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AC-3 decoder, soc revision 402, Jul 14 13:45:14 2007 UTC by jbr 

merge ac3_decoder.h into ac3_decoder.c

Originally committed as revision 9673 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Justin Ruggles 2007-07-14 16:06:14 +00:00
parent afb46fc092
commit 967d397a6c
1 changed files with 43 additions and 1 deletions
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44
libavcodec/ac3dec.c
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@ -40,10 +40,52 @@
#include "avcodec.h"
#include "ac3tab.h"
#include "ac3_decoder.h"
#include "bitstream.h"
#include "dsputil.h"
static const int nfchans_tbl[8] = { 2, 1, 2, 3, 3, 4, 4, 5 };
/* table for exponent to scale_factor mapping
* scale_factor[i] = 2 ^ -(i + 15)
*/
static float scale_factors[25];
static int16_t psdtab[25];
static int8_t exp_1[128];
static int8_t exp_2[128];
static int8_t exp_3[128];
static int16_t l3_quantizers_1[32];
static int16_t l3_quantizers_2[32];
static int16_t l3_quantizers_3[32];
static int16_t l5_quantizers_1[128];
static int16_t l5_quantizers_2[128];
static int16_t l5_quantizers_3[128];
static int16_t l7_quantizers[7];
static int16_t l11_quantizers_1[128];
static int16_t l11_quantizers_2[128];
static int16_t l15_quantizers[15];
static const uint8_t qntztab[16] = { 0, 5, 7, 3, 7, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 16 };
/* Adjustmens in dB gain */
#define LEVEL_MINUS_3DB 0.7071067811865476
#define LEVEL_MINUS_4POINT5DB 0.5946035575013605
#define LEVEL_MINUS_6DB 0.5000000000000000
#define LEVEL_PLUS_3DB 1.4142135623730951
#define LEVEL_PLUS_6DB 2.0000000000000000
#define LEVEL_ZERO 0.0000000000000000
static const float clevs[4] = { LEVEL_MINUS_3DB, LEVEL_MINUS_4POINT5DB,
LEVEL_MINUS_6DB, LEVEL_MINUS_4POINT5DB };
static const float slevs[4] = { LEVEL_MINUS_3DB, LEVEL_MINUS_6DB, LEVEL_ZERO, LEVEL_MINUS_6DB };
#define N 512 /* constant for IMDCT Block size */
#define MAX_CHANNELS 6