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			803 lines
		
	
	
		
			24 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			803 lines
		
	
	
		
			24 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * DV decoder
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|  * Copyright (c) 2002 Fabrice Bellard.
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|  *
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|  * This library 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 of the License, or (at your option) any later version.
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|  *
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|  * This library 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 this library; if not, write to the Free Software
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|  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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|  */
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| 
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| /**
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|  * @file dv.c
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|  * DV decoder.
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|  */
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| #include "avcodec.h"
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| #include "dsputil.h"
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| #include "mpegvideo.h"
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| #include "simple_idct.h"
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| 
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| #define NTSC_FRAME_SIZE 120000
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| #define PAL_FRAME_SIZE  144000
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| 
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| #define TEX_VLC_BITS 9
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| 
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| typedef struct DVVideoDecodeContext {
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|     AVCodecContext *avctx;
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|     GetBitContext gb;
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|     VLC *vlc;
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|     int sampling_411; /* 0 = 420, 1 = 411 */
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|     int width, height;
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|     uint8_t *current_picture[3]; /* picture structure */
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|     AVFrame picture;
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|     int linesize[3];
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|     DCTELEM block[5*6][64] __align8;
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|     uint8_t dv_zigzag[2][64];
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|     uint8_t idct_permutation[64];
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|     /* XXX: move it to static storage ? */
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|     uint8_t dv_shift[2][22][64];
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|     void (*idct_put[2])(uint8_t *dest, int line_size, DCTELEM *block);
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| } DVVideoDecodeContext;
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| 
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| #include "dvdata.h"
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| 
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| static VLC dv_vlc;
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| /* XXX: also include quantization */
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| static RL_VLC_ELEM *dv_rl_vlc[1];
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| 
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| static void dv_build_unquantize_tables(DVVideoDecodeContext *s)
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| {
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|     int i, q, j;
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| 
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|     /* NOTE: max left shift is 6 */
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|     for(q = 0; q < 22; q++) {
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|         /* 88 unquant */
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|         for(i = 1; i < 64; i++) {
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|             /* 88 table */
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|             j = s->idct_permutation[i];
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|             s->dv_shift[0][q][j] =
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|                 dv_quant_shifts[q][dv_88_areas[i]] + 1;
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|         }
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|         
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|         /* 248 unquant */
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|         for(i = 1; i < 64; i++) {
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|             /* 248 table */
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|             s->dv_shift[1][q][i] =  
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|                     dv_quant_shifts[q][dv_248_areas[i]] + 1;
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|         }
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|     }
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| }
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| 
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| static int dvvideo_decode_init(AVCodecContext *avctx)
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| {
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|     DVVideoDecodeContext *s = avctx->priv_data;
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|     MpegEncContext s2;
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|     static int done=0;
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| 
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|     if (!done) {
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|         int i;
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| 
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|         done = 1;
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| 
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|         /* NOTE: as a trick, we use the fact the no codes are unused
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|            to accelerate the parsing of partial codes */
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|         init_vlc(&dv_vlc, TEX_VLC_BITS, NB_DV_VLC, 
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|                  dv_vlc_len, 1, 1, dv_vlc_bits, 2, 2);
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| 
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|         dv_rl_vlc[0] = av_malloc(dv_vlc.table_size * sizeof(RL_VLC_ELEM));
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|         for(i = 0; i < dv_vlc.table_size; i++){
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|             int code= dv_vlc.table[i][0];
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|             int len = dv_vlc.table[i][1];
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|             int level, run;
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|         
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|             if(len<0){ //more bits needed
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|                 run= 0;
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|                 level= code;
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|             } else if (code == (NB_DV_VLC - 1)) {
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|                 /* EOB */
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|                 run = 0;
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|                 level = 256;
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|             } else {
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|                 run=   dv_vlc_run[code] + 1;
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|                 level= dv_vlc_level[code];
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|             }
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|             dv_rl_vlc[0][i].len = len;
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|             dv_rl_vlc[0][i].level = level;
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|             dv_rl_vlc[0][i].run = run;
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|         }
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|     }
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| 
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|     /* ugly way to get the idct & scantable */
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|     /* XXX: fix it */
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|     memset(&s2, 0, sizeof(MpegEncContext));
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|     s2.avctx = avctx;
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|     dsputil_init(&s2.dsp, avctx);
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|     if (DCT_common_init(&s2) < 0)
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|        return -1;
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| 
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|     s->idct_put[0] = s2.dsp.idct_put;
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|     memcpy(s->idct_permutation, s2.dsp.idct_permutation, 64);
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|     memcpy(s->dv_zigzag[0], s2.intra_scantable.permutated, 64);
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| 
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|     /* XXX: use MMX also for idct248 */
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|     s->idct_put[1] = simple_idct248_put;
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|     memcpy(s->dv_zigzag[1], dv_248_zigzag, 64);
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| 
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|     /* XXX: do it only for constant case */
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|     dv_build_unquantize_tables(s);
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|     
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|     return 0;
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| }
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| 
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| //#define VLC_DEBUG
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| 
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| typedef struct BlockInfo {
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|     const uint8_t *shift_table;
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|     const uint8_t *scan_table;
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|     uint8_t pos; /* position in block */
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|     uint8_t eob_reached; /* true if EOB has been reached */
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|     uint8_t dct_mode;
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|     uint8_t partial_bit_count;
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|     uint16_t partial_bit_buffer;
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|     int shift_offset;
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| } BlockInfo;
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| 
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| /* block size in bits */
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| static const uint16_t block_sizes[6] = {
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|     112, 112, 112, 112, 80, 80
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| };
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| 
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| #ifndef ALT_BITSTREAM_READER
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| #warning only works with ALT_BITSTREAM_READER
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| #endif
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| 
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| /* decode ac coefs */
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| static void dv_decode_ac(DVVideoDecodeContext *s, 
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|                          BlockInfo *mb, DCTELEM *block, int last_index)
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| {
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|     int last_re_index;
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|     int shift_offset = mb->shift_offset;
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|     const uint8_t *scan_table = mb->scan_table;
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|     const uint8_t *shift_table = mb->shift_table;
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|     int pos = mb->pos;
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|     int level, pos1, sign, run;
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|     int partial_bit_count;
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| #ifndef ALT_BITSTREAM_READER //FIXME
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|     int re_index=0; 
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|     int re1_index=0;
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| #endif
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|     OPEN_READER(re, &s->gb);
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|     
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| #ifdef VLC_DEBUG
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|     printf("start\n");
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| #endif
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| 
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|     /* if we must parse a partial vlc, we do it here */
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|     partial_bit_count = mb->partial_bit_count;
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|     if (partial_bit_count > 0) {
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|         uint8_t buf[4];
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|         uint32_t v;
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|         int l, l1;
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|         GetBitContext gb1;
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| 
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|         /* build the dummy bit buffer */
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|         l = 16 - partial_bit_count;
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|         UPDATE_CACHE(re, &s->gb);
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| #ifdef VLC_DEBUG
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|         printf("show=%04x\n", SHOW_UBITS(re, &s->gb, 16));
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| #endif
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|         v = (mb->partial_bit_buffer << l) | SHOW_UBITS(re, &s->gb, l);
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|         buf[0] = v >> 8;
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|         buf[1] = v;
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| #ifdef VLC_DEBUG
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|         printf("v=%04x cnt=%d %04x\n", 
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|                v, partial_bit_count, (mb->partial_bit_buffer << l));
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| #endif
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|         /* try to read the codeword */
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|         init_get_bits(&gb1, buf, 4*8);
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|         {
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|             OPEN_READER(re1, &gb1);
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|             UPDATE_CACHE(re1, &gb1);
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|             GET_RL_VLC(level, run, re1, &gb1, dv_rl_vlc[0], 
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|                        TEX_VLC_BITS, 2);
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|             l = re1_index;
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|             CLOSE_READER(re1, &gb1);
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|         }
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| #ifdef VLC_DEBUG
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|         printf("****run=%d level=%d size=%d\n", run, level, l);
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| #endif
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|         /* compute codeword length */
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|         l1 = (level != 256 && level != 0);
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|         /* if too long, we cannot parse */
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|         l -= partial_bit_count;
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|         if ((re_index + l + l1) > last_index)
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|             return;
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|         /* skip read bits */
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|         last_re_index = 0; /* avoid warning */
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|         re_index += l;
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|         /* by definition, if we can read the vlc, all partial bits
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|            will be read (otherwise we could have read the vlc before) */
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|         mb->partial_bit_count = 0;
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|         UPDATE_CACHE(re, &s->gb);
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|         goto handle_vlc;
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|     }
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| 
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|     /* get the AC coefficients until last_index is reached */
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|     for(;;) {
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|         UPDATE_CACHE(re, &s->gb);
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| #ifdef VLC_DEBUG
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|         printf("%2d: bits=%04x index=%d\n", 
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|                pos, SHOW_UBITS(re, &s->gb, 16), re_index);
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| #endif
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|         last_re_index = re_index;
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|         GET_RL_VLC(level, run, re, &s->gb, dv_rl_vlc[0], 
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|                    TEX_VLC_BITS, 2);
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|     handle_vlc:
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| #ifdef VLC_DEBUG
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|         printf("run=%d level=%d\n", run, level);
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| #endif
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|         if (level == 256) {
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|             if (re_index > last_index) {
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|             cannot_read:
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|                 /* put position before read code */
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|                 re_index = last_re_index;
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|                 mb->eob_reached = 0;
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|                 break;
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|             }
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|             /* EOB */
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|             mb->eob_reached = 1;
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|             break;
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|         } else if (level != 0) {
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|             if ((re_index + 1) > last_index)
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|                 goto cannot_read;
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|             sign = SHOW_SBITS(re, &s->gb, 1);
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|             level = (level ^ sign) - sign;
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|             LAST_SKIP_BITS(re, &s->gb, 1);
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|             pos += run;
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|             /* error */
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|             if (pos >= 64) {
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|                 goto read_error;
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|             }
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|             pos1 = scan_table[pos];
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|             level = level << (shift_table[pos1] + shift_offset);
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|             block[pos1] = level;
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|             //            printf("run=%d level=%d shift=%d\n", run, level, shift_table[pos1]);
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|         } else {
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|             if (re_index > last_index)
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|                 goto cannot_read;
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|             /* level is zero: means run without coding. No
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|                sign is coded */
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|             pos += run;
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|             /* error */
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|             if (pos >= 64) {
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|             read_error:
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| #if defined(VLC_DEBUG) || 1
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|                 fprintf(stderr, "error pos=%d\n", pos);
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| #endif
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|                 /* for errors, we consider the eob is reached */
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|                 mb->eob_reached = 1;
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|                 break;
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|             }
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|         }
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|     }
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|     CLOSE_READER(re, &s->gb);
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|     mb->pos = pos;
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| }
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| 
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| static inline void bit_copy(PutBitContext *pb, GetBitContext *gb, int bits_left)
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| {
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|     while (bits_left >= 16) {
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|         put_bits(pb, 16, get_bits(gb, 16));
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|         bits_left -= 16;
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|     }
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|     if (bits_left > 0) {
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|         put_bits(pb, bits_left, get_bits(gb, bits_left));
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|     }
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| }
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| 
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| /* mb_x and mb_y are in units of 8 pixels */
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| static inline void dv_decode_video_segment(DVVideoDecodeContext *s, 
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|                                            uint8_t *buf_ptr1, 
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|                                            const uint16_t *mb_pos_ptr)
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| {
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|     int quant, dc, dct_mode, class1, j;
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|     int mb_index, mb_x, mb_y, v, last_index;
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|     DCTELEM *block, *block1;
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|     int c_offset, bits_left;
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|     uint8_t *y_ptr;
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|     BlockInfo mb_data[5 * 6], *mb, *mb1;
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|     void (*idct_put)(uint8_t *dest, int line_size, DCTELEM *block);
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|     uint8_t *buf_ptr;
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|     PutBitContext pb, vs_pb;
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|     uint8_t mb_bit_buffer[80 + 4]; /* allow some slack */
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|     int mb_bit_count;
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|     uint8_t vs_bit_buffer[5 * 80 + 4]; /* allow some slack */
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|     int vs_bit_count;
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|     
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|     memset(s->block, 0, sizeof(s->block));
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| 
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|     /* pass 1 : read DC and AC coefficients in blocks */
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|     buf_ptr = buf_ptr1;
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|     block1 = &s->block[0][0];
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|     mb1 = mb_data;
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|     init_put_bits(&vs_pb, vs_bit_buffer, 5 * 80, NULL, NULL);
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|     vs_bit_count = 0;
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|     for(mb_index = 0; mb_index < 5; mb_index++) {
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|         /* skip header */
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|         quant = buf_ptr[3] & 0x0f;
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|         buf_ptr += 4;
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|         init_put_bits(&pb, mb_bit_buffer, 80, NULL, NULL);
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|         mb_bit_count = 0;
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|         mb = mb1;
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|         block = block1;
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|         for(j = 0;j < 6; j++) {
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|             /* NOTE: size is not important here */
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|             init_get_bits(&s->gb, buf_ptr, 14*8);
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|             
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|             /* get the dc */
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|             dc = get_bits(&s->gb, 9);
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|             dc = (dc << (32 - 9)) >> (32 - 9);
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|             dct_mode = get_bits1(&s->gb);
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|             mb->dct_mode = dct_mode;
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|             mb->scan_table = s->dv_zigzag[dct_mode];
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|             class1 = get_bits(&s->gb, 2);
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|             mb->shift_offset = (class1 == 3);
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|             mb->shift_table = s->dv_shift[dct_mode]
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|                 [quant + dv_quant_offset[class1]];
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|             dc = dc << 2;
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|             /* convert to unsigned because 128 is not added in the
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|                standard IDCT */
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|             dc += 1024;
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|             block[0] = dc;
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|             last_index = block_sizes[j];
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|             buf_ptr += last_index >> 3;
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|             mb->pos = 0;
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|             mb->partial_bit_count = 0;
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| 
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|             dv_decode_ac(s, mb, block, last_index);
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| 
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|             /* write the remaining bits  in a new buffer only if the
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|                block is finished */
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|             bits_left = last_index - get_bits_count(&s->gb);
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|             if (mb->eob_reached) {
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|                 mb->partial_bit_count = 0;
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|                 mb_bit_count += bits_left;
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|                 bit_copy(&pb, &s->gb, bits_left);
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|             } else {
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|                 /* should be < 16 bits otherwise a codeword could have
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|                    been parsed */
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|                 mb->partial_bit_count = bits_left;
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|                 mb->partial_bit_buffer = get_bits(&s->gb, bits_left);
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|             }
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|             block += 64;
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|             mb++;
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|         }
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|         
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|         flush_put_bits(&pb);
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| 
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|         /* pass 2 : we can do it just after */
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| #ifdef VLC_DEBUG
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|         printf("***pass 2 size=%d\n", mb_bit_count);
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| #endif
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|         block = block1;
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|         mb = mb1;
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|         init_get_bits(&s->gb, mb_bit_buffer, 80*8);
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|         for(j = 0;j < 6; j++) {
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|             if (!mb->eob_reached && get_bits_count(&s->gb) < mb_bit_count) {
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|                 dv_decode_ac(s, mb, block, mb_bit_count);
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|                 /* if still not finished, no need to parse other blocks */
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|                 if (!mb->eob_reached) {
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|                     /* we could not parse the current AC coefficient,
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|                        so we add the remaining bytes */
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|                     bits_left = mb_bit_count - get_bits_count(&s->gb);
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|                     if (bits_left > 0) {
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|                         mb->partial_bit_count += bits_left;
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|                         mb->partial_bit_buffer = 
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|                             (mb->partial_bit_buffer << bits_left) | 
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|                             get_bits(&s->gb, bits_left);
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|                     }
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|                     goto next_mb;
 | |
|                 }
 | |
|             }
 | |
|             block += 64;
 | |
|             mb++;
 | |
|         }
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|         /* all blocks are finished, so the extra bytes can be used at
 | |
|            the video segment level */
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|         bits_left = mb_bit_count - get_bits_count(&s->gb);
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|         vs_bit_count += bits_left;
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|         bit_copy(&vs_pb, &s->gb, bits_left);
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|     next_mb:
 | |
|         mb1 += 6;
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|         block1 += 6 * 64;
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|     }
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| 
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|     /* we need a pass other the whole video segment */
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|     flush_put_bits(&vs_pb);
 | |
|         
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| #ifdef VLC_DEBUG
 | |
|     printf("***pass 3 size=%d\n", vs_bit_count);
 | |
| #endif
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|     block = &s->block[0][0];
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|     mb = mb_data;
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|     init_get_bits(&s->gb, vs_bit_buffer, 5 * 80*8);
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|     for(mb_index = 0; mb_index < 5; mb_index++) {
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|         for(j = 0;j < 6; j++) {
 | |
|             if (!mb->eob_reached) {
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| #ifdef VLC_DEBUG
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|                 printf("start %d:%d\n", mb_index, j);
 | |
| #endif
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|                 dv_decode_ac(s, mb, block, vs_bit_count);
 | |
|             }
 | |
|             block += 64;
 | |
|             mb++;
 | |
|         }
 | |
|     }
 | |
|     
 | |
|     /* compute idct and place blocks */
 | |
|     block = &s->block[0][0];
 | |
|     mb = mb_data;
 | |
|     for(mb_index = 0; mb_index < 5; mb_index++) {
 | |
|         v = *mb_pos_ptr++;
 | |
|         mb_x = v & 0xff;
 | |
|         mb_y = v >> 8;
 | |
|         y_ptr = s->current_picture[0] + (mb_y * s->linesize[0] * 8) + (mb_x * 8);
 | |
|         if (s->sampling_411)
 | |
|             c_offset = (mb_y * s->linesize[1] * 8) + ((mb_x >> 2) * 8);
 | |
|         else
 | |
|             c_offset = ((mb_y >> 1) * s->linesize[1] * 8) + ((mb_x >> 1) * 8);
 | |
|         for(j = 0;j < 6; j++) {
 | |
|             idct_put = s->idct_put[mb->dct_mode];
 | |
|             if (j < 4) {
 | |
|                 if (s->sampling_411 && mb_x < (704 / 8)) {
 | |
|                     /* NOTE: at end of line, the macroblock is handled as 420 */
 | |
|                     idct_put(y_ptr + (j * 8), s->linesize[0], block);
 | |
|                 } else {
 | |
|                     idct_put(y_ptr + ((j & 1) * 8) + ((j >> 1) * 8 * s->linesize[0]),
 | |
|                              s->linesize[0], block);
 | |
|                 }
 | |
|             } else {
 | |
|                 if (s->sampling_411 && mb_x >= (704 / 8)) {
 | |
|                     uint8_t pixels[64], *c_ptr, *c_ptr1, *ptr;
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|                     int y, linesize;
 | |
|                     /* NOTE: at end of line, the macroblock is handled as 420 */
 | |
|                     idct_put(pixels, 8, block);
 | |
|                     linesize = s->linesize[6 - j];
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|                     c_ptr = s->current_picture[6 - j] + c_offset;
 | |
|                     ptr = pixels;
 | |
|                     for(y = 0;y < 8; y++) {
 | |
|                         /* convert to 411P */
 | |
|                         c_ptr1 = c_ptr + 8*linesize;
 | |
|                         c_ptr[0]= ptr[0]; c_ptr1[0]= ptr[4];
 | |
|                         c_ptr[1]= ptr[1]; c_ptr1[1]= ptr[5];
 | |
|                         c_ptr[2]= ptr[2]; c_ptr1[2]= ptr[6];
 | |
|                         c_ptr[3]= ptr[3]; c_ptr1[3]= ptr[7];
 | |
|                         c_ptr += linesize;
 | |
|                         ptr += 8;
 | |
|                     }
 | |
|                 } else {
 | |
|                     /* don't ask me why they inverted Cb and Cr ! */
 | |
|                     idct_put(s->current_picture[6 - j] + c_offset, 
 | |
|                              s->linesize[6 - j], block);
 | |
|                 }
 | |
|             }
 | |
|             block += 64;
 | |
|             mb++;
 | |
|         }
 | |
|     }
 | |
| }
 | |
| 
 | |
| 
 | |
| /* NOTE: exactly one frame must be given (120000 bytes for NTSC,
 | |
|    144000 bytes for PAL) */
 | |
| static int dvvideo_decode_frame(AVCodecContext *avctx, 
 | |
|                                  void *data, int *data_size,
 | |
|                                  uint8_t *buf, int buf_size)
 | |
| {
 | |
|     DVVideoDecodeContext *s = avctx->priv_data;
 | |
|     int sct, dsf, apt, ds, nb_dif_segs, vs, width, height, i, packet_size;
 | |
|     uint8_t *buf_ptr;
 | |
|     const uint16_t *mb_pos_ptr;
 | |
|     
 | |
|     /* parse id */
 | |
|     init_get_bits(&s->gb, buf, buf_size*8);
 | |
|     sct = get_bits(&s->gb, 3);
 | |
|     if (sct != 0)
 | |
|         return -1;
 | |
|     skip_bits(&s->gb, 5);
 | |
|     get_bits(&s->gb, 4); /* dsn (sequence number */
 | |
|     get_bits(&s->gb, 1); /* fsc (channel number) */
 | |
|     skip_bits(&s->gb, 3);
 | |
|     get_bits(&s->gb, 8); /* dbn (diff block number 0-134) */
 | |
| 
 | |
|     dsf = get_bits(&s->gb, 1); /* 0 = NTSC 1 = PAL */
 | |
|     if (get_bits(&s->gb, 1) != 0)
 | |
|         return -1;
 | |
|     skip_bits(&s->gb, 11);
 | |
|     apt = get_bits(&s->gb, 3); /* apt */
 | |
| 
 | |
|     get_bits(&s->gb, 1); /* tf1 */
 | |
|     skip_bits(&s->gb, 4);
 | |
|     get_bits(&s->gb, 3); /* ap1 */
 | |
| 
 | |
|     get_bits(&s->gb, 1); /* tf2 */
 | |
|     skip_bits(&s->gb, 4);
 | |
|     get_bits(&s->gb, 3); /* ap2 */
 | |
| 
 | |
|     get_bits(&s->gb, 1); /* tf3 */
 | |
|     skip_bits(&s->gb, 4);
 | |
|     get_bits(&s->gb, 3); /* ap3 */
 | |
|     
 | |
|     /* init size */
 | |
|     width = 720;
 | |
|     if (dsf) {
 | |
|         avctx->frame_rate = 25;
 | |
| 	avctx->frame_rate_base = 1;
 | |
|         packet_size = PAL_FRAME_SIZE;
 | |
|         height = 576;
 | |
|         nb_dif_segs = 12;
 | |
|     } else {
 | |
|         avctx->frame_rate = 30000;
 | |
| 	avctx->frame_rate_base = 1001;
 | |
|         packet_size = NTSC_FRAME_SIZE;
 | |
|         height = 480;
 | |
|         nb_dif_segs = 10;
 | |
|     }
 | |
|     /* NOTE: we only accept several full frames */
 | |
|     if (buf_size < packet_size)
 | |
|         return -1;
 | |
|     
 | |
|     /* NTSC[dsf == 0] is always 720x480, 4:1:1
 | |
|      *  PAL[dsf == 1] is always 720x576, 4:2:0 for IEC 68134[apt == 0]
 | |
|      *  but for the SMPTE 314M[apt == 1] it is 720x576, 4:1:1
 | |
|      */
 | |
|     s->sampling_411 = !dsf || apt;
 | |
|     if (s->sampling_411) {
 | |
|         mb_pos_ptr = dsf ? dv_place_411P : dv_place_411;
 | |
|         avctx->pix_fmt = PIX_FMT_YUV411P;
 | |
|     } else {
 | |
|         mb_pos_ptr = dv_place_420;
 | |
|         avctx->pix_fmt = PIX_FMT_YUV420P;
 | |
|     }
 | |
| 
 | |
|     avctx->width = width;
 | |
|     avctx->height = height;
 | |
|     
 | |
|     /* Once again, this is pretty complicated by the fact that the same
 | |
|      * field is used differently by IEC 68134[apt == 0] and 
 | |
|      * SMPTE 314M[apt == 1].
 | |
|      */
 | |
|     if (buf[VAUX_TC61_OFFSET] == 0x61 &&
 | |
|         ((apt == 0 && (buf[VAUX_TC61_OFFSET + 2] & 0x07) == 0x07) ||
 | |
| 	 (apt == 1 && (buf[VAUX_TC61_OFFSET + 2] & 0x07) == 0x02)))
 | |
|         avctx->aspect_ratio = 16.0 / 9.0;
 | |
|     else
 | |
|         avctx->aspect_ratio = 4.0 / 3.0;
 | |
| 
 | |
|     if(s->picture.data[0])
 | |
|         avctx->release_buffer(avctx, &s->picture);
 | |
|     
 | |
|     s->picture.reference= 0;
 | |
|     if(avctx->get_buffer(avctx, &s->picture) < 0) {
 | |
|         fprintf(stderr, "get_buffer() failed\n");
 | |
|         return -1;
 | |
|     }
 | |
| 
 | |
|     for(i=0;i<3;i++) {
 | |
|         s->current_picture[i] = s->picture.data[i];
 | |
|         s->linesize[i] = s->picture.linesize[i];
 | |
|         if (!s->current_picture[i])
 | |
|             return -1;
 | |
|     }
 | |
|     s->width = width;
 | |
|     s->height = height;
 | |
| 
 | |
|     /* for each DIF segment */
 | |
|     buf_ptr = buf;
 | |
|     for (ds = 0; ds < nb_dif_segs; ds++) {
 | |
|         buf_ptr += 6 * 80; /* skip DIF segment header */
 | |
|         
 | |
|         for(vs = 0; vs < 27; vs++) {
 | |
|             if ((vs % 3) == 0) {
 | |
|                 /* skip audio block */
 | |
|                 buf_ptr += 80;
 | |
|             }
 | |
|             dv_decode_video_segment(s, buf_ptr, mb_pos_ptr);
 | |
|             buf_ptr += 5 * 80;
 | |
|             mb_pos_ptr += 5;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     emms_c();
 | |
| 
 | |
|     /* return image */
 | |
|     *data_size = sizeof(AVFrame);
 | |
|     *(AVFrame*)data= s->picture;
 | |
|     
 | |
|     return packet_size;
 | |
| }
 | |
| 
 | |
| static int dvvideo_decode_end(AVCodecContext *avctx)
 | |
| {
 | |
|     avcodec_default_free_buffers(avctx);    
 | |
| 
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| AVCodec dvvideo_decoder = {
 | |
|     "dvvideo",
 | |
|     CODEC_TYPE_VIDEO,
 | |
|     CODEC_ID_DVVIDEO,
 | |
|     sizeof(DVVideoDecodeContext),
 | |
|     dvvideo_decode_init,
 | |
|     NULL,
 | |
|     dvvideo_decode_end,
 | |
|     dvvideo_decode_frame,
 | |
|     CODEC_CAP_DR1,
 | |
|     NULL
 | |
| };
 | |
| 
 | |
| typedef struct DVAudioDecodeContext {
 | |
|     AVCodecContext *avctx;
 | |
|     GetBitContext gb;
 | |
| } DVAudioDecodeContext;
 | |
| 
 | |
| static int dvaudio_decode_init(AVCodecContext *avctx)
 | |
| {
 | |
|     //    DVAudioDecodeContext *s = avctx->priv_data;
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| static uint16_t dv_audio_12to16(uint16_t sample)
 | |
| {
 | |
|     uint16_t shift, result;
 | |
|     
 | |
|     sample = (sample < 0x800) ? sample : sample | 0xf000;
 | |
|     shift = (sample & 0xf00) >> 8;
 | |
| 
 | |
|     if (shift < 0x2 || shift > 0xd) {
 | |
| 	result = sample;
 | |
|     } else if (shift < 0x8) {
 | |
|         shift--;
 | |
| 	result = (sample - (256 * shift)) << shift;
 | |
|     } else {
 | |
| 	shift = 0xe - shift;
 | |
| 	result = ((sample + ((256 * shift) + 1)) << shift) - 1;
 | |
|     }
 | |
| 
 | |
|     return result;
 | |
| }
 | |
| 
 | |
| /* NOTE: exactly one frame must be given (120000 bytes for NTSC,
 | |
|    144000 bytes for PAL) 
 | |
| 
 | |
|    There's a couple of assumptions being made here:
 | |
|          1. By default we silence erroneous (0x8000/16bit 0x800/12bit) 
 | |
| 	    audio samples. We can pass them upwards when ffmpeg will be ready
 | |
| 	    to deal with them.
 | |
| 	 2. We don't do software emphasis.
 | |
| 	 3. Audio is always returned as 16bit linear samples: 12bit
 | |
| 	    nonlinear samples are converted into 16bit linear ones.
 | |
| */
 | |
| static int dvaudio_decode_frame(AVCodecContext *avctx, 
 | |
|                                  void *data, int *data_size,
 | |
|                                  uint8_t *buf, int buf_size)
 | |
| {
 | |
|     DVVideoDecodeContext *s = avctx->priv_data;
 | |
|     const uint16_t (*unshuffle)[9];
 | |
|     int smpls, freq, quant, sys, stride, difseg, ad, dp, nb_dif_segs, i;
 | |
|     uint16_t lc, rc;
 | |
|     uint8_t *buf_ptr;
 | |
|     
 | |
|     /* parse id */
 | |
|     init_get_bits(&s->gb, &buf[AAUX_AS_OFFSET], 5*8);
 | |
|     i = get_bits(&s->gb, 8);
 | |
|     if (i != 0x50) { /* No audio ? */
 | |
| 	*data_size = 0;
 | |
| 	return buf_size;
 | |
|     }
 | |
|     
 | |
|     get_bits(&s->gb, 1); /* 0 - locked audio, 1 - unlocked audio */
 | |
|     skip_bits(&s->gb, 1);
 | |
|     smpls = get_bits(&s->gb, 6); /* samples in this frame - min. samples */
 | |
| 
 | |
|     skip_bits(&s->gb, 8);
 | |
| 
 | |
|     skip_bits(&s->gb, 2);
 | |
|     sys = get_bits(&s->gb, 1); /* 0 - 60 fields, 1 = 50 fields */
 | |
|     skip_bits(&s->gb, 5);
 | |
| 
 | |
|     get_bits(&s->gb, 1); /* 0 - emphasis on, 1 - emphasis off */
 | |
|     get_bits(&s->gb, 1); /* 0 - reserved, 1 - emphasis time constant 50/15us */
 | |
|     freq = get_bits(&s->gb, 3); /* 0 - 48KHz, 1 - 44,1kHz, 2 - 32 kHz */
 | |
|     quant = get_bits(&s->gb, 3); /* 0 - 16bit linear, 1 - 12bit nonlinear */
 | |
| 
 | |
|     if (quant > 1)
 | |
| 	return -1; /* Unsupported quantization */
 | |
| 
 | |
|     avctx->sample_rate = dv_audio_frequency[freq];
 | |
|     avctx->channels = 2;
 | |
|     avctx->bit_rate = avctx->channels * avctx->sample_rate * 16;
 | |
|     // What about:
 | |
|     // avctx->frame_size =
 | |
|    
 | |
|     *data_size = (dv_audio_min_samples[sys][freq] + smpls) * 
 | |
| 	         avctx->channels * 2;
 | |
| 
 | |
|     if (sys) {
 | |
| 	nb_dif_segs = 12;
 | |
| 	stride = 108;
 | |
| 	unshuffle = dv_place_audio50;
 | |
|     } else {
 | |
| 	nb_dif_segs = 10;
 | |
| 	stride = 90;
 | |
| 	unshuffle = dv_place_audio60;
 | |
|     }
 | |
|     
 | |
|     /* for each DIF segment */
 | |
|     buf_ptr = buf;
 | |
|     for (difseg = 0; difseg < nb_dif_segs; difseg++) {
 | |
|          buf_ptr += 6 * 80; /* skip DIF segment header */
 | |
|          for (ad = 0; ad < 9; ad++) {
 | |
|               
 | |
|               for (dp = 8; dp < 80; dp+=2) {
 | |
| 		   if (quant == 0) {  /* 16bit quantization */
 | |
| 		       i = unshuffle[difseg][ad] + (dp - 8)/2 * stride;
 | |
| 		       ((short *)data)[i] = (buf_ptr[dp] << 8) | buf_ptr[dp+1]; 
 | |
| 		       if (((unsigned short *)data)[i] == 0x8000)
 | |
| 		           ((short *)data)[i] = 0;
 | |
| 		   } else {           /* 12bit quantization */
 | |
| 		       if (difseg >= nb_dif_segs/2)
 | |
| 			   goto out;  /* We're not doing 4ch at this time */
 | |
| 		       
 | |
| 		       lc = ((uint16_t)buf_ptr[dp] << 4) | 
 | |
| 			    ((uint16_t)buf_ptr[dp+2] >> 4);
 | |
| 		       rc = ((uint16_t)buf_ptr[dp+1] << 4) |
 | |
| 			    ((uint16_t)buf_ptr[dp+2] & 0x0f);
 | |
| 		       lc = (lc == 0x800 ? 0 : dv_audio_12to16(lc));
 | |
| 		       rc = (rc == 0x800 ? 0 : dv_audio_12to16(rc));
 | |
| 
 | |
| 		       i = unshuffle[difseg][ad] + (dp - 8)/3 * stride;
 | |
| 		       ((short *)data)[i] = lc;
 | |
| 		       i = unshuffle[difseg+nb_dif_segs/2][ad] + (dp - 8)/3 * stride;
 | |
| 		       ((short *)data)[i] = rc;
 | |
| 		       ++dp;
 | |
| 		   }
 | |
| 	      }
 | |
| 		
 | |
| 	    buf_ptr += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */
 | |
|         }
 | |
|     }
 | |
| 
 | |
| out:
 | |
|     return buf_size;
 | |
| }
 | |
| 
 | |
| static int dvaudio_decode_end(AVCodecContext *avctx)
 | |
| {
 | |
|     //    DVAudioDecodeContext *s = avctx->priv_data;
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| AVCodec dvaudio_decoder = {
 | |
|     "dvaudio",
 | |
|     CODEC_TYPE_AUDIO,
 | |
|     CODEC_ID_DVAUDIO,
 | |
|     sizeof(DVAudioDecodeContext),
 | |
|     dvaudio_decode_init,
 | |
|     NULL,
 | |
|     dvaudio_decode_end,
 | |
|     dvaudio_decode_frame,
 | |
|     0,
 | |
|     NULL
 | |
| };
 | 
