cog/Frameworks/WavPack/Files/unpack3.c

1700 lines
59 KiB
C

////////////////////////////////////////////////////////////////////////////
// **** WAVPACK **** //
// Hybrid Lossless Wavefile Compressor //
// Copyright (c) 1998 - 2013 Conifer Software. //
// All Rights Reserved. //
// Distributed under the BSD Software License (see license.txt) //
////////////////////////////////////////////////////////////////////////////
// unpack3.c
// This module provides unpacking for WavPack files prior to version 4.0,
// not including "raw" files. As these modes are all obsolete and are no
// longer written, this code will not be fully documented other than the
// global functions. However, full documenation is provided in the version
// 3.97 source code. Note that this module does only the low-level sample
// unpacking; the actual opening of the file (and obtaining information
// from it) is handled in the unpack3_open.c module.
#include <stdlib.h>
#include <string.h>
#include "wavpack_local.h"
#include "unpack3.h"
#define ATTEMPT_ERROR_MUTING
static int bs_open_read3 (Bitstream3 *bs, WavpackStreamReader64 *reader, void *id);
static uint32_t bs_unused_bytes (Bitstream3 *bs);
static unsigned char *bs_unused_data (Bitstream3 *bs);
static void init_words3 (WavpackStream3 *wps);
//////////////////////////////// local macros /////////////////////////////////
#define apply_weight_n(bits, weight, sample) ((weight * sample + (1 << (bits - 1))) >> bits)
#define update_weight_n(bits, weight, source, result) \
if (source && result) { \
if ((source ^ result) >= 0) { if (weight++ == (1 << bits)) weight--; } \
else if (weight-- == min_weight) weight++; \
}
#define apply_weight24(weight, sample) (((((sample & 0xffff) * weight) >> 7) + \
(((sample & ~0xffff) >> 7) * weight) + 1) >> 1)
#define update_weight2(weight, source, result) \
if (source && result) { \
if ((source ^ result) >= 0) { if (weight++ == 256) weight--; } \
else if (weight-- == min_weight) weight++; \
}
//////////////////////////////// local tables ///////////////////////////////
// These three tables specify the characteristics of the decorrelation filters.
// Each term represents one layer of the sequential filter, where positive
// values indicate the relative sample involved from the same channel (1=prev)
// while -1 and -2 indicate cross channel decorrelation (in stereo only). The
// "simple_terms" table is no longer used for writing, but is kept for older
// file decoding.
static const signed char extreme_terms [] = { 1,1,1,2,4,-1,1,2,3,6,-2,8,5,7,4,1,2,3 };
static const signed char default_terms [] = { 1,1,1,-1,2,1,-2 };
static const signed char simple_terms [] = { 1,1,1,1 };
///////////////////////////// executable code ////////////////////////////////
// This function initializes everything required to unpack WavPack
// bitstreams and must be called before any unpacking is performed. Note
// that the (WavpackHeader3 *) in the WavpackStream3 struct must be valid.
void unpack_init3 (WavpackStream3 *wps)
{
int flags = wps->wphdr.flags;
struct decorr_pass *dpp;
int ti;
CLEAR (wps->decorr_passes);
CLEAR (wps->dc);
if (flags & EXTREME_DECORR) {
for (dpp = wps->decorr_passes, ti = 0; ti < sizeof (extreme_terms); ti++)
if (extreme_terms [sizeof (extreme_terms) - ti - 1] > 0 || (flags & CROSS_DECORR))
dpp++->term = extreme_terms [sizeof (extreme_terms) - ti - 1];
}
else if (flags & NEW_DECORR_FLAG) {
for (dpp = wps->decorr_passes, ti = 0; ti < sizeof (default_terms); ti++)
if (default_terms [sizeof (default_terms) - ti - 1] > 0 || (flags & CROSS_DECORR))
dpp++->term = default_terms [sizeof (default_terms) - ti - 1];
}
else
for (dpp = wps->decorr_passes, ti = 0; ti < sizeof (simple_terms); ti++)
dpp++->term = simple_terms [sizeof (simple_terms) - ti - 1];
wps->num_terms = (int)(dpp - wps->decorr_passes);
init_words3 (wps);
}
#ifndef NO_SEEKING
// This function returns the size (in bytes) required to save the unpacking
// context. Note that the (WavpackHeader3 *) in the WavpackStream3 struct
// must be valid.
static int unpack_size (WavpackStream3 *wps)
{
int flags = wps->wphdr.flags, byte_sum = 0, tcount;
struct decorr_pass *dpp;
byte_sum += sizeof (wps->wvbits);
if (flags & WVC_FLAG)
byte_sum += sizeof (wps->wvcbits);
if (wps->wphdr.version == 3) {
if (wps->wphdr.bits)
byte_sum += sizeof (wps->w4);
else
byte_sum += sizeof (wps->w1);
byte_sum += sizeof (wps->w3) + sizeof (wps->dc.crc);
}
else
byte_sum += sizeof (wps->w2);
if (wps->wphdr.bits)
byte_sum += sizeof (wps->dc.error);
else
byte_sum += sizeof (wps->dc.sum_level) + sizeof (wps->dc.left_level) +
sizeof (wps->dc.right_level) + sizeof (wps->dc.diff_level);
if (flags & OVER_20)
byte_sum += sizeof (wps->dc.last_extra_bits) + sizeof (wps->dc.extra_bits_count);
if (!(flags & EXTREME_DECORR)) {
byte_sum += sizeof (wps->dc.sample);
byte_sum += sizeof (wps->dc.weight);
}
if (flags & (HIGH_FLAG | NEW_HIGH_FLAG))
for (tcount = wps->num_terms, dpp = wps->decorr_passes; tcount--; dpp++) {
if (dpp->term > 0) {
byte_sum += sizeof (dpp->samples_A [0]) * dpp->term;
byte_sum += sizeof (dpp->weight_A);
if (!(flags & MONO_FLAG)) {
byte_sum += sizeof (dpp->samples_B [0]) * dpp->term;
byte_sum += sizeof (dpp->weight_B);
}
}
else {
byte_sum += sizeof (dpp->samples_A [0]) + sizeof (dpp->samples_B [0]);
byte_sum += sizeof (dpp->weight_A) + sizeof (dpp->weight_B);
}
}
return byte_sum;
}
// This function saves the unpacking context at the specified pointer and
// returns the updated pointer. The actual amount of data required can be
// determined beforehand by calling unpack_size() but must be allocated by
// the caller.
static void *unpack_save (WavpackStream3 *wps, void *destin)
{
int flags = wps->wphdr.flags, tcount;
struct decorr_pass *dpp;
SAVE (destin, wps->wvbits);
if (flags & WVC_FLAG)
SAVE (destin, wps->wvcbits);
if (wps->wphdr.version == 3) {
if (wps->wphdr.bits) {
SAVE (destin, wps->w4);
}
else {
SAVE (destin, wps->w1);
}
SAVE (destin, wps->w3);
SAVE (destin, wps->dc.crc);
}
else
SAVE (destin, wps->w2);
if (wps->wphdr.bits) {
SAVE (destin, wps->dc.error);
}
else {
SAVE (destin, wps->dc.sum_level);
SAVE (destin, wps->dc.left_level);
SAVE (destin, wps->dc.right_level);
SAVE (destin, wps->dc.diff_level);
}
if (flags & OVER_20) {
SAVE (destin, wps->dc.last_extra_bits);
SAVE (destin, wps->dc.extra_bits_count);
}
if (!(flags & EXTREME_DECORR)) {
SAVE (destin, wps->dc.sample);
SAVE (destin, wps->dc.weight);
}
if (flags & (HIGH_FLAG | NEW_HIGH_FLAG))
for (tcount = wps->num_terms, dpp = wps->decorr_passes; tcount--; dpp++) {
if (dpp->term > 0) {
int count = dpp->term;
int index = wps->dc.m;
SAVE (destin, dpp->weight_A);
while (count--) {
SAVE (destin, dpp->samples_A [index]);
index = (index + 1) & (MAX_TERM - 1);
}
if (!(flags & MONO_FLAG)) {
count = dpp->term;
index = wps->dc.m;
SAVE (destin, dpp->weight_B);
while (count--) {
SAVE (destin, dpp->samples_B [index]);
index = (index + 1) & (MAX_TERM - 1);
}
}
}
else {
SAVE (destin, dpp->weight_A);
SAVE (destin, dpp->weight_B);
SAVE (destin, dpp->samples_A [0]);
SAVE (destin, dpp->samples_B [0]);
}
}
return destin;
}
#endif
// This monster actually unpacks the WavPack bitstream(s) into the specified
// buffer as longs, and serves as an extension to WavpackUnpackSamples().
// Note that WavPack files created prior to version 4.0 could only contain 16
// or 24 bit values, and these values are right-justified in the 32-bit values.
// So, if the original file contained 16-bit values, then the range of the
// returned longs would be +/- 32K. For maximum clarity, the function is
// broken up into segments that handle various modes. This makes for a few
// extra infrequent flag checks, but makes the code easier to follow because
// the nesting does not become so deep. For maximum efficiency, the conversion
// is isolated to tight loops that handle an entire buffer.
static int32_t FASTCALL get_word1 (WavpackStream3 *wps, int chan);
static int32_t FASTCALL get_old_word1 (WavpackStream3 *wps, int chan);
static int32_t FASTCALL get_word2 (WavpackStream3 *wps, int chan);
static int32_t FASTCALL get_word3 (WavpackStream3 *wps, int chan);
static int32_t FASTCALL get_word4 (WavpackStream3 *wps, int chan, int32_t *correction);
int32_t unpack_samples3 (WavpackContext *wpc, int32_t *buffer, uint32_t sample_count)
{
WavpackStream3 *wps = (WavpackStream3 *) wpc->stream3;
int shift = wps->wphdr.shift, flags = wps->wphdr.flags, min_weight = 0, m = wps->dc.m, tcount;
#ifndef NO_SEEKING
int points_index = wps->sample_index / (((uint32_t) wpc->total_samples >> 8) + 1);
#endif
int32_t min_value, max_value, min_shifted, max_shifted;
int32_t correction [2], crc = wps->dc.crc;
struct decorr_pass *dpp;
int32_t read_word, *bptr;
int32_t sample [2] [2];
int weight [2] [1];
unsigned int i;
#ifdef ATTEMPT_ERROR_MUTING
int32_t mute_limit = (flags & BYTES_3) ? 8388608 : 32768;
int mute_block = 0;
if (wps->wphdr.bits && !(flags & WVC_FLAG)) {
if (wps->wphdr.version < 3)
mute_limit *= 4;
else
mute_limit *= 2;
}
#endif
if (wps->sample_index + sample_count > wpc->total_samples)
sample_count = (uint32_t) (wpc->total_samples - wps->sample_index);
if (!sample_count)
return 0;
if (!wps->sample_index) {
unpack_init3 (wps);
bs_open_read3 (&wps->wvbits, wpc->reader, wpc->wv_in);
if (wpc->wvc_flag)
bs_open_read3 (&wps->wvcbits, wpc->reader, wpc->wvc_in);
}
#ifndef NO_SEEKING
if (!wps->index_points [points_index].saved) {
if (!wps->unpack_data)
wps->unpack_data = (unsigned char *) malloc (256 * (wps->unpack_size = unpack_size (wps)));
wps->index_points [points_index].sample_index = wps->sample_index;
unpack_save (wps, wps->unpack_data + points_index * wps->unpack_size);
wps->index_points [points_index].saved = TRUE;
}
#endif
memcpy (sample, wps->dc.sample, sizeof (sample));
memcpy (weight, wps->dc.weight, sizeof (weight));
if (wps->wphdr.bits) {
if (flags & (NEW_DECORR_FLAG | EXTREME_DECORR))
min_weight = -256;
}
else
if (flags & NEW_DECORR_FLAG)
min_weight = (flags & EXTREME_DECORR) ? -512 : -256;
if (flags & BYTES_3) {
min_shifted = (min_value = -8388608 >> shift) << shift;
max_shifted = (max_value = 8388607 >> shift) << shift;
}
else {
min_shifted = (min_value = -32768 >> shift) << shift;
max_shifted = (max_value = 32767 >> shift) << shift;
}
///////////////// handle version 3 lossless mono data /////////////////////
if (wps->wphdr.version == 3 && !wps->wphdr.bits && (flags & MONO_FLAG)) {
if (flags & FAST_FLAG) {
if (flags & OVER_20)
for (bptr = buffer, i = 0; i < sample_count; ++i) {
int32_t temp;
if ((read_word = get_word3 (wps, 0)) == WORD_EOF)
break;
sample [0] [0] += sample [0] [1] += read_word;
getbits (&temp, 4, &wps->wvbits);
crc = crc * 3 + (temp = (temp & 0xf) + (sample [0] [0] << 4));
*bptr++ = temp;
}
else
for (bptr = buffer, i = 0; i < sample_count; ++i) {
if ((read_word = get_word3 (wps, 0)) == WORD_EOF)
break;
crc = crc * 3 + (sample [0] [0] += sample [0] [1] += read_word);
*bptr++ = sample [0] [0] << shift;
}
}
else if (flags & HIGH_FLAG)
for (bptr = buffer, i = 0; i < sample_count; ++i) {
int32_t temp;
if (flags & NEW_HIGH_FLAG) {
if ((read_word = get_word1 (wps, 0)) == WORD_EOF)
break;
}
else {
if ((read_word = get_old_word1 (wps, 0)) == WORD_EOF)
break;
}
if (flags & EXTREME_DECORR)
for (tcount = wps->num_terms, dpp = wps->decorr_passes; tcount--; dpp++) {
int32_t sam = dpp->samples_A [m];
temp = apply_weight_n (9, dpp->weight_A, sam) + read_word;
update_weight_n (9, dpp->weight_A, sam, read_word);
dpp->samples_A [(m + dpp->term) & (MAX_TERM - 1)] = read_word = temp;
}
else
for (tcount = wps->num_terms, dpp = wps->decorr_passes; tcount--; dpp++) {
int32_t sam = dpp->samples_A [m];
temp = apply_weight_n (8, dpp->weight_A, sam) + read_word;
update_weight_n (8, dpp->weight_A, sam, read_word);
dpp->samples_A [(m + dpp->term) & (MAX_TERM - 1)] = read_word = temp;
}
m = (m + 1) & (MAX_TERM - 1);
if (flags & OVER_20) {
if (wps->dc.extra_bits_count < 8 || !getbit (&wps->wvbits)) {
getbits (&temp, 4, &wps->wvbits);
if ((temp &= 0xf) != wps->dc.last_extra_bits) {
wps->dc.last_extra_bits = temp;
wps->dc.extra_bits_count = 0;
}
else
++wps->dc.extra_bits_count;
}
crc = crc * 3 + (temp = wps->dc.last_extra_bits + (read_word << 4));
*bptr++ = temp;
}
else {
crc = crc * 3 + read_word;
*bptr++ = read_word << shift;
}
}
else
for (bptr = buffer, i = 0; i < sample_count; ++i) {
int32_t temp;
if ((read_word = get_word3 (wps, 0)) == WORD_EOF)
break;
temp = sample [0] [0] + ((sample [0] [1] * weight [0] [0] + 128) >> 8) + read_word;
if ((sample [0] [1] >= 0) == (read_word > 0)) {
if (weight [0] [0]++ == 256)
weight [0] [0]--;
}
else if (weight [0] [0]-- == 0)
weight [0] [0]++;
sample [0] [0] += (sample [0] [1] = temp - sample [0] [0]);
if (flags & OVER_20) {
if (wps->dc.extra_bits_count < 8 || !getbit (&wps->wvbits)) {
getbits (&temp, 4, &wps->wvbits);
if ((temp &= 0xf) != wps->dc.last_extra_bits) {
wps->dc.last_extra_bits = temp;
wps->dc.extra_bits_count = 0;
}
else
++wps->dc.extra_bits_count;
}
crc = crc * 3 + (*bptr++ = temp = wps->dc.last_extra_bits + (sample [0] [0] << 4));
}
else {
crc = crc * 3 + sample [0] [0];
*bptr++ = sample [0] [0] << shift;
}
}
}
//////////////// handle version 3 lossless stereo data ////////////////////
else if (wps->wphdr.version == 3 && !wps->wphdr.bits && !(flags & MONO_FLAG)) {
int32_t left_level = wps->dc.left_level, right_level = wps->dc.right_level;
int32_t sum_level = wps->dc.sum_level, diff_level = wps->dc.diff_level;
if (flags & FAST_FLAG) {
if (flags & OVER_20)
for (bptr = buffer, i = 0; i < sample_count; ++i) {
int32_t sum, diff, temp;
read_word = get_word3 (wps, 0);
if (read_word == WORD_EOF)
break;
sum = (read_word << 1) | ((diff = get_word3 (wps, 1)) & 1);
sample [0] [0] += sample [0] [1] += ((sum + diff) >> 1);
sample [1] [0] += sample [1] [1] += ((sum - diff) >> 1);
getbits (&temp, 8, &wps->wvbits);
crc = crc * 3 + (*bptr++ = (sample [0] [0] << 4) + ((temp >> 4) & 0xf));
crc = crc * 3 + (*bptr++ = (sample [1] [0] << 4) + (temp & 0xf));
}
else
for (bptr = buffer, i = 0; i < sample_count; ++i) {
int32_t sum, diff;
read_word = get_word3 (wps, 0);
if (read_word == WORD_EOF)
break;
sum = (read_word << 1) | ((diff = get_word3 (wps, 1)) & 1);
sample [0] [1] += ((sum + diff) >> 1);
sample [1] [1] += ((sum - diff) >> 1);
crc = crc * 3 + (sample [0] [0] += sample [0] [1]);
crc = crc * 3 + (sample [1] [0] += sample [1] [1]);
*bptr++ = sample [0] [0] << shift;
*bptr++ = sample [1] [0] << shift;
}
}
else if (flags & HIGH_FLAG) {
for (bptr = buffer, i = 0; i < sample_count; ++i) {
int32_t sum, left, right, diff, left2, right2, extra_bits, next_word;
if (flags & CROSS_DECORR) {
left = get_word1 (wps, 0);
if (left == WORD_EOF)
break;
right = get_word1 (wps, 1);
}
else {
if (flags & NEW_HIGH_FLAG) {
read_word = get_word1 (wps, 0);
if (read_word == WORD_EOF)
break;
next_word = get_word1 (wps, 1);
if (right_level > left_level) {
if (left_level + right_level < sum_level + diff_level && right_level < diff_level) {
sum = (right = read_word) + (left = next_word);
diff = left - right;
}
else {
diff = read_word;
if (sum_level < left_level) {
sum = (next_word << 1) | (diff & 1);
left = (sum + diff) >> 1;
right = (sum - diff) >> 1;
}
else
sum = next_word + (right = (left = next_word) - diff);
}
}
else {
if (left_level + right_level < sum_level + diff_level && left_level < diff_level) {
sum = (left = read_word) + (right = next_word);
diff = left - right;
}
else {
diff = read_word;
if (sum_level < right_level) {
sum = (next_word << 1) | (diff & 1);
left = (sum + diff) >> 1;
right = (sum - diff) >> 1;
}
else
sum = (left = diff + (right = next_word)) + next_word;
}
}
}
else {
read_word = get_old_word1 (wps, 0);
if (read_word == WORD_EOF)
break;
next_word = get_old_word1 (wps, 1);
if (sum_level <= right_level && sum_level <= left_level) {
sum = (next_word << 1) | (read_word & 1);
left = (sum + read_word) >> 1;
right = (sum - read_word) >> 1;
}
else if (left_level <= right_level)
sum = next_word + (right = (left = next_word) - read_word);
else
sum = next_word + (left = read_word + (right = next_word));
diff = left - right;
}
sum_level = sum_level - (sum_level >> 8) + labs (sum >> 1);
left_level = left_level - (left_level >> 8) + labs (left);
right_level = right_level - (right_level >> 8) + labs (right);
diff_level = diff_level - (diff_level >> 8) + labs (diff);
if (flags & JOINT_STEREO) {
left = diff;
right = sum >> 1;
}
}
if (flags & EXTREME_DECORR) {
for (tcount = wps->num_terms, dpp = wps->decorr_passes; tcount--; dpp++)
if (dpp->term > 0) {
int32_t sam_A = dpp->samples_A [m], sam_B = dpp->samples_B [m];
int k = (m + dpp->term) & (MAX_TERM - 1);
left2 = apply_weight_n (9, dpp->weight_A, sam_A) + left;
right2 = apply_weight_n (9, dpp->weight_B, sam_B) + right;
update_weight_n (9, dpp->weight_A, sam_A, left);
update_weight_n (9, dpp->weight_B, sam_B, right);
dpp->samples_A [k] = left = left2;
dpp->samples_B [k] = right = right2;
}
else if (dpp->term == -1) {
left2 = left + apply_weight_n (9, dpp->weight_A, dpp->samples_A [0]);
update_weight_n (9, dpp->weight_A, dpp->samples_A [0], left);
left = left2;
right2 = right + apply_weight_n (9, dpp->weight_B, left);
update_weight_n (9, dpp->weight_B, left, right);
dpp->samples_A [0] = right = right2;
}
else {
right2 = right + apply_weight_n (9, dpp->weight_A, dpp->samples_A [0]);
update_weight_n (9, dpp->weight_A, dpp->samples_A [0], right);
right = right2;
left2 = left + apply_weight_n (9, dpp->weight_B, right);
update_weight_n (9, dpp->weight_B, right, left);
dpp->samples_A [0] = left = left2;
}
}
else {
for (tcount = wps->num_terms, dpp = wps->decorr_passes; tcount--; dpp++)
if (dpp->term > 0) {
int32_t sam_A = dpp->samples_A [m], sam_B = dpp->samples_B [m];
int k = (m + dpp->term) & (MAX_TERM - 1);
left2 = apply_weight_n (8, dpp->weight_A, sam_A) + left;
right2 = apply_weight_n (8, dpp->weight_B, sam_B) + right;
update_weight_n (8, dpp->weight_A, sam_A, left);
update_weight_n (8, dpp->weight_B, sam_B, right);
dpp->samples_A [k] = left = left2;
dpp->samples_B [k] = right = right2;
}
else if (dpp->term == -1) {
left2 = left + apply_weight_n (8, dpp->weight_A, dpp->samples_A [0]);
update_weight_n (8, dpp->weight_A, dpp->samples_A [0], left);
left = left2;
right2 = right + apply_weight_n (8, dpp->weight_B, left);
update_weight_n (8, dpp->weight_B, left, right);
dpp->samples_A [0] = right = right2;
}
else {
right2 = right + apply_weight_n (8, dpp->weight_A, dpp->samples_A [0]);
update_weight_n (8, dpp->weight_A, dpp->samples_A [0], right);
right = right2;
left2 = left + apply_weight_n (8, dpp->weight_B, right);
update_weight_n (8, dpp->weight_B, right, left);
dpp->samples_A [0] = left = left2;
}
}
m = (m + 1) & (MAX_TERM - 1);
if (flags & JOINT_STEREO) {
sum = (right << 1) | ((diff = left) & 1);
right = (sum - diff) >> 1;
left = (sum + diff) >> 1;
}
if (flags & OVER_20) {
if (wps->dc.extra_bits_count < 8 || !getbit (&wps->wvbits)) {
getbits (&extra_bits, 8, &wps->wvbits);
if ((extra_bits &= 0xff) != wps->dc.last_extra_bits) {
wps->dc.last_extra_bits = extra_bits;
wps->dc.extra_bits_count = 0;
}
else
++wps->dc.extra_bits_count;
}
crc = crc * 3 + (*bptr++ = left = (left << 4) + (wps->dc.last_extra_bits >> 4));
crc = crc * 3 + (*bptr++ = right = (right << 4) + (wps->dc.last_extra_bits & 0xf));
}
else {
crc = crc * 9 + left * 3 + right;
*bptr++ = left << shift;
*bptr++ = right << shift;
}
}
}
else
for (bptr = buffer, i = 0; i < sample_count; ++i) {
int32_t sum, left, right, left2, right2, extra_bits;
read_word = get_word3 (wps, 0);
if (read_word == WORD_EOF)
break;
if (sum_level <= right_level && sum_level <= left_level) {
sum = (get_word3 (wps, 1) << 1) | (read_word & 1);
left = (sum + read_word) >> 1;
right = (sum - read_word) >> 1;
}
else if (left_level <= right_level) {
right = (left = get_word3 (wps, 1)) - read_word;
sum = left + right;
}
else {
left = read_word + (right = get_word3 (wps, 1));
sum = right + left;
}
sum_level = sum_level - (sum_level >> 8) + labs (sum >> 1);
left_level = left_level - (left_level >> 8) + labs (left);
right_level = right_level - (right_level >> 8) + labs (right);
left2 = sample [0] [0] + ((sample [0] [1] * weight [0] [0] + 128) >> 8) + left;
right2 = sample [1] [0] + ((sample [1] [1] * weight [1] [0] + 128) >> 8) + right;
if ((sample [0] [1] >= 0) == (left > 0)) {
if (weight [0] [0]++ == 256)
weight [0] [0]--;
}
else if (weight [0] [0]-- == 0)
weight [0] [0]++;
if ((sample [1] [1] >= 0) == (right > 0)) {
if (weight [1] [0]++ == 256)
weight [1] [0]--;
}
else if (weight [1] [0]-- == 0)
weight [1] [0]++;
sample [0] [0] += (sample [0] [1] = left2 - sample [0] [0]);
sample [1] [0] += (sample [1] [1] = right2 - sample [1] [0]);
if (flags & OVER_20) {
if (wps->dc.extra_bits_count < 8 || !getbit (&wps->wvbits)) {
getbits (&extra_bits, 8, &wps->wvbits);
if ((extra_bits &= 0xff) != wps->dc.last_extra_bits) {
wps->dc.last_extra_bits = extra_bits;
wps->dc.extra_bits_count = 0;
}
else
++wps->dc.extra_bits_count;
}
crc = crc * 3 + (*bptr++ = left2 = (sample [0] [0] << 4) + (wps->dc.last_extra_bits >> 4));
crc = crc * 3 + (*bptr++ = right2 = (sample [1] [0] << 4) + (wps->dc.last_extra_bits & 0xf));
}
else {
crc = crc * 9 + sample [0] [0] * 3 + sample [1] [0];
*bptr++ = sample [0] [0] << shift;
*bptr++ = sample [1] [0] << shift;
}
}
wps->dc.left_level = left_level;
wps->dc.right_level = right_level;
wps->dc.sum_level = sum_level;
wps->dc.diff_level = diff_level;
}
//////////////// handle version 3 lossy/hybrid mono data //////////////////
else if (wps->wphdr.version == 3 && wps->wphdr.bits && (flags & MONO_FLAG)) {
if (flags & FAST_FLAG)
for (bptr = buffer, i = 0; i < sample_count; ++i) {
if ((read_word = get_word3 (wps, 0)) == WORD_EOF)
break;
crc = crc * 3 + (sample [0] [0] += sample [0] [1] += read_word);
if (sample [0] [0] < min_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [0] [0] < -mute_limit)
mute_block = 1;
#endif
*bptr++ = min_shifted;
}
else if (sample [0] [0] > max_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [0] [0] > mute_limit)
mute_block = 1;
#endif
*bptr++ = max_shifted;
}
else
*bptr++ = sample [0] [0] << shift;
}
else if (flags & (HIGH_FLAG | NEW_HIGH_FLAG))
for (bptr = buffer, i = 0; i < sample_count; ++i) {
int32_t temp;
read_word = (flags & NEW_HIGH_FLAG) ?
get_word4 (wps, 0, correction) : get_word3 (wps, 0);
if (read_word == WORD_EOF)
break;
for (tcount = wps->num_terms, dpp = wps->decorr_passes; tcount--; dpp++) {
int32_t sam = dpp->samples_A [m];
temp = apply_weight24 (dpp->weight_A, sam) + read_word;
update_weight2 (dpp->weight_A, sam, read_word);
dpp->samples_A [(m + dpp->term) & (MAX_TERM - 1)] = read_word = temp;
}
m = (m + 1) & (MAX_TERM - 1);
if (flags & WVC_FLAG) {
if (flags & LOSSY_SHAPE) {
crc = crc * 3 + (read_word += correction [0] + wps->dc.error [0]);
wps->dc.error [0] = -correction [0];
}
else
crc = crc * 3 + (read_word += correction [0]);
*bptr++ = read_word << shift;
}
else {
crc = crc * 3 + read_word;
if (read_word < min_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (read_word < -mute_limit)
mute_block = 1;
#endif
*bptr++ = min_shifted;
}
else if (read_word > max_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (read_word > mute_limit)
mute_block = 1;
#endif
*bptr++ = max_shifted;
}
else
*bptr++ = read_word << shift;
}
}
else
for (bptr = buffer, i = 0; i < sample_count; ++i) {
int32_t new_sample;
if ((read_word = get_word3 (wps, 0)) == WORD_EOF)
break;
new_sample = sample [0] [0] + ((sample [0] [1] * weight [0] [0] + 128) >> 8) + read_word;
if ((sample [0] [1] >= 0) == (read_word > 0)) {
if (weight [0] [0]++ == 256)
weight [0] [0]--;
}
else if (weight [0] [0]-- == 0)
weight [0] [0]++;
sample [0] [1] = new_sample - sample [0] [0];
crc = crc * 3 + (sample [0] [0] = new_sample);
if (sample [0] [0] < min_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [0] [0] < -mute_limit)
mute_block = 1;
#endif
*bptr++ = min_shifted;
}
else if (sample [0] [0] > max_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [0] [0] > mute_limit)
mute_block = 1;
#endif
*bptr++ = max_shifted;
}
else
*bptr++ = sample [0] [0] << shift;
}
}
//////////////// handle version 3 lossy/hybrid stereo data ////////////////
else if (wps->wphdr.version == 3 && wps->wphdr.bits && !(flags & MONO_FLAG)) {
if (flags & FAST_FLAG)
for (bptr = buffer, i = 0; i < sample_count; ++i) {
if ((read_word = get_word3 (wps, 0)) == WORD_EOF)
break;
crc = crc * 3 + (sample [0] [0] += sample [0] [1] += read_word);
if (sample [0] [0] < min_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [0] [0] < -mute_limit)
mute_block = 1;
#endif
*bptr++ = min_shifted;
}
else if (sample [0] [0] > max_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [0] [0] > mute_limit)
mute_block = 1;
#endif
*bptr++ = max_shifted;
}
else
*bptr++ = sample [0] [0] << shift;
crc = crc * 3 + (sample [1] [0] += sample [1] [1] += get_word3 (wps, 1));
if (sample [1] [0] < min_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [1] [0] < -mute_limit)
mute_block = 1;
#endif
*bptr++ = min_shifted;
}
else if (sample [1] [0] > max_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [1] [0] > mute_limit)
mute_block = 1;
#endif
*bptr++ = max_shifted;
}
else
*bptr++ = sample [1] [0] << shift;
}
else if (flags & (HIGH_FLAG | NEW_HIGH_FLAG))
for (bptr = buffer, i = 0; i < sample_count; ++i) {
int32_t left, right, left2, right2, sum, diff;
if (flags & NEW_HIGH_FLAG) {
left = get_word4 (wps, 0, correction);
right = get_word4 (wps, 1, correction + 1);
}
else {
left = get_word3 (wps, 0);
right = get_word3 (wps, 1);
}
if (left == WORD_EOF)
break;
for (tcount = wps->num_terms, dpp = wps->decorr_passes; tcount--; dpp++) {
int32_t sam_A = dpp->samples_A [m], sam_B = dpp->samples_B [m];
int k = (m + dpp->term) & (MAX_TERM - 1);
left2 = apply_weight24 (dpp->weight_A, sam_A) + left;
update_weight2 (dpp->weight_A, sam_A, left);
dpp->samples_A [k] = left = left2;
right2 = apply_weight24 (dpp->weight_B, sam_B) + right;
update_weight2 (dpp->weight_B, sam_B, right);
dpp->samples_B [k] = right = right2;
}
m = (m + 1) & (MAX_TERM - 1);
if (flags & WVC_FLAG) {
if (flags & LOSSY_SHAPE) {
left += correction [0] + wps->dc.error [0];
right += correction [1] + wps->dc.error [1];
wps->dc.error [0] = -correction [0];
wps->dc.error [1] = -correction [1];
}
else {
left += correction [0];
right += correction [1];
}
}
if (flags & JOINT_STEREO) {
right = ((sum = (right << 1) | (left & 1)) - (diff = left)) >> 1;
left = (sum + diff) >> 1;
}
crc = crc * 9 + left * 3 + right;
if (flags & WVC_FLAG) {
*bptr++ = left << shift;
*bptr++ = right << shift;
}
else {
if (left < min_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (left < -mute_limit)
mute_block = 1;
#endif
*bptr++ = min_shifted;
}
else if (left > max_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (left > mute_limit)
mute_block = 1;
#endif
*bptr++ = max_shifted;
}
else
*bptr++ = left << shift;
if (right < min_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (right < -mute_limit)
mute_block = 1;
#endif
*bptr++ = min_shifted;
}
else if (right > max_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (right > mute_limit)
mute_block = 1;
#endif
*bptr++ = max_shifted;
}
else
*bptr++ = right << shift;
}
}
else
for (bptr = buffer, i = 0; i < sample_count; ++i) {
int32_t new_sample;
if ((read_word = get_word3 (wps, 0)) == WORD_EOF)
break;
new_sample = sample [0] [0] + ((sample [0] [1] * weight [0] [0] + 128) >> 8) + read_word;
if ((sample [0] [1] >= 0) == (read_word > 0)) {
if (weight [0] [0]++ == 256)
weight [0] [0]--;
}
else if (weight [0] [0]-- == 0)
weight [0] [0]++;
sample [0] [1] = new_sample - sample [0] [0];
crc = crc * 3 + (sample [0] [0] = new_sample);
read_word = get_word3 (wps, 1);
new_sample = sample [1] [0] + ((sample [1] [1] * weight [1] [0] + 128) >> 8) + read_word;
if ((sample [1] [1] >= 0) == (read_word > 0)) {
if (weight [1] [0]++ == 256)
weight [1] [0]--;
}
else if (weight [1] [0]-- == 0)
weight [1] [0]++;
sample [1] [1] = new_sample - sample [1] [0];
crc = crc * 3 + (sample [1] [0] = new_sample);
if (sample [0] [0] < min_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [0] [0] < -mute_limit)
mute_block = 1;
#endif
*bptr++ = min_shifted;
}
else if (sample [0] [0] > max_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [0] [0] > mute_limit)
mute_block = 1;
#endif
*bptr++ = max_shifted;
}
else
*bptr++ = sample [0] [0] << shift;
if (sample [1] [0] < min_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [1] [0] < -mute_limit)
mute_block = 1;
#endif
*bptr++ = min_shifted;
}
else if (sample [1] [0] > max_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [1] [0] > mute_limit)
mute_block = 1;
#endif
*bptr++ = max_shifted;
}
else
*bptr++ = sample [1] [0] << shift;
}
}
//////////////////// finally, handle version 2 data ///////////////////////
else if (wps->wphdr.version == 2 && (flags & MONO_FLAG))
for (bptr = buffer, i = 0; i < sample_count; ++i) {
if ((read_word = get_word2 (wps, 0)) == WORD_EOF)
break;
sample [0] [0] += sample [0] [1] += read_word;
if (wps->wphdr.bits) {
if (sample [0] [0] < min_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [0] [0] < -mute_limit)
mute_block = 1;
#endif
sample [0] [0] = min_value;
}
else if (sample [0] [0] > max_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [0] [0] > mute_limit)
mute_block = 1;
#endif
sample [0] [0] = max_value;
}
}
*bptr++ = sample [0] [0] << shift;
}
else if (wps->wphdr.version < 3 && !(flags & MONO_FLAG))
for (bptr = buffer, i = 0; i < sample_count; ++i) {
int32_t sum, diff;
read_word = get_word2 (wps, 0);
if (read_word == WORD_EOF)
break;
sum = (read_word << 1) | ((diff = get_word2 (wps, 1)) & 1);
sample [0] [0] += sample [0] [1] += ((sum + diff) >> 1);
sample [1] [0] += sample [1] [1] += ((sum - diff) >> 1);
if (wps->wphdr.bits) {
if (sample [0] [0] < min_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [0] [0] < -mute_limit)
mute_block = 1;
#endif
sample [0] [0] = min_value;
}
else if (sample [0] [0] > max_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [0] [0] > mute_limit)
mute_block = 1;
#endif
sample [0] [0] = max_value;
}
if (sample [1] [0] < min_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [1] [0] < -mute_limit)
mute_block = 1;
#endif
sample [1] [0] = min_value;
}
else if (sample [1] [0] > max_value) {
#ifdef ATTEMPT_ERROR_MUTING
if (sample [1] [0] > mute_limit)
mute_block = 1;
#endif
sample [1] [0] = max_value;
}
}
*bptr++ = sample [0] [0] << shift;
*bptr++ = sample [1] [0] << shift;
}
else
i = 0; /* can't get here, but suppresses warning */
#ifdef ATTEMPT_ERROR_MUTING
if (!wps->wphdr.bits || (flags & WVC_FLAG)) {
int32_t *eptr = buffer + sample_count * ((flags & MONO_FLAG) ? 1 : 2);
for (bptr = buffer; bptr < eptr; bptr += 3)
if (*bptr > mute_limit || *bptr < -mute_limit) {
mute_block = 1;
break;
}
}
if (mute_block)
memset (buffer, 0, sizeof (*buffer) * sample_count * ((flags & MONO_FLAG) ? 1 : 2));
#endif
if (i && (wps->sample_index += i) == wpc->total_samples) {
if (wps->wphdr.version == 3 && crc != (wpc->wvc_flag ? wps->wphdr.crc2 : wps->wphdr.crc))
wpc->crc_errors++;
if (wpc->open_flags & OPEN_WRAPPER) {
unsigned char *temp = malloc (1024);
uint32_t bcount;
if (bs_unused_bytes (&wps->wvbits)) {
wpc->wrapper_data = realloc (wpc->wrapper_data, wpc->wrapper_bytes + bs_unused_bytes (&wps->wvbits));
memcpy (wpc->wrapper_data + wpc->wrapper_bytes, bs_unused_data (&wps->wvbits), bs_unused_bytes (&wps->wvbits));
wpc->wrapper_bytes += bs_unused_bytes (&wps->wvbits);
}
while (1) {
bcount = wpc->reader->read_bytes (wpc->wv_in, temp, 1024);
if (!bcount)
break;
wpc->wrapper_data = realloc (wpc->wrapper_data, wpc->wrapper_bytes + bcount);
memcpy (wpc->wrapper_data + wpc->wrapper_bytes, temp, bcount);
wpc->wrapper_bytes += bcount;
}
free (temp);
if (wpc->wrapper_bytes > 16) {
int c;
for (c = 0; c < 16 && wpc->wrapper_data [c] == 0xff; ++c);
if (c == 16) {
memmove (wpc->wrapper_data, wpc->wrapper_data + 16, wpc->wrapper_bytes - 16);
wpc->wrapper_bytes -= 16;
}
else {
free (wpc->wrapper_data);
wpc->wrapper_data = NULL;
wpc->wrapper_bytes = 0;
}
}
}
}
memcpy (wps->dc.sample, sample, sizeof (sample));
memcpy (wps->dc.weight, weight, sizeof (weight));
wps->dc.crc = crc;
wps->dc.m = m;
return i;
}
// This function initializes everything required to receive words with this
// module and must be called BEFORE any other function in this module.
static void init_words3 (WavpackStream3 *wps)
{
CLEAR (wps->w1);
CLEAR (wps->w2);
CLEAR (wps->w3);
CLEAR (wps->w4);
if (wps->wphdr.flags & MONO_FLAG)
wps->w4.bitrate = wps->wphdr.bits - 768;
else
wps->w4.bitrate = (wps->wphdr.bits / 2) - 768;
}
static int32_t FASTCALL get_word1 (WavpackStream3 *wps, int chan)
{
uint32_t tmp1, tmp2, avalue;
unsigned int ones_count;
int k;
if ((wps->wphdr.flags & EXTREME_DECORR) && !(wps->wphdr.flags & OVER_20)) {
if (wps->w1.zeros_acc) {
if (--wps->w1.zeros_acc)
return 0;
}
else if (wps->w1.ave_level [0] [0] < 0x20 && wps->w1.ave_level [0] [1] < 0x20) {
int32_t mask;
int cbits;
for (cbits = 0; cbits < 33 && getbit (&wps->wvbits); ++cbits);
if (cbits == 33)
return WORD_EOF;
if (cbits < 2)
wps->w1.zeros_acc = cbits;
else {
for (mask = 1, wps->w1.zeros_acc = 0; --cbits; mask <<= 1)
if (getbit (&wps->wvbits))
wps->w1.zeros_acc |= mask;
wps->w1.zeros_acc |= mask;
}
if (wps->w1.zeros_acc)
return 0;
}
}
// count consecutive ones in bitstream, > 25 indicates error (or EOF)
for (ones_count = 0; ones_count < 25 && getbit (&wps->wvbits); ++ones_count);
if (ones_count == 25)
return WORD_EOF;
k = (wps->w1.ave_level [0] [chan] + (wps->w1.ave_level [0] [chan] >> 3) + 0x40) >> 7;
k = count_bits (k);
if (k & ~31)
return WORD_EOF;
if (ones_count == 0) {
getbits (&avalue, k, &wps->wvbits);
avalue &= bitmask [k];
}
else {
tmp1 = bitset [k];
k = (wps->w1.ave_level [1] [chan] + (wps->w1.ave_level [1] [chan] >> 4) + 0x20) >> 6;
k = count_bits (k);
if (k & ~31)
return WORD_EOF;
if (ones_count == 1) {
getbits (&avalue, k, &wps->wvbits);
avalue &= bitmask [k];
}
else {
tmp2 = bitset [k];
// If the ones count is exactly 24, then next 24 bits are literal
if (ones_count == 24) {
getbits (&avalue, 24, &wps->wvbits);
avalue &= 0xffffff;
}
else {
k = (wps->w1.ave_level [2] [chan] + 0x10) >> 5;
k = count_bits (k);
if (k & ~31)
return WORD_EOF;
getbits (&avalue, k, &wps->wvbits);
avalue = (avalue & bitmask [k]) + (bitset [k] * (ones_count - 2));
}
wps->w1.ave_level [2] [chan] -= ((wps->w1.ave_level [2] [chan] + 0x8) >> 4);
wps->w1.ave_level [2] [chan] += avalue;
avalue += tmp2;
}
wps->w1.ave_level [1] [chan] -= ((wps->w1.ave_level [1] [chan] + 0x10) >> 5);
wps->w1.ave_level [1] [chan] += avalue;
avalue += tmp1;
}
wps->w1.ave_level [0] [chan] -= ((wps->w1.ave_level [0] [chan] + 0x20) >> 6);
wps->w1.ave_level [0] [chan] += avalue;
return (avalue && getbit (&wps->wvbits)) ? -(int32_t)avalue : avalue;
}
#define NUM_SAMPLES 128
static int32_t FASTCALL get_old_word1 (WavpackStream3 *wps, int chan)
{
uint32_t avalue;
unsigned int bc;
int k;
if (!wps->w1.index [chan]) {
int guess_k = (wps->w1.ave_k [chan] + 128) >> 8, ones;
for (ones = 0; ones < 72 && getbit (&wps->wvbits); ++ones);
if (ones == 72)
return WORD_EOF;
if (ones % 3 == 1)
wps->w1.k_value [chan] = guess_k - (ones / 3) - 1;
else
wps->w1.k_value [chan] = guess_k + ones - ((ones + 1) / 3);
wps->w1.ave_k [chan] -= (wps->w1.ave_k [chan] + 0x10) >> 5;
wps->w1.ave_k [chan] += wps->w1.k_value [chan] << 3;
}
if (++wps->w1.index [chan] == NUM_SAMPLES)
wps->w1.index [chan] = 0;
k = wps->w1.k_value [chan];
getbits (&avalue, k, &wps->wvbits);
for (bc = 0; bc < 32 && getbit (&wps->wvbits); ++bc);
if (bc == 32 || (k & ~31))
return WORD_EOF;
avalue = (avalue & bitmask [k]) + bitset [k] * bc;
return (avalue && getbit (&wps->wvbits)) ? -(int32_t)avalue : avalue;
}
static int32_t FASTCALL get_word2 (WavpackStream3 *wps, int chan)
{
int cbits, delta_dbits, dbits;
int32_t value, mask = 1;
cbits = 0;
while (getbit (&wps->wvbits))
if ((cbits += 2) == 50)
return WORD_EOF;
if (getbit (&wps->wvbits))
cbits++;
if (cbits == 0)
delta_dbits = 0;
else if (cbits & 1) {
delta_dbits = (cbits + 1) / 2;
if (wps->w2.last_delta_sign [chan] > 0)
delta_dbits *= -1;
wps->w2.last_delta_sign [chan] = delta_dbits;
}
else {
delta_dbits = cbits / 2;
if (wps->w2.last_delta_sign [chan] <= 0)
delta_dbits *= -1;
}
dbits = (wps->w2.last_dbits [chan] += delta_dbits);
if (dbits < 0 || dbits > 20)
return WORD_EOF;
if (!dbits)
return 0L;
if (wps->wphdr.bits) {
for (value = 1L << (dbits - 1); --dbits; mask <<= 1)
if (dbits < wps->wphdr.bits && getbit (&wps->wvbits))
value |= mask;
}
else
for (value = 1L << (dbits - 1); --dbits; mask <<= 1)
if (getbit (&wps->wvbits))
value |= mask;
return getbit (&wps->wvbits) ? -(int32_t)value : value;
}
static int32_t FASTCALL get_word3 (WavpackStream3 *wps, int chan)
{
int cbits, delta_dbits, dbits;
int32_t value;
for (cbits = 0; cbits < 72 && getbit (&wps->wvbits); ++cbits);
if (cbits == 72)
return WORD_EOF;
if (cbits || getbit (&wps->wvbits))
++cbits;
if (!((cbits + 1) % 3))
delta_dbits = (cbits + 1) / 3;
else
delta_dbits = -(cbits - cbits / 3);
if (chan) {
dbits = (wps->w3.ave_dbits [1] >> 8) + 1 + delta_dbits;
wps->w3.ave_dbits [1] -= (wps->w3.ave_dbits [1] + 0x10) >> 5;
wps->w3.ave_dbits [1] += dbits << 3;
}
else {
dbits = (wps->w3.ave_dbits [0] >> 8) + 1 + delta_dbits;
wps->w3.ave_dbits [0] -= (wps->w3.ave_dbits [0] + 0x10) >> 5;
wps->w3.ave_dbits [0] += dbits << 3;
}
if (dbits < 0 || dbits > 24)
return WORD_EOF;
if (!dbits)
return 0L;
if (wps->wphdr.bits && dbits > wps->wphdr.bits) {
getbits (&value, wps->wphdr.bits, &wps->wvbits);
if (value & bitset [wps->wphdr.bits - 1])
return -(int32_t)(value & bitmask [wps->wphdr.bits]) << (dbits - wps->wphdr.bits);
else
return ((value & bitmask [wps->wphdr.bits - 1]) | bitset [wps->wphdr.bits - 1]) << (dbits - wps->wphdr.bits);
}
else {
getbits (&value, dbits, &wps->wvbits);
if (value & bitset [dbits - 1])
return -(int32_t)(value & bitmask [dbits]);
else
return (value & bitmask [dbits - 1]) | bitset [dbits - 1];
}
}
static int FASTCALL wp3_log2 (uint32_t avalue);
static int32_t FASTCALL get_word4 (WavpackStream3 *wps, int chan, int32_t *correction)
{
uint32_t base, ones_count, avalue;
int32_t value, low, mid, high;
int bitcount;
// count consecutive ones in bitstream, > 25 indicates error (or EOF)
for (ones_count = 0; ones_count < 25 && getbit (&wps->wvbits); ++ones_count);
if (ones_count == 25)
return WORD_EOF;
// if the ones count is exactly 24, then we switch to non-unary method
if (ones_count == 24) {
int32_t mask;
int cbits;
for (cbits = 0; cbits < 33 && getbit (&wps->wvbits); ++cbits);
if (cbits == 33)
return WORD_EOF;
if (cbits < 2)
ones_count = cbits;
else {
for (mask = 1, ones_count = 0; --cbits; mask <<= 1)
if (getbit (&wps->wvbits))
ones_count |= mask;
ones_count |= mask;
}
ones_count += 24;
}
if (!chan) {
int slow_log_0, slow_log_1, balance;
if (wps->wphdr.flags & MONO_FLAG) {
wps->w4.bits_acc [0] += wps->w4.bitrate + wp3_log2 (wps->w4.fast_level [0]) - wp3_log2 (wps->w4.slow_level [0]) + (3 << 8);
if (wps->w4.bits_acc [0] < 0)
wps->w4.bits_acc [0] = 0;
}
else {
slow_log_0 = wp3_log2 (wps->w4.slow_level [0]);
slow_log_1 = wp3_log2 (wps->w4.slow_level [1]);
if (wps->wphdr.flags & JOINT_STEREO)
balance = (slow_log_1 - slow_log_0 + 257) >> 1;
else
balance = (slow_log_1 - slow_log_0 + 1) >> 1;
wps->w4.bits_acc [0] += wps->w4.bitrate - balance + wp3_log2 (wps->w4.fast_level [0]) - slow_log_0 + (3 << 8);
wps->w4.bits_acc [1] += wps->w4.bitrate + balance + wp3_log2 (wps->w4.fast_level [1]) - slow_log_1 + (3 << 8);
if (wps->w4.bits_acc [0] + wps->w4.bits_acc [1] < 0)
wps->w4.bits_acc [0] = wps->w4.bits_acc [1] = 0;
else if (wps->w4.bits_acc [0] < 0) {
wps->w4.bits_acc [1] += wps->w4.bits_acc [0];
wps->w4.bits_acc [0] = 0;
}
else if (wps->w4.bits_acc [1] < 0) {
wps->w4.bits_acc [0] += wps->w4.bits_acc [1];
wps->w4.bits_acc [1] = 0;
}
}
}
base = (wps->w4.fast_level [chan] + 48) / 96;
bitcount = wps->w4.bits_acc [chan] >> 8;
wps->w4.bits_acc [chan] &= 0xff;
if (!base) {
if (ones_count)
high = low = mid = (getbit (&wps->wvbits)) ? -(int32_t)ones_count : ones_count;
else
high = low = mid = 0;
}
else {
mid = (ones_count * 2 + 1) * base;
if (getbit (&wps->wvbits)) mid = -mid;
low = mid - base;
high = mid + base - 1;
while (bitcount--) {
if (getbit (&wps->wvbits))
mid = (high + (low = mid) + 1) >> 1;
else
mid = ((high = mid - 1) + low + 1) >> 1;
if (high == low)
break;
}
}
wps->w4.fast_level [chan] -= ((wps->w4.fast_level [chan] + 0x10) >> 5);
wps->w4.fast_level [chan] += (avalue = labs (mid));
wps->w4.slow_level [chan] -= ((wps->w4.slow_level [chan] + 0x80) >> 8);
wps->w4.slow_level [chan] += avalue;
if (bs_is_open (&wps->wvcbits)) {
if (high != low) {
uint32_t maxcode = high - low;
int bitcount = count_bits (maxcode);
uint32_t extras = (1L << bitcount) - maxcode - 1;
getbits (&avalue, bitcount - 1, &wps->wvcbits);
avalue &= bitmask [bitcount - 1];
if (avalue >= extras) {
avalue = (avalue << 1) - extras;
if (getbit (&wps->wvcbits))
++avalue;
}
value = (mid < 0) ? high - avalue : avalue + low;
if (correction)
*correction = value - mid;
}
else if (correction)
*correction = 0;
}
return mid;
}
// This function calculates an approximate base-2 logarithm (with 8 bits of
// fraction) from the supplied value. Using logarithms makes comparing
// signal level values and calculating fractional bitrates much easier.
static int FASTCALL wp3_log2 (uint32_t avalue)
{
int dbits;
if ((avalue += avalue >> 9) < (1 << 8)) {
dbits = nbits_table [avalue];
return (dbits << 8) + ((avalue << (9 - dbits)) & 0xff);
}
else {
if (avalue < (1L << 16))
dbits = nbits_table [avalue >> 8] + 8;
else if (avalue < (1L << 24))
dbits = nbits_table [avalue >> 16] + 16;
else
dbits = nbits_table [avalue >> 24] + 24;
return (dbits << 8) + ((avalue >> (dbits - 9)) & 0xff);
}
}
static void bs_read3 (Bitstream3 *bs)
{
uint32_t bytes_read;
bytes_read = bs->reader->read_bytes (bs->id, bs->buf, bs->bufsiz);
bs->end = bs->buf + bytes_read;
bs->fpos += bytes_read;
if (bs->end == bs->buf) {
memset (bs->buf, -1, bs->bufsiz);
bs->end += bs->bufsiz;
}
bs->ptr = bs->buf;
}
// Open the specified BitStream and associate with the specified file. The
// "bufsiz" field of the structure must be preset with the desired buffer
// size and the file's read pointer must be set to where the desired bit
// data is located. A return value of TRUE indicates an error in
// allocating buffer space.
static int bs_open_read3 (Bitstream3 *bs, WavpackStreamReader64 *reader, void *id)
{
bs->fpos = (bs->reader = reader)->get_pos (bs->id = id);
if (!bs->buf)
bs->buf = (unsigned char *) malloc (bs->bufsiz);
bs->end = bs->buf + bs->bufsiz;
bs->ptr = bs->end - 1;
bs->sr = bs->bc = 0;
bs->error = bs->buf ? 0 : 1;
bs->wrap = bs_read3;
return bs->error;
}
static uint32_t bs_unused_bytes (Bitstream3 *bs)
{
if (bs->bc < 8) {
bs->bc += 8;
bs->ptr++;
}
return (uint32_t)(bs->end - bs->ptr);
}
static unsigned char *bs_unused_data (Bitstream3 *bs)
{
if (bs->bc < 8) {
bs->bc += 8;
bs->ptr++;
}
return bs->ptr;
}