ffmpeg / libavcodec / wavpack.c @ ad1ea1f1
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/*


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* WavPack lossless audio decoder

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* Copyright (c) 2006 Konstantin Shishkov

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*

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* This file is part of FFmpeg.

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*

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* FFmpeg is free software; you can redistribute it and/or

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* modify it under the terms of the GNU Lesser General Public

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* License as published by the Free Software Foundation; either

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* version 2.1 of the License, or (at your option) any later version.

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*

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* FFmpeg is distributed in the hope that it will be useful,

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* but WITHOUT ANY WARRANTY; without even the implied warranty of

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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

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* Lesser General Public License for more details.

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*

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* You should have received a copy of the GNU Lesser General Public

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* License along with FFmpeg; if not, write to the Free Software

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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 021101301 USA

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*/

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#define ALT_BITSTREAM_READER_LE

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#include "avcodec.h" 
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#include "bitstream.h" 
24  
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/**

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* @file wavpack.c

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* WavPack lossless audio decoder

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*/

29  
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#define WV_JOINT 0x0010 
31  
32 
enum WP_ID_Flags{

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WP_IDF_MASK = 0x1F,

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WP_IDF_IGNORE = 0x20,

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WP_IDF_ODD = 0x40,

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WP_IDF_LONG = 0x80

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}; 
38  
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enum WP_ID{

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WP_ID_DUMMY = 0,

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WP_ID_ENCINFO, 
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WP_ID_DECTERMS, 
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WP_ID_DECWEIGHTS, 
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WP_ID_DECSAMPLES, 
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WP_ID_ENTROPY, 
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WP_ID_HYBRID, 
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WP_ID_SHAPING, 
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WP_ID_FLOATINFO, 
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WP_ID_INT32INFO, 
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WP_ID_DATA, 
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WP_ID_CORR, 
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WP_ID_FLT, 
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WP_ID_CHANINFO 
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}; 
55  
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#define MAX_TERMS 16 
57  
58 
typedef struct Decorr { 
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int delta;

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int value;

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int weightA;

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int weightB;

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int samplesA[8]; 
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int samplesB[8]; 
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} Decorr; 
66  
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typedef struct WavpackContext { 
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AVCodecContext *avctx; 
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int stereo;

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int joint;

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uint32_t CRC; 
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GetBitContext gb; 
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int data_size; // in bits 
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int samples;

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int median[6]; 
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int terms;

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Decorr decorr[MAX_TERMS]; 
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int zero, one, zeroes;

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} WavpackContext; 
80  
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// exponent table copied from WavPack source

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static const uint8_t wp_exp2_table [256] = { 
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0x00, 0x01, 0x01, 0x02, 0x03, 0x03, 0x04, 0x05, 0x06, 0x06, 0x07, 0x08, 0x08, 0x09, 0x0a, 0x0b, 
84 
0x0b, 0x0c, 0x0d, 0x0e, 0x0e, 0x0f, 0x10, 0x10, 0x11, 0x12, 0x13, 0x13, 0x14, 0x15, 0x16, 0x16, 
85 
0x17, 0x18, 0x19, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1d, 0x1e, 0x1f, 0x20, 0x20, 0x21, 0x22, 0x23, 
86 
0x24, 0x24, 0x25, 0x26, 0x27, 0x28, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2c, 0x2d, 0x2e, 0x2f, 0x30, 
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0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3a, 0x3b, 0x3c, 0x3d, 
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0x3e, 0x3f, 0x40, 0x41, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x48, 0x49, 0x4a, 0x4b, 
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0x4c, 0x4d, 0x4e, 0x4f, 0x50, 0x51, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 
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0x5b, 0x5c, 0x5d, 0x5e, 0x5e, 0x5f, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 
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0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 
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0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x87, 0x88, 0x89, 0x8a, 
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0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0x90, 0x91, 0x92, 0x93, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0x9b, 
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0x9c, 0x9d, 0x9f, 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 
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0xaf, 0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xbc, 0xbd, 0xbe, 0xbf, 0xc0, 
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0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc8, 0xc9, 0xca, 0xcb, 0xcd, 0xce, 0xcf, 0xd0, 0xd2, 0xd3, 0xd4, 
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0xd6, 0xd7, 0xd8, 0xd9, 0xdb, 0xdc, 0xdd, 0xde, 0xe0, 0xe1, 0xe2, 0xe4, 0xe5, 0xe6, 0xe8, 0xe9, 
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0xea, 0xec, 0xed, 0xee, 0xf0, 0xf1, 0xf2, 0xf4, 0xf5, 0xf6, 0xf8, 0xf9, 0xfa, 0xfc, 0xfd, 0xff 
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}; 
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static av_always_inline int wp_exp2(int16_t val) 
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{ 
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int res, neg = 0; 
104  
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if(val < 0){ 
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val = val; 
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neg = 1;

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} 
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res = wp_exp2_table[val & 0xFF]  0x100; 
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val >>= 8;

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res = (val > 9) ? (res << (val  9)) : (res >> (9  val)); 
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return neg ? res : res;

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} 
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static inline int get_unary(GetBitContext *gb){ 
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int r=0; 
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while(get_bits1(gb) && r<33)r++; 
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return r;

120 
} 
121  
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// macros for manipulating median values

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#define GET_MED(n) ((median[n] >> 4) + 1) 
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#define DEC_MED(n) median[n] = ((median[n] + (128>>n)  2) / (128>>n)) * 2 
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#define INC_MED(n) median[n] += ((median[n] + (128>>n)) / (128>>n)) * 5 
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// macros for applying weight

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#define UPDATE_WEIGHT_CLIP(weight, delta, samples, in) \

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if(samples && in){ \

130 
if((samples ^ in) < 0){ \ 
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weight = delta; \ 
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if(weight < 1024) weight = 1024; \ 
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}else{ \

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weight += delta; \ 
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if(weight > 1024) weight = 1024; \ 
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} \ 
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} 
138  
139  
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static av_always_inline int get_tail(GetBitContext *gb, int k) 
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{ 
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int p, e, res;

143  
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if(k<1)return 0; 
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p = av_log2(k); 
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e = (1 << (p + 1))  k  1; 
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res = p ? get_bits(gb, p) : 0;

148 
if(res >= e){

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res = (res<<1)  e + get_bits1(gb);

150 
} 
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return res;

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} 
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static int wv_get_value(WavpackContext *ctx, GetBitContext *gb, int *median, int *last) 
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{ 
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int t, t2;

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int sign, base, add, ret;

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*last = 0;

160  
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if((ctx>median[0] < 2U) && (ctx>median[3] < 2U) && !ctx>zero && !ctx>one){ 
162 
if(ctx>zeroes){

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ctx>zeroes; 
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if(ctx>zeroes)

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return 0; 
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}else{

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t = get_unary(gb); 
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if(t >= 2) t = get_bits(gb, t  1)  (1 << (t1)); 
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ctx>zeroes = t; 
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if(ctx>zeroes){

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memset(ctx>median, 0, sizeof(ctx>median)); 
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return 0; 
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} 
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} 
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} 
176  
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if(get_bits_count(gb) >= ctx>data_size){

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*last = 1;

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return 0; 
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} 
181  
182 
if(ctx>zero){

183 
t = 0;

184 
ctx>zero = 0;

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}else{

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t = get_unary(gb); 
187 
if(get_bits_count(gb) >= ctx>data_size){

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*last = 1;

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return 0; 
190 
} 
191 
if(t == 16) { 
192 
t2 = get_unary(gb); 
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if(t2 < 2) t += t2; 
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else t += get_bits(gb, t2  1)  (1 << (t2  1)); 
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} 
196  
197 
if(ctx>one){

198 
ctx>one = t&1;

199 
t = (t>>1) + 1; 
200 
}else{

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ctx>one = t&1;

202 
t >>= 1;

203 
} 
204 
ctx>zero = !ctx>one; 
205 
} 
206  
207 
if(!t){

208 
base = 0;

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add = GET_MED(0)  1; 
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DEC_MED(0);

211 
}else if(t == 1){ 
212 
base = GET_MED(0);

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add = GET_MED(1)  1; 
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INC_MED(0);

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DEC_MED(1);

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}else if(t == 2){ 
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base = GET_MED(0) + GET_MED(1); 
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add = GET_MED(2)  1; 
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INC_MED(0);

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INC_MED(1);

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DEC_MED(2);

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}else{

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base = GET_MED(0) + GET_MED(1) + GET_MED(2) * (t  2); 
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add = GET_MED(2)  1; 
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INC_MED(0);

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INC_MED(1);

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INC_MED(2);

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} 
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ret = base + get_tail(gb, add); 
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sign = get_bits1(gb); 
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return sign ? ~ret : ret;

232 
} 
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234 
static int wv_unpack_stereo(WavpackContext *s, GetBitContext *gb, int16_t *dst) 
235 
{ 
236 
int i, j, count = 0; 
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int last, t;

238 
int A, B, L, L2, R, R2;

239 
int pos = 0; 
240 
uint32_t crc = 0xFFFFFFFF;

241  
242 
s>one = s>zero = s>zeroes = 0;

243 
do{

244 
L = wv_get_value(s, gb, s>median, &last); 
245 
if(last) break; 
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R = wv_get_value(s, gb, s>median + 3, &last);

247 
if(last) break; 
248 
for(i = 0; i < s>terms; i++){ 
249 
t = s>decorr[i].value; 
250 
j = 0;

251 
if(t > 0){ 
252 
if(t > 8){ 
253 
if(t & 1){ 
254 
A = 2 * s>decorr[i].samplesA[0]  s>decorr[i].samplesA[1]; 
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B = 2 * s>decorr[i].samplesB[0]  s>decorr[i].samplesB[1]; 
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}else{

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A = (3 * s>decorr[i].samplesA[0]  s>decorr[i].samplesA[1]) >> 1; 
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B = (3 * s>decorr[i].samplesB[0]  s>decorr[i].samplesB[1]) >> 1; 
259 
} 
260 
s>decorr[i].samplesA[1] = s>decorr[i].samplesA[0]; 
261 
s>decorr[i].samplesB[1] = s>decorr[i].samplesB[0]; 
262 
j = 0;

263 
}else{

264 
A = s>decorr[i].samplesA[pos]; 
265 
B = s>decorr[i].samplesB[pos]; 
266 
j = (pos + t) & 7;

267 
} 
268 
L2 = L + ((s>decorr[i].weightA * A + 512) >> 10); 
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R2 = R + ((s>decorr[i].weightB * B + 512) >> 10); 
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if(A && L) s>decorr[i].weightA = ((((L ^ A) >> 30) & 2)  1) * s>decorr[i].delta; 
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if(B && R) s>decorr[i].weightB = ((((R ^ B) >> 30) & 2)  1) * s>decorr[i].delta; 
272 
s>decorr[i].samplesA[j] = L = L2; 
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s>decorr[i].samplesB[j] = R = R2; 
274 
}else if(t == 1){ 
275 
L2 = L + ((s>decorr[i].weightA * s>decorr[i].samplesA[0] + 512) >> 10); 
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UPDATE_WEIGHT_CLIP(s>decorr[i].weightA, s>decorr[i].delta, s>decorr[i].samplesA[0], L);

277 
L = L2; 
278 
R2 = R + ((s>decorr[i].weightB * L2 + 512) >> 10); 
279 
UPDATE_WEIGHT_CLIP(s>decorr[i].weightB, s>decorr[i].delta, L2, R); 
280 
R = R2; 
281 
s>decorr[i].samplesA[0] = R;

282 
}else{

283 
R2 = R + ((s>decorr[i].weightB * s>decorr[i].samplesB[0] + 512) >> 10); 
284 
UPDATE_WEIGHT_CLIP(s>decorr[i].weightB, s>decorr[i].delta, s>decorr[i].samplesB[0], R);

285 
R = R2; 
286  
287 
if(t == 3){ 
288 
R2 = s>decorr[i].samplesA[0];

289 
s>decorr[i].samplesA[0] = R;

290 
} 
291  
292 
L2 = L + ((s>decorr[i].weightA * R2 + 512) >> 10); 
293 
UPDATE_WEIGHT_CLIP(s>decorr[i].weightA, s>decorr[i].delta, R2, L); 
294 
L = L2; 
295 
s>decorr[i].samplesB[0] = L;

296 
} 
297 
} 
298 
pos = (pos + 1) & 7; 
299 
if(s>joint)

300 
L += (R = (L >> 1));

301 
crc = (crc * 3 + L) * 3 + R; 
302 
*dst++ = L; 
303 
*dst++ = R; 
304  
305 
count++; 
306 
}while(!last && count < s>samples);

307  
308 
if(crc != s>CRC){

309 
av_log(s>avctx, AV_LOG_ERROR, "CRC error\n");

310 
return 1; 
311 
} 
312 
return count * 2; 
313 
} 
314  
315 
static int wv_unpack_mono(WavpackContext *s, GetBitContext *gb, int16_t *dst) 
316 
{ 
317 
int i, j, count = 0; 
318 
int last, t;

319 
int A, S, T;

320 
int pos = 0; 
321 
uint32_t crc = 0xFFFFFFFF;

322  
323 
s>one = s>zero = s>zeroes = 0;

324 
do{

325 
T = wv_get_value(s, gb, s>median, &last); 
326 
S = 0;

327 
if(last) break; 
328 
for(i = 0; i < s>terms; i++){ 
329 
t = s>decorr[i].value; 
330 
if(t > 8){ 
331 
if(t & 1) 
332 
A = 2 * s>decorr[i].samplesA[0]  s>decorr[i].samplesA[1]; 
333 
else

334 
A = (3 * s>decorr[i].samplesA[0]  s>decorr[i].samplesA[1]) >> 1; 
335 
s>decorr[i].samplesA[1] = s>decorr[i].samplesA[0]; 
336 
j = 0;

337 
}else{

338 
A = s>decorr[i].samplesA[pos]; 
339 
j = (pos + t) & 7;

340 
} 
341 
S = T + ((s>decorr[i].weightA * A + 512) >> 10); 
342 
if(A && T) s>decorr[i].weightA = ((((T ^ A) >> 30) & 2)  1) * s>decorr[i].delta; 
343 
s>decorr[i].samplesA[j] = T = S; 
344 
} 
345 
pos = (pos + 1) & 7; 
346 
crc = crc * 3 + S;

347 
*dst++ = S; 
348 
count++; 
349 
}while(!last && count < s>samples);

350  
351 
if(crc != s>CRC){

352 
av_log(s>avctx, AV_LOG_ERROR, "CRC error\n");

353 
return 1; 
354 
} 
355 
return count;

356 
} 
357  
358 
static int wavpack_decode_init(AVCodecContext *avctx) 
359 
{ 
360 
WavpackContext *s = avctx>priv_data; 
361  
362 
s>avctx = avctx; 
363 
s>stereo = (avctx>channels == 2);

364  
365 
return 0; 
366 
} 
367  
368 
static int wavpack_decode_close(AVCodecContext *avctx) 
369 
{ 
370 
// WavpackContext *s = avctx>priv_data;

371  
372 
return 0; 
373 
} 
374  
375 
static int wavpack_decode_frame(AVCodecContext *avctx, 
376 
void *data, int *data_size, 
377 
uint8_t *buf, int buf_size)

378 
{ 
379 
WavpackContext *s = avctx>priv_data; 
380 
int16_t *samples = data; 
381 
int samplecount;

382 
int got_terms = 0, got_weights = 0, got_samples = 0, got_entropy = 0, got_bs = 0; 
383 
uint8_t* buf_end = buf + buf_size; 
384 
int i, j, id, size, ssize, weights, t;

385  
386 
if (buf_size == 0){ 
387 
*data_size = 0;

388 
return 0; 
389 
} 
390  
391 
memset(s>decorr, 0, MAX_TERMS * sizeof(Decorr)); 
392  
393 
s>samples = AV_RL32(buf); buf += 4;

394 
if(!s>samples){

395 
*data_size = 0;

396 
return buf_size;

397 
} 
398 
/* should not happen but who knows */

399 
if(s>samples * 2 * avctx>channels > *data_size){ 
400 
av_log(avctx, AV_LOG_ERROR, "Packet size is too big to be handled in lavc!\n");

401 
return 1; 
402 
} 
403 
s>joint = AV_RL32(buf) & WV_JOINT; buf += 4;

404 
s>CRC = AV_RL32(buf); buf += 4;

405 
// parse metadata blocks

406 
while(buf < buf_end){

407 
id = *buf++; 
408 
size = *buf++; 
409 
if(id & WP_IDF_LONG) {

410 
size = (*buf++) << 8;

411 
size = (*buf++) << 16;

412 
} 
413 
size <<= 1; // size is specified in words 
414 
ssize = size; 
415 
if(id & WP_IDF_ODD) size;

416 
if(size < 0){ 
417 
av_log(avctx, AV_LOG_ERROR, "Got incorrect block %02X with size %i\n", id, size);

418 
break;

419 
} 
420 
if(buf + ssize > buf_end){

421 
av_log(avctx, AV_LOG_ERROR, "Block size %i is out of bounds\n", size);

422 
break;

423 
} 
424 
if(id & WP_IDF_IGNORE){

425 
buf += ssize; 
426 
continue;

427 
} 
428 
switch(id & WP_IDF_MASK){

429 
case WP_ID_DECTERMS:

430 
s>terms = size; 
431 
if(s>terms > MAX_TERMS){

432 
av_log(avctx, AV_LOG_ERROR, "Too many decorrelation terms\n");

433 
buf += ssize; 
434 
continue;

435 
} 
436 
for(i = 0; i < s>terms; i++) { 
437 
s>decorr[s>terms  i  1].value = (*buf & 0x1F)  5; 
438 
s>decorr[s>terms  i  1].delta = *buf >> 5; 
439 
buf++; 
440 
} 
441 
got_terms = 1;

442 
break;

443 
case WP_ID_DECWEIGHTS:

444 
if(!got_terms){

445 
av_log(avctx, AV_LOG_ERROR, "No decorrelation terms met\n");

446 
continue;

447 
} 
448 
weights = size >> s>stereo; 
449 
if(weights > MAX_TERMS  weights > s>terms){

450 
av_log(avctx, AV_LOG_ERROR, "Too many decorrelation weights\n");

451 
buf += ssize; 
452 
continue;

453 
} 
454 
for(i = 0; i < weights; i++) { 
455 
t = (int8_t)(*buf++); 
456 
s>decorr[s>terms  i  1].weightA = t << 3; 
457 
if(s>decorr[s>terms  i  1].weightA > 0) 
458 
s>decorr[s>terms  i  1].weightA += (s>decorr[s>terms  i  1].weightA + 64) >> 7; 
459 
if(s>stereo){

460 
t = (int8_t)(*buf++); 
461 
s>decorr[s>terms  i  1].weightB = t << 3; 
462 
if(s>decorr[s>terms  i  1].weightB > 0) 
463 
s>decorr[s>terms  i  1].weightB += (s>decorr[s>terms  i  1].weightB + 64) >> 7; 
464 
} 
465 
} 
466 
got_weights = 1;

467 
break;

468 
case WP_ID_DECSAMPLES:

469 
if(!got_terms){

470 
av_log(avctx, AV_LOG_ERROR, "No decorrelation terms met\n");

471 
continue;

472 
} 
473 
t = 0;

474 
for(i = s>terms  1; (i >= 0) && (t < size); i) { 
475 
if(s>decorr[i].value > 8){ 
476 
s>decorr[i].samplesA[0] = wp_exp2(AV_RL16(buf)); buf += 2; 
477 
s>decorr[i].samplesA[1] = wp_exp2(AV_RL16(buf)); buf += 2; 
478 
if(s>stereo){

479 
s>decorr[i].samplesB[0] = wp_exp2(AV_RL16(buf)); buf += 2; 
480 
s>decorr[i].samplesB[1] = wp_exp2(AV_RL16(buf)); buf += 2; 
481 
t += 4;

482 
} 
483 
t += 4;

484 
}else if(s>decorr[i].value < 0){ 
485 
s>decorr[i].samplesA[0] = wp_exp2(AV_RL16(buf)); buf += 2; 
486 
s>decorr[i].samplesB[0] = wp_exp2(AV_RL16(buf)); buf += 2; 
487 
t += 4;

488 
}else{

489 
for(j = 0; j < s>decorr[i].value; j++){ 
490 
s>decorr[i].samplesA[j] = wp_exp2(AV_RL16(buf)); buf += 2;

491 
if(s>stereo){

492 
s>decorr[i].samplesB[j] = wp_exp2(AV_RL16(buf)); buf += 2;

493 
} 
494 
} 
495 
t += s>decorr[i].value * 2 * avctx>channels;

496 
} 
497 
} 
498 
got_samples = 1;

499 
break;

500 
case WP_ID_ENTROPY:

501 
if(size != 6 * avctx>channels){ 
502 
av_log(avctx, AV_LOG_ERROR, "Entropy vars size should be %i, got %i", 6 * avctx>channels, size); 
503 
buf += ssize; 
504 
continue;

505 
} 
506 
for(i = 0; i < 3 * avctx>channels; i++){ 
507 
s>median[i] = wp_exp2(AV_RL16(buf)); 
508 
buf += 2;

509 
} 
510 
got_entropy = 1;

511 
break;

512 
case WP_ID_DATA:

513 
init_get_bits(&s>gb, buf, size * 8);

514 
s>data_size = size * 8;

515 
buf += size; 
516 
got_bs = 1;

517 
break;

518 
default:

519 
buf += size; 
520 
} 
521 
if(id & WP_IDF_ODD) buf++;

522 
} 
523 
if(!got_terms){

524 
av_log(avctx, AV_LOG_ERROR, "No block with decorrelation terms\n");

525 
return 1; 
526 
} 
527 
if(!got_weights){

528 
av_log(avctx, AV_LOG_ERROR, "No block with decorrelation weights\n");

529 
return 1; 
530 
} 
531 
if(!got_samples){

532 
av_log(avctx, AV_LOG_ERROR, "No block with decorrelation samples\n");

533 
return 1; 
534 
} 
535 
if(!got_entropy){

536 
av_log(avctx, AV_LOG_ERROR, "No block with entropy info\n");

537 
return 1; 
538 
} 
539 
if(!got_bs){

540 
av_log(avctx, AV_LOG_ERROR, "Packed samples not found\n");

541 
return 1; 
542 
} 
543  
544 
if(s>stereo)

545 
samplecount = wv_unpack_stereo(s, &s>gb, samples); 
546 
else

547 
samplecount = wv_unpack_mono(s, &s>gb, samples); 
548 
*data_size = samplecount * 2;

549  
550 
return buf_size;

551 
} 
552  
553 
AVCodec wavpack_decoder = { 
554 
"wavpack",

555 
CODEC_TYPE_AUDIO, 
556 
CODEC_ID_WAVPACK, 
557 
sizeof(WavpackContext),

558 
wavpack_decode_init, 
559 
NULL,

560 
wavpack_decode_close, 
561 
wavpack_decode_frame, 
562 
}; 