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rockbox/apps/codecs/libpcm/dvi_adpcm.c

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Commit FS#10422 by Yoshihisa Uchida. Seperates WAV and AIFF parsing from PCM decoding by introducing libpcm, a library for decoding linear and non-uniform PCM independently of the container format. git-svn-id: svn://svn.rockbox.org/rockbox/trunk@24346 a1c6a512-1295-4272-9138-f99709370657
2010-01-27 17:25:10 +00:00
/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2005 Dave Chapman
* Copyright (C) 2009 Yoshihisa Uchida
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "codeclib.h"
#include "pcm_common.h"
libpcm: add missing #include and set svn:keywords git-svn-id: svn://svn.rockbox.org/rockbox/trunk@24365 a1c6a512-1295-4272-9138-f99709370657
2010-01-28 17:28:27 +00:00
#include "support_formats.h"
Commit FS#10422 by Yoshihisa Uchida. Seperates WAV and AIFF parsing from PCM decoding by introducing libpcm, a library for decoding linear and non-uniform PCM independently of the container format. git-svn-id: svn://svn.rockbox.org/rockbox/trunk@24346 a1c6a512-1295-4272-9138-f99709370657
2010-01-27 17:25:10 +00:00
/*
* Intel DVI ADPCM
*/
static const uint16_t dvi_adpcm_steptab[89] ICONST_ATTR = {
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 const int dvi_adpcm_indextab4[8] ICONST_ATTR = {
-1, -1, -1, -1, 2, 4, 6, 8 };
static const int dvi_adpcm_indextab3[4] ICONST_ATTR = { -1, -1, 1, 2 };
static struct pcm_format *fmt;
static bool set_format(struct pcm_format *format, const unsigned char *fmtpos)
{
fmt = format;
(void)fmtpos;
if (fmt->bitspersample != 4 && fmt->bitspersample != 3)
{
DEBUGF("CODEC_ERROR: dvi_adpcm must have 3 or 4 bitspersample\n");
return false;
}
if (fmt->size < 2) {
DEBUGF("CODEC_ERROR: dvi_adpcm is missing SamplesPerBlock value\n");
return false;
}
/* chunksize is computed so that one chunk is about 1/50s.
* this make 4096 for 44.1kHz 16bits stereo.
* It also has to be a multiple of blockalign */
fmt->chunksize = (1 + fmt->avgbytespersec / (50*fmt->blockalign))*fmt->blockalign;
/* check that the output buffer is big enough (convert to samplespersec,
then round to the blockalign multiple below) */
if ((((uint64_t)fmt->chunksize * ci->id3->frequency * fmt->channels * fmt->bitspersample)>>3)
/(uint64_t)fmt->avgbytespersec >= PCM_CHUNK_SIZE)
fmt->chunksize = ((uint64_t)PCM_CHUNK_SIZE * fmt->avgbytespersec
/((uint64_t)ci->id3->frequency * fmt->channels * 2
* fmt->blockalign)) * fmt->blockalign;
return true;
}
static uint32_t get_seek_pos(long seek_time)
{
uint32_t newpos;
/* use avgbytespersec to round to the closest blockalign multiple,
add firstblockposn. 64-bit casts to avoid overflows. */
newpos = (((uint64_t)fmt->avgbytespersec*(seek_time - 1))
/ (1000LL*fmt->blockalign))*fmt->blockalign;
return newpos;
}
static int decode_dvi_adpcm(const uint8_t *inbuf, size_t inbufsize,
int32_t *outbuf, size_t *outbufcount)
{
size_t nsamples = 0;
int sample[2];
int samplecode[32][2];
int i;
int stepindex[2];
int c;
int diff;
int step;
int codem;
int code;
if (fmt->bitspersample != 4 && fmt->bitspersample != 3) {
DEBUGF("decode_dvi_adpcm: wrong bitspersample\n");
return CODEC_ERROR;
}
/* decode block header */
for (c = 0; c < fmt->channels && inbufsize >= 4; c++) {
/* decode + push first sample */
sample[c] = (short)(inbuf[0]|(inbuf[1]<<8));/* need cast for sign-extend */
outbuf[c] = sample[c] << 13;
nsamples++;
stepindex[c] = inbuf[2];
/* check for step table index overflow */
if (stepindex[c] > 88) {
DEBUGF("decode_dvi_adpcm: stepindex[%d]=%d>88\n",c,stepindex[c]);
return CODEC_ERROR;
}
inbuf += 4;
inbufsize -= 4;
}
if (fmt->bitspersample == 4) {
while (inbufsize >= (size_t)(fmt->channels*4) &&
(nsamples + (fmt->channels*8) <= *outbufcount))
{
for (c = 0; c < fmt->channels; c++)
{
samplecode[0][c] = inbuf[0]&0xf;
samplecode[1][c] = inbuf[0]>>4;
samplecode[2][c] = inbuf[1]&0xf;
samplecode[3][c] = inbuf[1]>>4;
samplecode[4][c] = inbuf[2]&0xf;
samplecode[5][c] = inbuf[2]>>4;
samplecode[6][c] = inbuf[3]&0xf;
samplecode[7][c] = inbuf[3]>>4;
inbuf += 4;
inbufsize -= 4;
}
for (i = 0; i < 8; i++)
{
for (c = 0; c < fmt->channels; c++)
{
step = dvi_adpcm_steptab[stepindex[c]];
codem = samplecode[i][c];
code = codem & 0x07;
/* adjust the step table index */
stepindex[c] += dvi_adpcm_indextab4[code];
/* check for step table index overflow and underflow */
if (stepindex[c] > 88)
stepindex[c] = 88;
else if (stepindex[c] < 0)
stepindex[c] = 0;
/* calculate the difference */
#ifdef STRICT_IMA
diff = 0;
if (code & 4)
diff += step;
step = step >> 1;
if (code & 2)
diff += step;
step = step >> 1;
if (code & 1)
diff += step;
step = step >> 1;
diff += step;
#else
diff = ((code + code + 1) * step) >> 3; /* faster */
#endif
/* check the sign bit */
/* check for overflow and underflow errors */
if (code != codem)
{
sample[c] -= diff;
if (sample[c] < -32768)
sample[c] = -32768;
}
else
{
sample[c] += diff;
if (sample[c] > 32767)
sample[c] = 32767;
}
/* output the new sample */
outbuf[nsamples] = sample[c] << 13;
nsamples++;
}
}
}
} else { /* bitspersample == 3 */
while (inbufsize >= (uint32_t)(fmt->channels*12) &&
(nsamples + 32*fmt->channels) <= *outbufcount) {
for (c = 0; c < fmt->channels; c++) {
uint16_t bitstream = 0;
int bitsread = 0;
for (i = 0; i < 32 && inbufsize > 0; i++) {
if (bitsread < 3) {
/* read 8 more bits */
bitstream |= inbuf[0]<<bitsread;
bitsread += 8;
inbufsize--;
inbuf++;
}
samplecode[i][c] = bitstream & 7;
bitstream = bitstream>>3;
bitsread -= 3;
}
if (bitsread != 0) {
/* 32*3 = 3 words, so we should end with bitsread==0 */
DEBUGF("decode_dvi_adpcm: error in implementation\n");
return CODEC_ERROR;
}
}
for (i = 0; i < 32; i++) {
for (c = 0; c < fmt->channels; c++) {
step = dvi_adpcm_steptab[stepindex[c]];
codem = samplecode[i][c];
code = codem & 0x03;
/* adjust the step table index */
stepindex[c] += dvi_adpcm_indextab3[code];
/* check for step table index overflow and underflow */
if (stepindex[c] > 88)
stepindex[c] = 88;
else if (stepindex[c] < 0)
stepindex[c] = 0;
/* calculate the difference */
#ifdef STRICT_IMA
diff = 0;
if (code & 2)
diff += step;
step = step >> 1;
if (code & 1)
diff += step;
step = step >> 1;
diff += step;
#else
diff = ((code + code + 1) * step) >> 3; /* faster */
#endif
/* check the sign bit */
/* check for overflow and underflow errors */
if (code != codem) {
sample[c] -= diff;
if (sample[c] < -32768)
sample[c] = -32768;
}
else {
sample[c] += diff;
if (sample[c] > 32767)
sample[c] = 32767;
}
/* output the new sample */
outbuf[nsamples] = sample[c] << 13;
nsamples++;
}
}
}
}
if (nsamples > *outbufcount) {
DEBUGF("decode_dvi_adpcm: output buffer overflow!\n");
return CODEC_ERROR;
}
*outbufcount = nsamples;
if (inbufsize != 0) {
DEBUGF("decode_dvi_adpcm: n=%d unprocessed bytes\n", (int)inbufsize);
}
return CODEC_OK;
}
static int decode(const uint8_t *inbuf, size_t inbufsize,
int32_t *outbuf, int *outbufsize)
{
unsigned int i;
unsigned int nblocks = fmt->chunksize / fmt->blockalign;
(void)inbufsize;
for (i = 0; i < nblocks; i++)
{
size_t decodedsize = fmt->samplesperblock * fmt->channels;
if (decode_dvi_adpcm(inbuf + i * fmt->blockalign, fmt->blockalign,
outbuf + i * fmt->samplesperblock * fmt->channels,
&decodedsize) != CODEC_OK) {
return CODEC_ERROR;
}
}
*outbufsize = nblocks * fmt->samplesperblock;
return CODEC_OK;
}
static const struct pcm_codec codec = {
set_format,
get_seek_pos,
decode,
};
const struct pcm_codec *get_dvi_adpcm_codec(void)
{
return &codec;
}
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