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FFmpeg/libavcodec/wavpack.c
Michael Niedermayer 874c5b02c4 Merge commit '594d4d5df3c70404168701dd5c90b7e6e5587793' 
* commit '594d4d5df3c70404168701dd5c90b7e6e5587793':
  lavc: add a wrapper for AVCodecContext.get_buffer().

Conflicts:
	libavcodec/4xm.c
	libavcodec/8svx.c
	libavcodec/bmv.c
	libavcodec/cljr.c
	libavcodec/cscd.c
	libavcodec/dnxhddec.c
	libavcodec/dpcm.c
	libavcodec/dpx.c
	libavcodec/eacmv.c
	libavcodec/eamad.c
	libavcodec/frwu.c
	libavcodec/g723_1.c
	libavcodec/gifdec.c
	libavcodec/idcinvideo.c
	libavcodec/iff.c
	libavcodec/indeo3.c
	libavcodec/internal.h
	libavcodec/interplayvideo.c
	libavcodec/kmvc.c
	libavcodec/mpc7.c
	libavcodec/mpegaudiodec.c
	libavcodec/pcx.c
	libavcodec/pngdec.c
	libavcodec/pnmdec.c
	libavcodec/rl2.c
	libavcodec/snow.c
	libavcodec/targa.c
	libavcodec/tscc.c
	libavcodec/txd.c
	libavcodec/utils.c
	libavcodec/v210dec.c
	libavcodec/vb.c
	libavcodec/vmdav.c
	libavcodec/vp56.c
	libavcodec/vqavideo.c
	libavcodec/wavpack.c
	libavcodec/wnv1.c
	libavcodec/xl.c
	libavcodec/yop.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>
2012-12-05 15:18:12 +01:00

1274 lines
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/*
* WavPack lossless audio decoder
* Copyright (c) 2006,2011 Konstantin Shishkov
*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#define BITSTREAM_READER_LE
#include "libavutil/channel_layout.h"
#include "avcodec.h"
#include "get_bits.h"
#include "internal.h"
#include "unary.h"
/**
* @file
* WavPack lossless audio decoder
*/
#define WV_MONO 0x00000004
#define WV_JOINT_STEREO 0x00000010
#define WV_FALSE_STEREO 0x40000000
#define WV_HYBRID_MODE 0x00000008
#define WV_HYBRID_SHAPE 0x00000008
#define WV_HYBRID_BITRATE 0x00000200
#define WV_HYBRID_BALANCE 0x00000400
#define WV_FLT_SHIFT_ONES 0x01
#define WV_FLT_SHIFT_SAME 0x02
#define WV_FLT_SHIFT_SENT 0x04
#define WV_FLT_ZERO_SENT 0x08
#define WV_FLT_ZERO_SIGN 0x10
#define WV_MAX_SAMPLES 131072
enum WP_ID_Flags {
WP_IDF_MASK = 0x1F,
WP_IDF_IGNORE = 0x20,
WP_IDF_ODD = 0x40,
WP_IDF_LONG = 0x80
};
enum WP_ID {
WP_ID_DUMMY = 0,
WP_ID_ENCINFO,
WP_ID_DECTERMS,
WP_ID_DECWEIGHTS,
WP_ID_DECSAMPLES,
WP_ID_ENTROPY,
WP_ID_HYBRID,
WP_ID_SHAPING,
WP_ID_FLOATINFO,
WP_ID_INT32INFO,
WP_ID_DATA,
WP_ID_CORR,
WP_ID_EXTRABITS,
WP_ID_CHANINFO
};
typedef struct SavedContext {
int offset;
int size;
int bits_used;
uint32_t crc;
} SavedContext;
#define MAX_TERMS 16
typedef struct Decorr {
int delta;
int value;
int weightA;
int weightB;
int samplesA[8];
int samplesB[8];
} Decorr;
typedef struct WvChannel {
int median[3];
int slow_level, error_limit;
int bitrate_acc, bitrate_delta;
} WvChannel;
typedef struct WavpackFrameContext {
AVCodecContext *avctx;
int frame_flags;
int stereo, stereo_in;
int joint;
uint32_t CRC;
GetBitContext gb;
int got_extra_bits;
uint32_t crc_extra_bits;
GetBitContext gb_extra_bits;
int data_size; // in bits
int samples;
int terms;
Decorr decorr[MAX_TERMS];
int zero, one, zeroes;
int extra_bits;
int and, or, shift;
int post_shift;
int hybrid, hybrid_bitrate;
int hybrid_maxclip, hybrid_minclip;
int float_flag;
int float_shift;
int float_max_exp;
WvChannel ch[2];
int pos;
SavedContext sc, extra_sc;
} WavpackFrameContext;
#define WV_MAX_FRAME_DECODERS 14
typedef struct WavpackContext {
AVCodecContext *avctx;
AVFrame frame;
WavpackFrameContext *fdec[WV_MAX_FRAME_DECODERS];
int fdec_num;
int multichannel;
int mkv_mode;
int block;
int samples;
int ch_offset;
} WavpackContext;
// exponent table copied from WavPack source
static const uint8_t wp_exp2_table [256] = {
0x00, 0x01, 0x01, 0x02, 0x03, 0x03, 0x04, 0x05, 0x06, 0x06, 0x07, 0x08, 0x08, 0x09, 0x0a, 0x0b,
0x0b, 0x0c, 0x0d, 0x0e, 0x0e, 0x0f, 0x10, 0x10, 0x11, 0x12, 0x13, 0x13, 0x14, 0x15, 0x16, 0x16,
0x17, 0x18, 0x19, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1d, 0x1e, 0x1f, 0x20, 0x20, 0x21, 0x22, 0x23,
0x24, 0x24, 0x25, 0x26, 0x27, 0x28, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2c, 0x2d, 0x2e, 0x2f, 0x30,
0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3a, 0x3b, 0x3c, 0x3d,
0x3e, 0x3f, 0x40, 0x41, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x48, 0x49, 0x4a, 0x4b,
0x4c, 0x4d, 0x4e, 0x4f, 0x50, 0x51, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a,
0x5b, 0x5c, 0x5d, 0x5e, 0x5e, 0x5f, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,
0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79,
0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x87, 0x88, 0x89, 0x8a,
0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0x90, 0x91, 0x92, 0x93, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0x9b,
0x9c, 0x9d, 0x9f, 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad,
0xaf, 0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xbc, 0xbd, 0xbe, 0xbf, 0xc0,
0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc8, 0xc9, 0xca, 0xcb, 0xcd, 0xce, 0xcf, 0xd0, 0xd2, 0xd3, 0xd4,
0xd6, 0xd7, 0xd8, 0xd9, 0xdb, 0xdc, 0xdd, 0xde, 0xe0, 0xe1, 0xe2, 0xe4, 0xe5, 0xe6, 0xe8, 0xe9,
0xea, 0xec, 0xed, 0xee, 0xf0, 0xf1, 0xf2, 0xf4, 0xf5, 0xf6, 0xf8, 0xf9, 0xfa, 0xfc, 0xfd, 0xff
};
static const uint8_t wp_log2_table [] = {
0x00, 0x01, 0x03, 0x04, 0x06, 0x07, 0x09, 0x0a, 0x0b, 0x0d, 0x0e, 0x10, 0x11, 0x12, 0x14, 0x15,
0x16, 0x18, 0x19, 0x1a, 0x1c, 0x1d, 0x1e, 0x20, 0x21, 0x22, 0x24, 0x25, 0x26, 0x28, 0x29, 0x2a,
0x2c, 0x2d, 0x2e, 0x2f, 0x31, 0x32, 0x33, 0x34, 0x36, 0x37, 0x38, 0x39, 0x3b, 0x3c, 0x3d, 0x3e,
0x3f, 0x41, 0x42, 0x43, 0x44, 0x45, 0x47, 0x48, 0x49, 0x4a, 0x4b, 0x4d, 0x4e, 0x4f, 0x50, 0x51,
0x52, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x5c, 0x5d, 0x5e, 0x5f, 0x60, 0x61, 0x62, 0x63,
0x64, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72, 0x74, 0x75,
0x76, 0x77, 0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85,
0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95,
0x96, 0x97, 0x98, 0x99, 0x9a, 0x9b, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, 0xa0, 0xa1, 0xa2, 0xa3, 0xa4,
0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, 0xb0, 0xb1, 0xb2, 0xb2,
0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, 0xc0, 0xc0,
0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xcb, 0xcb, 0xcc, 0xcd, 0xce,
0xcf, 0xd0, 0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd8, 0xd9, 0xda, 0xdb,
0xdc, 0xdc, 0xdd, 0xde, 0xdf, 0xe0, 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe4, 0xe5, 0xe6, 0xe7, 0xe7,
0xe8, 0xe9, 0xea, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xee, 0xef, 0xf0, 0xf1, 0xf1, 0xf2, 0xf3, 0xf4,
0xf4, 0xf5, 0xf6, 0xf7, 0xf7, 0xf8, 0xf9, 0xf9, 0xfa, 0xfb, 0xfc, 0xfc, 0xfd, 0xfe, 0xff, 0xff
};
static av_always_inline int wp_exp2(int16_t val)
{
int res, neg = 0;
if (val < 0) {
val = -val;
neg = 1;
}
res = wp_exp2_table[val & 0xFF] | 0x100;
val >>= 8;
res = (val > 9) ? (res << (val - 9)) : (res >> (9 - val));
return neg ? -res : res;
}
static av_always_inline int wp_log2(int32_t val)
{
int bits;
if (!val)
return 0;
if (val == 1)
return 256;
val += val >> 9;
bits = av_log2(val) + 1;
if (bits < 9)
return (bits << 8) + wp_log2_table[(val << (9 - bits)) & 0xFF];
else
return (bits << 8) + wp_log2_table[(val >> (bits - 9)) & 0xFF];
}
#define LEVEL_DECAY(a) ((a + 0x80) >> 8)
// macros for manipulating median values
#define GET_MED(n) ((c->median[n] >> 4) + 1)
#define DEC_MED(n) c->median[n] -= ((c->median[n] + (128 >> n) - 2) / (128 >> n)) * 2
#define INC_MED(n) c->median[n] += ((c->median[n] + (128 >> n) ) / (128 >> n)) * 5
// macros for applying weight
#define UPDATE_WEIGHT_CLIP(weight, delta, samples, in) \
if (samples && in) { \
if ((samples ^ in) < 0) { \
weight -= delta; \
if (weight < -1024) \
weight = -1024; \
} else { \
weight += delta; \
if (weight > 1024) \
weight = 1024; \
} \
}
static av_always_inline int get_tail(GetBitContext *gb, int k)
{
int p, e, res;
if (k < 1)
return 0;
p = av_log2(k);
e = (1 << (p + 1)) - k - 1;
res = p ? get_bits(gb, p) : 0;
if (res >= e)
res = (res << 1) - e + get_bits1(gb);
return res;
}
static void update_error_limit(WavpackFrameContext *ctx)
{
int i, br[2], sl[2];
for (i = 0; i <= ctx->stereo_in; i++) {
ctx->ch[i].bitrate_acc += ctx->ch[i].bitrate_delta;
br[i] = ctx->ch[i].bitrate_acc >> 16;
sl[i] = LEVEL_DECAY(ctx->ch[i].slow_level);
}
if (ctx->stereo_in && ctx->hybrid_bitrate) {
int balance = (sl[1] - sl[0] + br[1] + 1) >> 1;
if (balance > br[0]) {
br[1] = br[0] << 1;
br[0] = 0;
} else if (-balance > br[0]) {
br[0] <<= 1;
br[1] = 0;
} else {
br[1] = br[0] + balance;
br[0] = br[0] - balance;
}
}
for (i = 0; i <= ctx->stereo_in; i++) {
if (ctx->hybrid_bitrate) {
if (sl[i] - br[i] > -0x100)
ctx->ch[i].error_limit = wp_exp2(sl[i] - br[i] + 0x100);
else
ctx->ch[i].error_limit = 0;
} else {
ctx->ch[i].error_limit = wp_exp2(br[i]);
}
}
}
static int wv_get_value(WavpackFrameContext *ctx, GetBitContext *gb,
int channel, int *last)
{
int t, t2;
int sign, base, add, ret;
WvChannel *c = &ctx->ch[channel];
*last = 0;
if ((ctx->ch[0].median[0] < 2U) && (ctx->ch[1].median[0] < 2U) &&
!ctx->zero && !ctx->one) {
if (ctx->zeroes) {
ctx->zeroes--;
if (ctx->zeroes) {
c->slow_level -= LEVEL_DECAY(c->slow_level);
return 0;
}
} else {
t = get_unary_0_33(gb);
if (t >= 2) {
if (get_bits_left(gb) < t - 1)
goto error;
t = get_bits(gb, t - 1) | (1 << (t-1));
} else {
if (get_bits_left(gb) < 0)
goto error;
}
ctx->zeroes = t;
if (ctx->zeroes) {
memset(ctx->ch[0].median, 0, sizeof(ctx->ch[0].median));
memset(ctx->ch[1].median, 0, sizeof(ctx->ch[1].median));
c->slow_level -= LEVEL_DECAY(c->slow_level);
return 0;
}
}
}
if (ctx->zero) {
t = 0;
ctx->zero = 0;
} else {
t = get_unary_0_33(gb);
if (get_bits_left(gb) < 0)
goto error;
if (t == 16) {
t2 = get_unary_0_33(gb);
if (t2 < 2) {
if (get_bits_left(gb) < 0)
goto error;
t += t2;
} else {
if (get_bits_left(gb) < t2 - 1)
goto error;
t += get_bits(gb, t2 - 1) | (1 << (t2 - 1));
}
}
if (ctx->one) {
ctx->one = t & 1;
t = (t >> 1) + 1;
} else {
ctx->one = t & 1;
t >>= 1;
}
ctx->zero = !ctx->one;
}
if (ctx->hybrid && !channel)
update_error_limit(ctx);
if (!t) {
base = 0;
add = GET_MED(0) - 1;
DEC_MED(0);
} else if (t == 1) {
base = GET_MED(0);
add = GET_MED(1) - 1;
INC_MED(0);
DEC_MED(1);
} else if (t == 2) {
base = GET_MED(0) + GET_MED(1);
add = GET_MED(2) - 1;
INC_MED(0);
INC_MED(1);
DEC_MED(2);
} else {
base = GET_MED(0) + GET_MED(1) + GET_MED(2) * (t - 2);
add = GET_MED(2) - 1;
INC_MED(0);
INC_MED(1);
INC_MED(2);
}
if (!c->error_limit) {
ret = base + get_tail(gb, add);
if (get_bits_left(gb) <= 0)
goto error;
} else {
int mid = (base * 2 + add + 1) >> 1;
while (add > c->error_limit) {
if (get_bits_left(gb) <= 0)
goto error;
if (get_bits1(gb)) {
add -= (mid - base);
base = mid;
} else
add = mid - base - 1;
mid = (base * 2 + add + 1) >> 1;
}
ret = mid;
}
sign = get_bits1(gb);
if (ctx->hybrid_bitrate)
c->slow_level += wp_log2(ret) - LEVEL_DECAY(c->slow_level);
return sign ? ~ret : ret;
error:
*last = 1;
return 0;
}
static inline int wv_get_value_integer(WavpackFrameContext *s, uint32_t *crc,
int S)
{
int bit;
if (s->extra_bits){
S <<= s->extra_bits;
if (s->got_extra_bits && get_bits_left(&s->gb_extra_bits) >= s->extra_bits) {
S |= get_bits(&s->gb_extra_bits, s->extra_bits);
*crc = *crc * 9 + (S & 0xffff) * 3 + ((unsigned)S >> 16);
}
}
bit = (S & s->and) | s->or;
bit = ((S + bit) << s->shift) - bit;
if (s->hybrid)
bit = av_clip(bit, s->hybrid_minclip, s->hybrid_maxclip);
return bit << s->post_shift;
}
static float wv_get_value_float(WavpackFrameContext *s, uint32_t *crc, int S)
{
union {
float f;
uint32_t u;
} value;
unsigned int sign;
int exp = s->float_max_exp;
if (s->got_extra_bits) {
const int max_bits = 1 + 23 + 8 + 1;
const int left_bits = get_bits_left(&s->gb_extra_bits);
if (left_bits + 8 * FF_INPUT_BUFFER_PADDING_SIZE < max_bits)
return 0.0;
}
if (S) {
S <<= s->float_shift;
sign = S < 0;
if (sign)
S = -S;
if (S >= 0x1000000) {
if (s->got_extra_bits && get_bits1(&s->gb_extra_bits))
S = get_bits(&s->gb_extra_bits, 23);
else
S = 0;
exp = 255;
} else if (exp) {
int shift = 23 - av_log2(S);
exp = s->float_max_exp;
if (exp <= shift)
shift = --exp;
exp -= shift;
if (shift) {
S <<= shift;
if ((s->float_flag & WV_FLT_SHIFT_ONES) ||
(s->got_extra_bits && (s->float_flag & WV_FLT_SHIFT_SAME) &&
get_bits1(&s->gb_extra_bits))) {
S |= (1 << shift) - 1;
} else if (s->got_extra_bits &&
(s->float_flag & WV_FLT_SHIFT_SENT)) {
S |= get_bits(&s->gb_extra_bits, shift);
}
}
} else {
exp = s->float_max_exp;
}
S &= 0x7fffff;
} else {
sign = 0;
exp = 0;
if (s->got_extra_bits && (s->float_flag & WV_FLT_ZERO_SENT)) {
if (get_bits1(&s->gb_extra_bits)) {
S = get_bits(&s->gb_extra_bits, 23);
if (s->float_max_exp >= 25)
exp = get_bits(&s->gb_extra_bits, 8);
sign = get_bits1(&s->gb_extra_bits);
} else {
if (s->float_flag & WV_FLT_ZERO_SIGN)
sign = get_bits1(&s->gb_extra_bits);
}
}
}
*crc = *crc * 27 + S * 9 + exp * 3 + sign;
value.u = (sign << 31) | (exp << 23) | S;
return value.f;
}
static void wv_reset_saved_context(WavpackFrameContext *s)
{
s->pos = 0;
s->sc.crc = s->extra_sc.crc = 0xFFFFFFFF;
}
static inline int wv_check_crc(WavpackFrameContext *s, uint32_t crc,
uint32_t crc_extra_bits)
{
if (crc != s->CRC) {
av_log(s->avctx, AV_LOG_ERROR, "CRC error\n");
return AVERROR_INVALIDDATA;
}
if (s->got_extra_bits && crc_extra_bits != s->crc_extra_bits) {
av_log(s->avctx, AV_LOG_ERROR, "Extra bits CRC error\n");
return AVERROR_INVALIDDATA;
}
return 0;
}
static inline int wv_unpack_stereo(WavpackFrameContext *s, GetBitContext *gb,
void *dst, const int type)
{
int i, j, count = 0;
int last, t;
int A, B, L, L2, R, R2;
int pos = s->pos;
uint32_t crc = s->sc.crc;
uint32_t crc_extra_bits = s->extra_sc.crc;
int16_t *dst16 = dst;
int32_t *dst32 = dst;
float *dstfl = dst;
const int channel_pad = s->avctx->channels - 2;
s->one = s->zero = s->zeroes = 0;
do {
L = wv_get_value(s, gb, 0, &last);
if (last)
break;
R = wv_get_value(s, gb, 1, &last);
if (last)
break;
for (i = 0; i < s->terms; i++) {
t = s->decorr[i].value;
if (t > 0) {
if (t > 8) {
if (t & 1) {
A = 2 * s->decorr[i].samplesA[0] - s->decorr[i].samplesA[1];
B = 2 * s->decorr[i].samplesB[0] - s->decorr[i].samplesB[1];
} else {
A = (3 * s->decorr[i].samplesA[0] - s->decorr[i].samplesA[1]) >> 1;
B = (3 * s->decorr[i].samplesB[0] - s->decorr[i].samplesB[1]) >> 1;
}
s->decorr[i].samplesA[1] = s->decorr[i].samplesA[0];
s->decorr[i].samplesB[1] = s->decorr[i].samplesB[0];
j = 0;
} else {
A = s->decorr[i].samplesA[pos];
B = s->decorr[i].samplesB[pos];
j = (pos + t) & 7;
}
if (type != AV_SAMPLE_FMT_S16) {
L2 = L + ((s->decorr[i].weightA * (int64_t)A + 512) >> 10);
R2 = R + ((s->decorr[i].weightB * (int64_t)B + 512) >> 10);
} else {
L2 = L + ((s->decorr[i].weightA * A + 512) >> 10);
R2 = R + ((s->decorr[i].weightB * B + 512) >> 10);
}
if (A && L) s->decorr[i].weightA -= ((((L ^ A) >> 30) & 2) - 1) * s->decorr[i].delta;
if (B && R) s->decorr[i].weightB -= ((((R ^ B) >> 30) & 2) - 1) * s->decorr[i].delta;
s->decorr[i].samplesA[j] = L = L2;
s->decorr[i].samplesB[j] = R = R2;
} else if (t == -1) {
if (type != AV_SAMPLE_FMT_S16)
L2 = L + ((s->decorr[i].weightA * (int64_t)s->decorr[i].samplesA[0] + 512) >> 10);
else
L2 = L + ((s->decorr[i].weightA * s->decorr[i].samplesA[0] + 512) >> 10);
UPDATE_WEIGHT_CLIP(s->decorr[i].weightA, s->decorr[i].delta, s->decorr[i].samplesA[0], L);
L = L2;
if (type != AV_SAMPLE_FMT_S16)
R2 = R + ((s->decorr[i].weightB * (int64_t)L2 + 512) >> 10);
else
R2 = R + ((s->decorr[i].weightB * L2 + 512) >> 10);
UPDATE_WEIGHT_CLIP(s->decorr[i].weightB, s->decorr[i].delta, L2, R);
R = R2;
s->decorr[i].samplesA[0] = R;
} else {
if (type != AV_SAMPLE_FMT_S16)
R2 = R + ((s->decorr[i].weightB * (int64_t)s->decorr[i].samplesB[0] + 512) >> 10);
else
R2 = R + ((s->decorr[i].weightB * s->decorr[i].samplesB[0] + 512) >> 10);
UPDATE_WEIGHT_CLIP(s->decorr[i].weightB, s->decorr[i].delta, s->decorr[i].samplesB[0], R);
R = R2;
if (t == -3) {
R2 = s->decorr[i].samplesA[0];
s->decorr[i].samplesA[0] = R;
}
if (type != AV_SAMPLE_FMT_S16)
L2 = L + ((s->decorr[i].weightA * (int64_t)R2 + 512) >> 10);
else
L2 = L + ((s->decorr[i].weightA * R2 + 512) >> 10);
UPDATE_WEIGHT_CLIP(s->decorr[i].weightA, s->decorr[i].delta, R2, L);
L = L2;
s->decorr[i].samplesB[0] = L;
}
}
pos = (pos + 1) & 7;
if (s->joint)
L += (R -= (L >> 1));
crc = (crc * 3 + L) * 3 + R;
if (type == AV_SAMPLE_FMT_FLT) {
*dstfl++ = wv_get_value_float(s, &crc_extra_bits, L);
*dstfl++ = wv_get_value_float(s, &crc_extra_bits, R);
dstfl += channel_pad;
} else if (type == AV_SAMPLE_FMT_S32) {
*dst32++ = wv_get_value_integer(s, &crc_extra_bits, L);
*dst32++ = wv_get_value_integer(s, &crc_extra_bits, R);
dst32 += channel_pad;
} else {
*dst16++ = wv_get_value_integer(s, &crc_extra_bits, L);
*dst16++ = wv_get_value_integer(s, &crc_extra_bits, R);
dst16 += channel_pad;
}
count++;
} while (!last && count < s->samples);
wv_reset_saved_context(s);
if ((s->avctx->err_recognition & AV_EF_CRCCHECK) &&
wv_check_crc(s, crc, crc_extra_bits))
return AVERROR_INVALIDDATA;
return count * 2;
}
static inline int wv_unpack_mono(WavpackFrameContext *s, GetBitContext *gb,
void *dst, const int type)
{
int i, j, count = 0;
int last, t;
int A, S, T;
int pos = s->pos;
uint32_t crc = s->sc.crc;
uint32_t crc_extra_bits = s->extra_sc.crc;
int16_t *dst16 = dst;
int32_t *dst32 = dst;
float *dstfl = dst;
const int channel_stride = s->avctx->channels;
s->one = s->zero = s->zeroes = 0;
do {
T = wv_get_value(s, gb, 0, &last);
S = 0;
if (last)
break;
for (i = 0; i < s->terms; i++) {
t = s->decorr[i].value;
if (t > 8) {
if (t & 1)
A = 2 * s->decorr[i].samplesA[0] - s->decorr[i].samplesA[1];
else
A = (3 * s->decorr[i].samplesA[0] - s->decorr[i].samplesA[1]) >> 1;
s->decorr[i].samplesA[1] = s->decorr[i].samplesA[0];
j = 0;
} else {
A = s->decorr[i].samplesA[pos];
j = (pos + t) & 7;
}
if (type != AV_SAMPLE_FMT_S16)
S = T + ((s->decorr[i].weightA * (int64_t)A + 512) >> 10);
else
S = T + ((s->decorr[i].weightA * A + 512) >> 10);
if (A && T)
s->decorr[i].weightA -= ((((T ^ A) >> 30) & 2) - 1) * s->decorr[i].delta;
s->decorr[i].samplesA[j] = T = S;
}
pos = (pos + 1) & 7;
crc = crc * 3 + S;
if (type == AV_SAMPLE_FMT_FLT) {
*dstfl = wv_get_value_float(s, &crc_extra_bits, S);
dstfl += channel_stride;
} else if (type == AV_SAMPLE_FMT_S32) {
*dst32 = wv_get_value_integer(s, &crc_extra_bits, S);
dst32 += channel_stride;
} else {
*dst16 = wv_get_value_integer(s, &crc_extra_bits, S);
dst16 += channel_stride;
}
count++;
} while (!last && count < s->samples);
wv_reset_saved_context(s);
if ((s->avctx->err_recognition & AV_EF_CRCCHECK) &&
wv_check_crc(s, crc, crc_extra_bits))
return AVERROR_INVALIDDATA;
return count;
}
static av_cold int wv_alloc_frame_context(WavpackContext *c)
{
if (c->fdec_num == WV_MAX_FRAME_DECODERS)
return -1;
c->fdec[c->fdec_num] = av_mallocz(sizeof(**c->fdec));
if (!c->fdec[c->fdec_num])
return -1;
c->fdec_num++;
c->fdec[c->fdec_num - 1]->avctx = c->avctx;
wv_reset_saved_context(c->fdec[c->fdec_num - 1]);
return 0;
}
static av_cold int wavpack_decode_init(AVCodecContext *avctx)
{
WavpackContext *s = avctx->priv_data;
s->avctx = avctx;
if (avctx->bits_per_coded_sample <= 16)
avctx->sample_fmt = AV_SAMPLE_FMT_S16;
else
avctx->sample_fmt = AV_SAMPLE_FMT_S32;
if (avctx->channels <= 2 && !avctx->channel_layout)
avctx->channel_layout = (avctx->channels == 2) ? AV_CH_LAYOUT_STEREO :
AV_CH_LAYOUT_MONO;
s->multichannel = avctx->channels > 2;
/* lavf demuxer does not provide extradata, Matroska stores 0x403
there, use this to detect decoding mode for multichannel */
s->mkv_mode = 0;
if (s->multichannel && avctx->extradata && avctx->extradata_size == 2) {
int ver = AV_RL16(avctx->extradata);
if (ver >= 0x402 && ver <= 0x410)
s->mkv_mode = 1;
}
s->fdec_num = 0;
avcodec_get_frame_defaults(&s->frame);
avctx->coded_frame = &s->frame;
return 0;
}
static av_cold int wavpack_decode_end(AVCodecContext *avctx)
{
WavpackContext *s = avctx->priv_data;
int i;
for (i = 0; i < s->fdec_num; i++)
av_freep(&s->fdec[i]);
s->fdec_num = 0;
return 0;
}
static int wavpack_decode_block(AVCodecContext *avctx, int block_no,
void *data, int *got_frame_ptr,
const uint8_t *buf, int buf_size)
{
WavpackContext *wc = avctx->priv_data;
WavpackFrameContext *s;
void *samples = data;
int samplecount;
int got_terms = 0, got_weights = 0, got_samples = 0,
got_entropy = 0, got_bs = 0, got_float = 0, got_hybrid = 0;
const uint8_t *orig_buf = buf;
const uint8_t *buf_end = buf + buf_size;
int i, j, id, size, ssize, weights, t;
int bpp, chan, chmask, orig_bpp;
if (buf_size == 0) {
*got_frame_ptr = 0;
return 0;
}
if (block_no >= wc->fdec_num && wv_alloc_frame_context(wc) < 0) {
av_log(avctx, AV_LOG_ERROR, "Error creating frame decode context\n");
return -1;
}
s = wc->fdec[block_no];
if (!s) {
av_log(avctx, AV_LOG_ERROR, "Context for block %d is not present\n", block_no);
return -1;
}
if (wc->ch_offset >= avctx->channels) {
av_log(avctx, AV_LOG_ERROR, "too many channels\n");
return -1;
}
memset(s->decorr, 0, MAX_TERMS * sizeof(Decorr));
memset(s->ch, 0, sizeof(s->ch));
s->extra_bits = 0;
s->and = s->or = s->shift = 0;
s->got_extra_bits = 0;
if (!wc->mkv_mode) {
s->samples = AV_RL32(buf); buf += 4;
if (!s->samples) {
*got_frame_ptr = 0;
return 0;
}
if (s->samples > wc->samples) {
av_log(avctx, AV_LOG_ERROR, "too many samples in block");
return -1;
}
} else {
s->samples = wc->samples;
}
s->frame_flags = AV_RL32(buf); buf += 4;
bpp = av_get_bytes_per_sample(avctx->sample_fmt);
samples = (uint8_t*)samples + bpp * wc->ch_offset;
orig_bpp = ((s->frame_flags & 0x03) + 1) << 3;
s->stereo = !(s->frame_flags & WV_MONO);
s->stereo_in = (s->frame_flags & WV_FALSE_STEREO) ? 0 : s->stereo;
s->joint = s->frame_flags & WV_JOINT_STEREO;
s->hybrid = s->frame_flags & WV_HYBRID_MODE;
s->hybrid_bitrate = s->frame_flags & WV_HYBRID_BITRATE;
s->post_shift = bpp * 8 - orig_bpp + ((s->frame_flags >> 13) & 0x1f);
s->hybrid_maxclip = (( 1LL << (orig_bpp - 1)) - 1);
s->hybrid_minclip = ((-1LL << (orig_bpp - 1)));
s->CRC = AV_RL32(buf); buf += 4;
if (wc->mkv_mode)
buf += 4; //skip block size;
wc->ch_offset += 1 + s->stereo;
// parse metadata blocks
while (buf < buf_end) {
id = *buf++;
size = *buf++;
if (id & WP_IDF_LONG) {
size |= (*buf++) << 8;
size |= (*buf++) << 16;
}
size <<= 1; // size is specified in words
ssize = size;
if (id & WP_IDF_ODD)
size--;
if (size < 0) {
av_log(avctx, AV_LOG_ERROR, "Got incorrect block %02X with size %i\n", id, size);
break;
}
if (buf + ssize > buf_end) {
av_log(avctx, AV_LOG_ERROR, "Block size %i is out of bounds\n", size);
break;
}
if (id & WP_IDF_IGNORE) {
buf += ssize;
continue;
}
switch (id & WP_IDF_MASK) {
case WP_ID_DECTERMS:
if (size > MAX_TERMS) {
av_log(avctx, AV_LOG_ERROR, "Too many decorrelation terms\n");
s->terms = 0;
buf += ssize;
continue;
}
s->terms = size;
for (i = 0; i < s->terms; i++) {
s->decorr[s->terms - i - 1].value = (*buf & 0x1F) - 5;
s->decorr[s->terms - i - 1].delta = *buf >> 5;
buf++;
}
got_terms = 1;
break;
case WP_ID_DECWEIGHTS:
if (!got_terms) {
av_log(avctx, AV_LOG_ERROR, "No decorrelation terms met\n");
continue;
}
weights = size >> s->stereo_in;
if (weights > MAX_TERMS || weights > s->terms) {
av_log(avctx, AV_LOG_ERROR, "Too many decorrelation weights\n");
buf += ssize;
continue;
}
for (i = 0; i < weights; i++) {
t = (int8_t)(*buf++);
s->decorr[s->terms - i - 1].weightA = t << 3;
if (s->decorr[s->terms - i - 1].weightA > 0)
s->decorr[s->terms - i - 1].weightA +=
(s->decorr[s->terms - i - 1].weightA + 64) >> 7;
if (s->stereo_in) {
t = (int8_t)(*buf++);
s->decorr[s->terms - i - 1].weightB = t << 3;
if (s->decorr[s->terms - i - 1].weightB > 0)
s->decorr[s->terms - i - 1].weightB +=
(s->decorr[s->terms - i - 1].weightB + 64) >> 7;
}
}
got_weights = 1;
break;
case WP_ID_DECSAMPLES:
if (!got_terms) {
av_log(avctx, AV_LOG_ERROR, "No decorrelation terms met\n");
continue;
}
t = 0;
for (i = s->terms - 1; (i >= 0) && (t < size); i--) {
if (s->decorr[i].value > 8) {
s->decorr[i].samplesA[0] = wp_exp2(AV_RL16(buf)); buf += 2;
s->decorr[i].samplesA[1] = wp_exp2(AV_RL16(buf)); buf += 2;
if (s->stereo_in) {
s->decorr[i].samplesB[0] = wp_exp2(AV_RL16(buf)); buf += 2;
s->decorr[i].samplesB[1] = wp_exp2(AV_RL16(buf)); buf += 2;
t += 4;
}
t += 4;
} else if (s->decorr[i].value < 0) {
s->decorr[i].samplesA[0] = wp_exp2(AV_RL16(buf)); buf += 2;
s->decorr[i].samplesB[0] = wp_exp2(AV_RL16(buf)); buf += 2;
t += 4;
} else {
for (j = 0; j < s->decorr[i].value; j++) {
s->decorr[i].samplesA[j] = wp_exp2(AV_RL16(buf)); buf += 2;
if (s->stereo_in) {
s->decorr[i].samplesB[j] = wp_exp2(AV_RL16(buf)); buf += 2;
}
}
t += s->decorr[i].value * 2 * (s->stereo_in + 1);
}
}
got_samples = 1;
break;
case WP_ID_ENTROPY:
if (size != 6 * (s->stereo_in + 1)) {
av_log(avctx, AV_LOG_ERROR, "Entropy vars size should be %i, "
"got %i", 6 * (s->stereo_in + 1), size);
buf += ssize;
continue;
}
for (j = 0; j <= s->stereo_in; j++) {
for (i = 0; i < 3; i++) {
s->ch[j].median[i] = wp_exp2(AV_RL16(buf));
buf += 2;
}
}
got_entropy = 1;
break;
case WP_ID_HYBRID:
if (s->hybrid_bitrate) {
for (i = 0; i <= s->stereo_in; i++) {
s->ch[i].slow_level = wp_exp2(AV_RL16(buf));
buf += 2;
size -= 2;
}
}
for (i = 0; i < (s->stereo_in + 1); i++) {
s->ch[i].bitrate_acc = AV_RL16(buf) << 16;
buf += 2;
size -= 2;
}
if (size > 0) {
for (i = 0; i < (s->stereo_in + 1); i++) {
s->ch[i].bitrate_delta = wp_exp2((int16_t)AV_RL16(buf));
buf += 2;
}
} else {
for (i = 0; i < (s->stereo_in + 1); i++)
s->ch[i].bitrate_delta = 0;
}
got_hybrid = 1;
break;
case WP_ID_INT32INFO:
if (size != 4) {
av_log(avctx, AV_LOG_ERROR, "Invalid INT32INFO, size = %i, sent_bits = %i\n", size, *buf);
buf += ssize;
continue;
}
if (buf[0])
s->extra_bits = buf[0];
else if (buf[1])
s->shift = buf[1];
else if (buf[2]){
s->and = s->or = 1;
s->shift = buf[2];
} else if(buf[3]) {
s->and = 1;
s->shift = buf[3];
}
/* original WavPack decoder forces 32-bit lossy sound to be treated
* as 24-bit one in order to have proper clipping
*/
if (s->hybrid && bpp == 4 && s->post_shift < 8 && s->shift > 8) {
s->post_shift += 8;
s->shift -= 8;
s->hybrid_maxclip >>= 8;
s->hybrid_minclip >>= 8;
}
buf += 4;
break;
case WP_ID_FLOATINFO:
if (size != 4) {
av_log(avctx, AV_LOG_ERROR, "Invalid FLOATINFO, size = %i\n", size);
buf += ssize;
continue;
}
s->float_flag = buf[0];
s->float_shift = buf[1];
s->float_max_exp = buf[2];
buf += 4;
got_float = 1;
break;
case WP_ID_DATA:
s->sc.offset = buf - orig_buf;
s->sc.size = size * 8;
init_get_bits(&s->gb, buf, size * 8);
s->data_size = size * 8;
buf += size;
got_bs = 1;
break;
case WP_ID_EXTRABITS:
if (size <= 4) {
av_log(avctx, AV_LOG_ERROR, "Invalid EXTRABITS, size = %i\n",
size);
buf += size;
continue;
}
s->extra_sc.offset = buf - orig_buf;
s->extra_sc.size = size * 8;
init_get_bits(&s->gb_extra_bits, buf, size * 8);
s->crc_extra_bits = get_bits_long(&s->gb_extra_bits, 32);
buf += size;
s->got_extra_bits = 1;
break;
case WP_ID_CHANINFO:
if (size <= 1) {
av_log(avctx, AV_LOG_ERROR, "Insufficient channel information\n");
return -1;
}
chan = *buf++;
switch (size - 2) {
case 0: chmask = *buf; break;
case 1: chmask = AV_RL16(buf); break;
case 2: chmask = AV_RL24(buf); break;
case 3: chmask = AV_RL32(buf); break;
case 5:
chan |= (buf[1] & 0xF) << 8;
chmask = AV_RL24(buf + 2);
break;
default:
av_log(avctx, AV_LOG_ERROR, "Invalid channel info size %d\n",
size);
chan = avctx->channels;
chmask = avctx->channel_layout;
}
if (chan != avctx->channels) {
av_log(avctx, AV_LOG_ERROR, "Block reports total %d channels, "
"decoder believes it's %d channels\n", chan,
avctx->channels);
return -1;
}
if (!avctx->channel_layout)
avctx->channel_layout = chmask;
buf += size - 1;
break;
default:
buf += size;
}
if (id & WP_IDF_ODD)
buf++;
}
if (!got_terms) {
av_log(avctx, AV_LOG_ERROR, "No block with decorrelation terms\n");
return -1;
}
if (!got_weights) {
av_log(avctx, AV_LOG_ERROR, "No block with decorrelation weights\n");
return -1;
}
if (!got_samples) {
av_log(avctx, AV_LOG_ERROR, "No block with decorrelation samples\n");
return -1;
}
if (!got_entropy) {
av_log(avctx, AV_LOG_ERROR, "No block with entropy info\n");
return -1;
}
if (s->hybrid && !got_hybrid) {
av_log(avctx, AV_LOG_ERROR, "Hybrid config not found\n");
return -1;
}
if (!got_bs) {
av_log(avctx, AV_LOG_ERROR, "Packed samples not found\n");
return -1;
}
if (!got_float && avctx->sample_fmt == AV_SAMPLE_FMT_FLT) {
av_log(avctx, AV_LOG_ERROR, "Float information not found\n");
return -1;
}
if (s->got_extra_bits && avctx->sample_fmt != AV_SAMPLE_FMT_FLT) {
const int size = get_bits_left(&s->gb_extra_bits);
const int wanted = s->samples * s->extra_bits << s->stereo_in;
if (size < wanted) {
av_log(avctx, AV_LOG_ERROR, "Too small EXTRABITS\n");
s->got_extra_bits = 0;
}
}
if (s->stereo_in) {
if (avctx->sample_fmt == AV_SAMPLE_FMT_S16)
samplecount = wv_unpack_stereo(s, &s->gb, samples, AV_SAMPLE_FMT_S16);
else if (avctx->sample_fmt == AV_SAMPLE_FMT_S32)
samplecount = wv_unpack_stereo(s, &s->gb, samples, AV_SAMPLE_FMT_S32);
else
samplecount = wv_unpack_stereo(s, &s->gb, samples, AV_SAMPLE_FMT_FLT);
if (samplecount < 0)
return -1;
samplecount >>= 1;
} else {
const int channel_stride = avctx->channels;
if (avctx->sample_fmt == AV_SAMPLE_FMT_S16)
samplecount = wv_unpack_mono(s, &s->gb, samples, AV_SAMPLE_FMT_S16);
else if (avctx->sample_fmt == AV_SAMPLE_FMT_S32)
samplecount = wv_unpack_mono(s, &s->gb, samples, AV_SAMPLE_FMT_S32);
else
samplecount = wv_unpack_mono(s, &s->gb, samples, AV_SAMPLE_FMT_FLT);
if (samplecount < 0)
return -1;
if (s->stereo && avctx->sample_fmt == AV_SAMPLE_FMT_S16) {
int16_t *dst = (int16_t*)samples + 1;
int16_t *src = (int16_t*)samples;
int cnt = samplecount;
while (cnt--) {
*dst = *src;
src += channel_stride;
dst += channel_stride;
}
} else if (s->stereo && avctx->sample_fmt == AV_SAMPLE_FMT_S32) {
int32_t *dst = (int32_t*)samples + 1;
int32_t *src = (int32_t*)samples;
int cnt = samplecount;
while (cnt--) {
*dst = *src;
src += channel_stride;
dst += channel_stride;
}
} else if (s->stereo) {
float *dst = (float*)samples + 1;
float *src = (float*)samples;
int cnt = samplecount;
while (cnt--) {
*dst = *src;
src += channel_stride;
dst += channel_stride;
}
}
}
*got_frame_ptr = 1;
return samplecount * bpp;
}
static void wavpack_decode_flush(AVCodecContext *avctx)
{
WavpackContext *s = avctx->priv_data;
int i;
for (i = 0; i < s->fdec_num; i++)
wv_reset_saved_context(s->fdec[i]);
}
static int wavpack_decode_frame(AVCodecContext *avctx, void *data,
int *got_frame_ptr, AVPacket *avpkt)
{
WavpackContext *s = avctx->priv_data;
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
int frame_size, ret, frame_flags;
int samplecount = 0;
s->block = 0;
s->ch_offset = 0;
/* determine number of samples */
if (s->mkv_mode) {
s->samples = AV_RL32(buf); buf += 4;
frame_flags = AV_RL32(buf);
} else {
if (s->multichannel) {
s->samples = AV_RL32(buf + 4);
frame_flags = AV_RL32(buf + 8);
} else {
s->samples = AV_RL32(buf);
frame_flags = AV_RL32(buf + 4);
}
}
if (s->samples <= 0 || s->samples > WV_MAX_SAMPLES) {
av_log(avctx, AV_LOG_ERROR, "Invalid number of samples: %d\n",
s->samples);
return AVERROR(EINVAL);
}
if (frame_flags & 0x80) {
avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
} else if ((frame_flags & 0x03) <= 1) {
avctx->sample_fmt = AV_SAMPLE_FMT_S16;
} else {
avctx->sample_fmt = AV_SAMPLE_FMT_S32;
avctx->bits_per_raw_sample = ((frame_flags & 0x03) + 1) << 3;
}
/* get output buffer */
s->frame.nb_samples = s->samples + 1;
if ((ret = ff_get_buffer(avctx, &s->frame)) < 0) {
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return ret;
}
s->frame.nb_samples = s->samples;
while (buf_size > 0) {
if (!s->multichannel) {
frame_size = buf_size;
} else {
if (!s->mkv_mode) {
frame_size = AV_RL32(buf) - 12; buf += 4; buf_size -= 4;
} else {
if (buf_size < 12) //MKV files can have zero flags after last block
break;
frame_size = AV_RL32(buf + 8) + 12;
}
}
if (frame_size < 0 || frame_size > buf_size) {
av_log(avctx, AV_LOG_ERROR, "Block %d has invalid size (size %d "
"vs. %d bytes left)\n", s->block, frame_size, buf_size);
wavpack_decode_flush(avctx);
return AVERROR_INVALIDDATA;
}
if ((samplecount = wavpack_decode_block(avctx, s->block,
s->frame.data[0], got_frame_ptr,
buf, frame_size)) < 0) {
wavpack_decode_flush(avctx);
return AVERROR_INVALIDDATA;
}
s->block++;
buf += frame_size; buf_size -= frame_size;
}
if (*got_frame_ptr)
*(AVFrame *)data = s->frame;
return avpkt->size;
}
AVCodec ff_wavpack_decoder = {
.name = "wavpack",
.type = AVMEDIA_TYPE_AUDIO,
.id = AV_CODEC_ID_WAVPACK,
.priv_data_size = sizeof(WavpackContext),
.init = wavpack_decode_init,
.close = wavpack_decode_end,
.decode = wavpack_decode_frame,
.flush = wavpack_decode_flush,
.capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("WavPack"),
};
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