcount, samplecount ;
int previous [2] ;
int stepindex [2] ;
unsigned char *block ;
short *samples ;
unsigned char data [4] ; /* Dummy size */
} IMA_ADPCM_PRIVATE ;
/*============================================================================================
** Predefined IMA ADPCM data.
*/
static int ima_index_adjust [16] =
{ -1, -1, -1, -1, /* +0 - +3, decrease the step size */
2, 4, 6, 8, /* +4 - +7, increase the step size */
-1, -1, -1, -1, /* -0 - -3, decrease the step size */
2, 4, 6, 8, /* -4 - -7, increase the step size */
} ;
static int ima_step_size [89] =
{ 7, 8, 9, 10, 11, 12, 13, 14, 16, 17, 19, 21, 23, 25, 28, 31, 34, 37, 41, 45,
50, 55, 60, 66, 73, 80, 88, 97, 107, 118, 130, 143, 157, 173, 190, 209, 230,
253, 279, 307, 337, 371, 408, 449, 494, 544, 598, 658, 724, 796, 876, 963,
1060, 1166, 1282, 1411, 1552, 1707, 1878, 2066, 2272, 2499, 2749, 3024, 3327,
3660, 4026, 4428, 4871, 5358, 5894, 6484, 7132, 7845, 8630, 9493, 10442,
11487, 12635, 13899, 15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794,
32767
} ;
static int ima_reader_init (SF_PRIVATE *psf, int blockalign, int samplesperblock) ;
static int ima_writer_init (SF_PRIVATE *psf, int blockalign) ;
static int ima_decode_block (SF_PRIVATE *psf, IMA_ADPCM_PRIVATE *pima) ;
static int ima_read_block (SF_PRIVATE *psf, IMA_ADPCM_PRIVATE *pima, short *ptr, sf_count_t len) ;
static int ima_encode_block (SF_PRIVATE *psf, IMA_ADPCM_PRIVATE *pima) ;
static int ima_write_block (SF_PRIVATE *psf, IMA_ADPCM_PRIVATE *pima, short *ptr, sf_count_t len) ;
static sf_count_t ima_read_s (SF_PRIVATE *psf, short *ptr, sf_count_t len) ;
static sf_count_t ima_read_i (SF_PRIVATE *psf, int *ptr, sf_count_t len) ;
static sf_count_t ima_read_f (SF_PRIVATE *psf, float *ptr, sf_count_t len) ;
static sf_count_t ima_read_d (SF_PRIVATE *psf, double *ptr, sf_count_t len) ;
static sf_count_t ima_write_s (SF_PRIVATE *psf, short *ptr, sf_count_t len) ;
static sf_count_t ima_write_i (SF_PRIVATE *psf, int *ptr, sf_count_t len) ;
static sf_count_t ima_write_f (SF_PRIVATE *psf, float *ptr, sf_count_t len) ;
static sf_count_t ima_write_d (SF_PRIVATE *psf, double *ptr, sf_count_t len) ;
static sf_count_t ima_seek (SF_PRIVATE *psf, int mode, sf_count_t offset) ;
static int wav_w64_ima_close (SF_PRIVATE *psf) ;
/*-static int aiff_ima_close (SF_PRIVATE *psf) ;-*/
/*============================================================================================
** IMA ADPCM Reader initialisation function.
*/
int
wav_w64_ima_init (SF_PRIVATE *psf, int blockalign, int samplesperblock)
{ int error ;
if (psf->mode == SFM_RDWR)
return SFE_BAD_MODE_RW ;
if (psf->mode == SFM_READ)
if ((error = ima_reader_init (psf, blockalign, samplesperblock)))
return error ;
if (psf->mode == SFM_WRITE)
if ((error = ima_writer_init (psf, blockalign)))
return error ;
psf->new_seek = ima_seek ;
psf->close = wav_w64_ima_close ;
return 0 ;
} /* wav_w64_ima_init */
static int
wav_w64_ima_close (SF_PRIVATE *psf)
{ IMA_ADPCM_PRIVATE *pima ;
if (! psf->fdata)
return 0 ;
pima = (IMA_ADPCM_PRIVATE*) psf->fdata ;
if (psf->mode == SFM_WRITE)
{ /* If a block has been partially assembled, write it out
** as the final block.
*/
if (pima->samplecount && pima->samplecount < pima->samplesperblock)
ima_encode_block (psf, pima) ;
/* Now we know for certain the length of the file we can
** re-write the header.
*/
psf_fseek (psf->filedes, 0, SEEK_END) ;
psf->filelength = psf_ftell (psf->filedes) ;
psf->sf.samples = pima->samplesperblock * pima->blockcount ;
psf->datalength = psf->filelength - psf->dataoffset ;
if (psf->write_header)
psf->write_header (psf) ;
} ;
free (psf->fdata) ;
psf->fdata = NULL ;
return 0 ;
} /* wav_w64_ima_close */
/*-
int
aiff_ima_reader_init (SF_PRIVATE *psf, int blockalign, int samplesperblock)
{ IMA_ADPCM_PUBLIC public ;
public.blocksize = blockalign ;
public.channels = psf->sf.channels ;
public.samplesperblock = samplesperblock ;
return ima_reader_init (psf, &public) ;
} /+* aiff_ima_reader_init *+/
int
aiff_ima_writer_init (SF_PRIVATE *psf, int blocksize)
{ IMA_ADPCM_PUBLIC public ;
int error ;
public.blocksize = blocksize ;
public.channels = psf->sf.channels ;
public.samplesperblock = 2 * (public.blocksize - 4 * psf->sf.channels) / psf->sf.channels + 1 ;
if ((error = ima_writer_init (psf, &public)))
return error ;
if (psf->write_header)
psf->write_header (psf) ;
psf->write_short = ima_write_s ;
psf->write_int = ima_write_i ;
psf->write_float = ima_write_f ;
psf->write_double = ima_write_d ;
psf->new_seek = ima_seek ;
psf->close = aiff_ima_close ;
return 0 ;
} /+* aiff_ima_writer_init *+/
static int
aiff_ima_close (SF_PRIVATE *psf)
{ IMA_ADPCM_PRIVATE *pima ;
if (! psf->fdata)
return 0 ;
pima = (IMA_ADPCM_PRIVATE*) psf->fdata ;
if (psf->mode == SFM_WRITE)
{ /+* If a block has been partially assembled, write it out
** as the final block.
*+/
if (pima->samplecount && pima->samplecount < pima->samplesperblock)
ima_encode_block (psf, pima) ;
/+* Now we know for certain the length of the file we can
** re-write the header.
*+/
psf_fseek (psf->filedes, 0, SEEK_END) ;
psf->filelength = psf_ftell (psf->filedes) ;
psf->sf.samples = pima->samplesperblock * pima->blockcount ;
psf->datalength = psf->filelength - psf->dataoffset ;
if (psf->write_header)
psf->write_header (psf) ;
} ;
free (psf->fdata) ;
psf->fdata = NULL ;
return 0 ;
} /+* aiff_ima_close *+/
-*/
/*============================================================================================
** IMA ADPCM Read Functions.
*/
static int
ima_reader_init (SF_PRIVATE *psf, int blockalign, int samplesperblock)
{ IMA_ADPCM_PRIVATE *pima ;
int pimasize, count ;
if (psf->mode != SFM_READ)
return SFE_BAD_MODE_RW ;
pimasize = sizeof (IMA_ADPCM_PRIVATE) + blockalign + 3 * psf->sf.channels * samplesperblock ;
if (! (pima = malloc (pimasize)))
return SFE_MALLOC_FAILED ;
psf->fdata = (void*) pima ;
memset (pima, 0, pimasize) ;
pima->block = (unsigned char*) pima->data ;
pima->samples = (short*) (pima->data + blockalign) ;
pima->channels = psf->sf.channels ;
pima->blocksize = blockalign ;
pima->samplesperblock = samplesperblock ;
psf->filelength = psf_get_filelen (psf->filedes) ;
psf->datalength = (psf->dataend) ? psf->dataend - psf->dataoffset :
psf->filelength - psf->dataoffset ;
if (psf->datalength % pima->blocksize)
pima->blocks = psf->datalength / pima->blocksize + 1 ;
else
pima->blocks = psf->datalength / pima->blocksize ;
count = 2 * (pima->blocksize - 4 * pima->channels) / pima->channels + 1 ;
if (pima->samplesperblock != count)
psf_log_printf (psf, "*** Warning : samplesperblock should be %d.\n", count) ;
psf->sf.samples = pima->samplesperblock * pima->blocks ;
ima_decode_block (psf, pima) ; /* Read first block. */
psf->read_short = ima_read_s ;
psf->read_int = ima_read_i ;
psf->read_float = ima_read_f ;
psf->read_double = ima_read_d ;
return 0 ;
} /* ima_reader_init */
static int
ima_decode_block (SF_PRIVATE *psf, IMA_ADPCM_PRIVATE *pima)
{ int chan, k, current, blockindex, index, indexstart ;
short step, diff, bytecode, stepindex [2] ;
pima->blockcount ++ ;
pima->samplecount = 0 ;
if (pima->blockcount > pima->blocks)
{ memset (pima->samples, 0, pima->samplesperblock * pima->channels * sizeof (short)) ;
return 1 ;
} ;
if ((k = psf_fread (pima->block, 1, pima->blocksize, psf->filedes)) != pima->blocksize)
psf_log_printf (psf, "*** Warning : short read (%d != %d).\n", k, pima->blocksize) ;
/* Read and check the block header. */
for (chan = 0 ; chan < pima->channels ; chan++)
{ current = pima->block [chan*4] | (pima->block [chan*4+1] << 8) ;
if (current & 0x8000)
current -= 0x10000 ;
stepindex [chan] = pima->block [chan*4+2] ;
if (stepindex [chan] < 0)
stepindex [chan] = 0 ;
else if (stepindex [chan] > 88)
stepindex [chan] = 88 ;
if (pima->block [chan*4+3] != 0)
psf_log_printf (psf, "IMA ADPCM synchronisation error.\n") ;
pima->samples [chan] = current ;
/* psf_log_printf (psf, "block %d : channel %d (current, index) : (%d, %d)\n",
** pima->blockcount, chan, current, stepindex [chan]) ;
*/
} ;
/* Pull apart the packed 4 bit samples and store them in their
** correct sample positions.
*/
blockindex = 4 * pima->channels ;
indexstart = pima->channels ;
while (blockindex < pima->blocksize)
{ for (chan = 0 ; chan < pima->channels ; chan++)
{ index = indexstart + chan ;
for (k = 0 ; k < 4 ; k++)
{ bytecode = pima->block [blockindex++] ;
pima->samples [index] = bytecode & 0x0F ;
index += pima->channels ;
pima->samples [index] = (bytecode >> 4) & 0x0F ;
index += pima->channels ;
} ;
} ;
indexstart += 8 * pima->channels ;
} ;
/* Decode the encoded 4 bit samples. */
for (k = pima->channels ; k < (pima->samplesperblock * pima->channels) ; k ++)
{ chan = (pima->channels > 1) ? (k % 2) : 0 ;
bytecode = pima->samples [k] & 0xF ;
step = ima_step_size [stepindex [chan]] ;
current = pima->samples [k - pima->channels] ;
diff = step >> 3 ;
if (bytecode & 1)
diff += step >> 2 ;
if (bytecode & 2)
diff += step >> 1 ;
if (bytecode & 4)
diff += step ;
if (bytecode & 8)
diff = -diff ;
current += diff ;
if (current > 32767)
current = 32767;
else if (current < -32768)
current = -32768 ;
stepindex [chan] += ima_index_adjust [bytecode] ;
if (stepindex [chan] < 0)
stepindex [chan] = 0 ;
else if (stepindex [chan] > 88)
stepindex [chan] = 88 ;
pima->samples [k] = current ;
} ;
return 1 ;
} /* ima_decode_block */
static int
ima_read_block (SF_PRIVATE *psf, IMA_ADPCM_PRIVATE *pima, short *ptr, sf_count_t len)
{ sf_count_t count, total = 0, index = 0 ;
while (index < len)
{ if (pima->blockcount >= pima->blocks && pima->samplecount >= pima->samplesperblock)
{ memset (&(ptr[index]), 0, (size_t) ((len - index) * sizeof (short))) ;
return total ;
} ;
if (pima->samplecount >= pima->samplesperblock)
ima_decode_block (psf, pima) ;
count = (pima->samplesperblock - pima->samplecount) * pima->channels ;
count = (len - index > count) ? count : len - index ;
memcpy (&(ptr[index]), &(pima->samples [pima->samplecount * pima->channels]), count * sizeof (short)) ;
index += count ;
pima->samplecount += count / pima->channels ;
total = index ;
} ;
return total ;
} /* ima_read_block */
static sf_count_t
ima_read_s (SF_PRIVATE *psf, short *ptr, sf_count_t len)
{ IMA_ADPCM_PRIVATE *pima ;
int total ;
if (! psf->fdata)
return 0 ;
pima = (IMA_ADPCM_PRIVATE*) psf->fdata ;
total = ima_read_block (psf, pima, ptr, len) ;
return total ;
} /* ima_read_s */
static sf_count_t
ima_read_i (SF_PRIVATE *psf, int *ptr, sf_count_t len)
{ IMA_ADPCM_PRIVATE *pima ;
short *sptr ;
int k, bufferlen, readcount = 0, count ;
int index = 0, total = 0 ;
if (! psf->fdata)
return 0 ;
pima = (IMA_ADPCM_PRIVATE*) psf->fdata ;
sptr = (short*) psf->buffer ;
bufferlen = SF_BUFFER_LEN / sizeof (short) ;
while (len > 0)
{ readcount = (len >= bufferlen) ? bufferlen : len ;
count = ima_read_block (psf, pima, sptr, readcount) ;
for (k = 0 ; k < readcount ; k++)
ptr [index + k] = ((int) sptr [k]) << 16 ;
index += readcount ;
total += count ;
len -= readcount ;
} ;
return total ;
} /* ima_read_i */
static sf_count_t
ima_read_f (SF_PRIVATE *psf, float *ptr, sf_count_t len)
{ IMA_ADPCM_PRIVATE *pima ;
short *sptr ;
int k, bufferlen, readcount = 0, count ;
int index = 0, total = 0 ;
float normfact ;
if (! psf->fdata)
return 0 ;
pima = (IMA_ADPCM_PRIVATE*) psf->fdata ;
normfact = (psf->norm_float == SF_TRUE) ? 1.0 / ((float) 0x8000) : 1.0 ;
sptr = (short*) psf->buffer ;
bufferlen = SF_BUFFER_LEN / sizeof (short) ;
while (len > 0)
{ readcount = (len >= bufferlen) ? bufferlen : len ;
count = ima_read_block (psf, pima, sptr, readcount) ;
for (k = 0 ; k < readcount ; k++)
ptr [index + k] = normfact * (float) (sptr [k]) ;
index += readcount ;
total += count ;
len -= readcount ;
} ;
return total ;
} /* ima_read_f */
static sf_count_t
ima_read_d (SF_PRIVATE *psf, double *ptr, sf_count_t len)
{ IMA_ADPCM_PRIVATE *pima ;
short *sptr ;
int k, bufferlen, readcount = 0, count ;
int index = 0, total = 0 ;
double normfact ;
if (! psf->fdata)
return 0 ;
pima = (IMA_ADPCM_PRIVATE*) psf->fdata ;
normfact = (psf->norm_double == SF_TRUE) ? 1.0 / ((double) 0x8000) : 1.0 ;
sptr = (short*) psf->buffer ;
bufferlen = SF_BUFFER_LEN / sizeof (short) ;
while (len > 0)
{ readcount = (len >= bufferlen) ? bufferlen : len ;
count = ima_read_block (psf, pima, sptr, readcount) ;
for (k = 0 ; k < readcount ; k++)
ptr [index + k] = normfact * (double) (sptr [k]) ;
index += readcount ;
total += count ;
len -= readcount ;
} ;
return total ;
} /* ima_read_d */
static sf_count_t
ima_seek (SF_PRIVATE *psf, int mode, sf_count_t offset)
{ IMA_ADPCM_PRIVATE *pima ;
int newblock, newsample ;
if (! psf->fdata)
return 0 ;
pima = (IMA_ADPCM_PRIVATE*) psf->fdata ;
if (! (psf->datalength && psf->dataoffset))
{ psf->error = SFE_BAD_SEEK ;
return ((sf_count_t) -1) ;
} ;
if (offset == 0)
{ psf_fseek (psf->filedes, psf->dataoffset, SEEK_SET) ;
pima->blockcount = 0 ;
ima_decode_block (psf, pima) ;
pima->samplecount = 0 ;
return 0 ;
} ;
if (offset < 0 || offset > pima->blocks * pima->samplesperblock)
{ psf->error = SFE_BAD_SEEK ;
return ((sf_count_t) -1) ;
} ;
newblock = offset / pima->samplesperblock ;
newsample = offset % pima->samplesperblock ;
if (mode == SFM_READ)
{ psf_fseek (psf->filedes, psf->dataoffset + newblock * pima->blocksize, SEEK_SET) ;
pima->blockcount = newblock ;
ima_decode_block (psf, pima) ;
pima->samplecount = newsample ;
}
else
{ /* What to do about write??? */
psf->error = SFE_BAD_SEEK ;
return ((sf_count_t) -1) ;
} ;
return newblock * pima->samplesperblock + newsample ;
} /* ima_seek */
/*==========================================================================================
** IMA ADPCM Write Functions.
*/
static int
ima_writer_init (SF_PRIVATE *psf, int blockalign)
{ IMA_ADPCM_PRIVATE *pima ;
int samplesperblock ;
unsigned int pimasize ;
if (psf->mode != SFM_WRITE)
return SFE_BAD_MODE_RW ;
samplesperblock = 2 * (blockalign - 4 * psf->sf.channels) / psf->sf.channels + 1 ;
pimasize = sizeof (IMA_ADPCM_PRIVATE) + blockalign + 3 * psf->sf.channels * samplesperblock ;
if (! (pima = malloc (pimasize)))
return SFE_MALLOC_FAILED ;
psf->fdata = (void*) pima ;
memset (pima, 0, pimasize) ;
pima->channels = psf->sf.channels ;
pima->blocksize = blockalign ;
pima->samplesperblock = samplesperblock ;
pima->block = (unsigned char*) pima->data ;
pima->samples = (short*) (pima->data + blockalign) ;
pima->samplecount = 0 ;
psf->write_short = ima_write_s ;
psf->write_int = ima_write_i ;
psf->write_float = ima_write_f ;
psf->write_double = ima_write_d ;
return 0 ;
} /* ima_writer_init */
/*==========================================================================================
*/
static int
ima_encode_block (SF_PRIVATE *psf, IMA_ADPCM_PRIVATE *pima)
{ int chan, k, step, diff, vpdiff, blockindex, index, indexstart ;
short bytecode, mask ;
/* Encode the block header. */
for (chan = 0 ; chan < pima->channels ; chan++)
{ pima->block [chan*4] = pima->samples [chan] & 0xFF ;
pima->block [chan*4+1] = (pima->samples [chan] >> 8) & 0xFF ;
pima->block [chan*4+2] = pima->stepindex [chan] ;
pima->block [chan*4+3] = 0 ;
} ;
pima->previous [0] = pima->samples [0] ;
pima->previous [1] = pima->samples [1] ;
/* Encode the samples as 4 bit. */
for (k = pima->channels ; k < (pima->samplesperblock * pima->channels) ; k ++)
{ chan = (pima->channels > 1) ? (k % 2) : 0 ;
diff = pima->samples [k] - pima->previous [chan] ;
bytecode = 0 ;
step = ima_step_size [pima->stepindex [chan]] ;
vpdiff = step >> 3 ;
if (diff < 0)
{ bytecode = 8 ;
diff = -diff ;
} ;
mask = 4 ;
while (mask)
{ if (diff >= step)
{ bytecode |= mask ;
diff -= step ;
vpdiff += step ;
} ;
step >>= 1 ;
mask >>= 1 ;
} ;
if (bytecode & 8)
pima->previous [chan] -= vpdiff ;
else
pima->previous [chan] += vpdiff ;
if (pima->previous [chan] > 32767)
pima->previous [chan] = 32767;
else if (pima->previous [chan] < -32768)
pima->previous [chan] = -32768;
pima->stepindex [chan] += ima_index_adjust [bytecode] ;
if (pima->stepindex [chan] < 0)
pima->stepindex [chan] = 0 ;
else if (pima->stepindex [chan] > 88)
pima->stepindex [chan] = 88 ;
pima->samples [k] = bytecode ;
} ;
/* Pack the 4 bit encoded samples. */
blockindex = 4 * pima->channels ;
indexstart = pima->channels ;
while (blockindex < pima->blocksize)
{ for (chan = 0 ; chan < pima->channels ; chan++)
{ index = indexstart + chan ;
for (k = 0 ; k < 4 ; k++)
{ pima->block [blockindex] = pima->samples [index] & 0x0F ;
index += pima->channels ;
pima->block [blockindex] |= (pima->samples [index] << 4) & 0xF0 ;
index += pima->channels ;
blockindex ++ ;
} ;
} ;
indexstart += 8 * pima->channels ;
} ;
/* Write the block to disk. */
if ((k = psf_fwrite (pima->block, 1, pima->blocksize, psf->filedes)) != pima->blocksize)
psf_log_printf (psf, "*** Warning : short write (%d != %d).\n", k, pima->blocksize) ;
memset (pima->samples, 0, pima->samplesperblock * sizeof (short)) ;
pima->samplecount = 0 ;
pima->blockcount ++ ;
return 1 ;
} /* ima_encode_block */
static int
ima_write_block (SF_PRIVATE *psf, IMA_ADPCM_PRIVATE *pima, short *ptr, sf_count_t len)
{ int count, total = 0, index = 0 ;
while (index < len)
{ count = (pima->samplesperblock - pima->samplecount) * pima->channels ;
if (count > len - index)
count = len - index ;
memcpy (&(pima->samples [pima->samplecount * pima->channels]), &(ptr [index]), count * sizeof (short)) ;
index += count ;
pima->samplecount += count / pima->channels ;
total = index ;
if (pima->samplecount >= pima->samplesperblock)
ima_encode_block (psf, pima) ;
} ;
return total ;
} /* ima_write_block */
static sf_count_t
ima_write_s (SF_PRIVATE *psf, short *ptr, sf_count_t len)
{ IMA_ADPCM_PRIVATE *pima ;
int total ;
if (! psf->fdata)
return 0 ;
pima = (IMA_ADPCM_PRIVATE*) psf->fdata ;
total = ima_write_block (psf, pima, ptr, len) ;
return total ;
} /* ima_write_s */
static sf_count_t
ima_write_i (SF_PRIVATE *psf, int *ptr, sf_count_t len)
{ IMA_ADPCM_PRIVATE *pima ;
short *sptr ;
int k, bufferlen, writecount = 0, count ;
int index = 0, total = 0 ;
if (! psf->fdata)
return 0 ;
pima = (IMA_ADPCM_PRIVATE*) psf->fdata ;
sptr = (short*) psf->buffer ;
bufferlen = SF_BUFFER_LEN / sizeof (short) ;
while (len > 0)
{ writecount = (len >= bufferlen) ? bufferlen : len ;
for (k = 0 ; k < writecount ; k++)
sptr [k] = ptr [index + k] >> 16 ;
count = ima_write_block (psf, pima, sptr, writecount) ;
index += writecount ;
total += count ;
len -= writecount ;
} ;
return total ;
} /* ima_write_i */
static sf_count_t
ima_write_f (SF_PRIVATE *psf, float *ptr, sf_count_t len)
{ IMA_ADPCM_PRIVATE *pima ;
short *sptr ;
int k, bufferlen, writecount = 0, count ;
int index = 0, total = 0 ;
float normfact ;
if (! psf->fdata)
return 0 ;
pima = (IMA_ADPCM_PRIVATE*) psf->fdata ;
normfact = (psf->norm_float == SF_TRUE) ? ((float) 0x8000) : 1.0 ;
sptr = (short*) psf->buffer ;
bufferlen = SF_BUFFER_LEN / sizeof (short) ;
while (len > 0)
{ writecount = (len >= bufferlen) ? bufferlen : len ;
for (k = 0 ; k < writecount ; k++)
sptr [k] = lrintf (normfact * ptr [index + k]) ;
count = ima_write_block (psf, pima, sptr, writecount) ;
index += writecount ;
total += count ;
len -= writecount ;
} ;
return total ;
} /* ima_write_f */
static sf_count_t
ima_write_d (SF_PRIVATE *psf, double *ptr, sf_count_t len)
{ IMA_ADPCM_PRIVATE *pima ;
short *sptr ;
int k, bufferlen, writecount = 0, count ;
int index = 0, total = 0 ;
double normfact ;
if (! psf->fdata)
return 0 ;
pima = (IMA_ADPCM_PRIVATE*) psf->fdata ;
normfact = (psf->norm_double == SF_TRUE) ? ((double) 0x8000) : 1.0 ;
sptr = (short*) psf->buffer ;
bufferlen = SF_BUFFER_LEN / sizeof (short) ;
while (len > 0)
{ writecount = (len >= bufferlen) ? bufferlen : len ;
for (k = 0 ; k < writecount ; k++)
sptr [k] = lrint (normfact * ptr [index + k]) ;
count = ima_write_block (psf, pima, sptr, writecount) ;
index += writecount ;
total += count ;
len -= writecount ;
} ;
return total ;
} /* ima_write_d */