Data Structures | Macros | Typedefs | Functions | Variables
mpegaudiodec.c File Reference

MPEG Audio decoder. More...

#include "libavutil/channel_layout.h"
#include "libavutil/float_dsp.h"
#include "avcodec.h"
#include "get_bits.h"
#include "internal.h"
#include "mathops.h"
#include "mpegaudiodsp.h"
#include "dsputil.h"
#include "mpegaudio.h"
#include "mpegaudiodecheader.h"
#include "mpegaudiodata.h"
#include "mpegaudiodectab.h"
#include "mpegaudio_tablegen.h"

Go to the source code of this file.

Data Structures

struct  GranuleDef
struct  MPADecodeContext

Macros

#define BACKSTEP_SIZE   512
#define EXTRABYTES   24
#define LAST_BUF_SIZE   2 * BACKSTEP_SIZE + EXTRABYTES
#define SHR(a, b)   ((a)>>(b))
#define FIXR_OLD(a)   ((int)((a) * FRAC_ONE + 0.5))
#define FIXR(a)   ((int)((a) * FRAC_ONE + 0.5))
#define FIXHR(a)   ((int)((a) * (1LL<<32) + 0.5))
#define MULH3(x, y, s)   MULH((s)*(x), y)
#define MULLx(x, y, s)   MULL(x,y,s)
#define RENAME(a)   a ## _fixed
#define OUT_FMT   AV_SAMPLE_FMT_S16
#define OUT_FMT_P   AV_SAMPLE_FMT_S16P
#define HEADER_SIZE   4
#define SCALE_GEN(v)   { FIXR_OLD(1.0 * (v)), FIXR_OLD(0.7937005259 * (v)), FIXR_OLD(0.6299605249 * (v)) }
#define C3   FIXHR(0.86602540378443864676/2)
#define C4   FIXHR(0.70710678118654752439/2)
#define C5   FIXHR(0.51763809020504152469/2)
#define C6   FIXHR(1.93185165257813657349/4)
#define SPLIT(dst, sf, n)
#define READ_FLIP_SIGN(dst, src)
#define ISQRT2   FIXR(0.70710678118654752440)
#define AA(j)

Typedefs

typedef struct GranuleDef GranuleDef
typedef struct MPADecodeContext MPADecodeContext

Functions

static void ff_region_offset2size (GranuleDef *g)
 Convert region offsets to region sizes and truncate size to big_values.
static void ff_init_short_region (MPADecodeContext *s, GranuleDef *g)
static void ff_init_long_region (MPADecodeContext *s, GranuleDef *g, int ra1, int ra2)
static void ff_compute_band_indexes (MPADecodeContext *s, GranuleDef *g)
static int l1_unscale (int n, int mant, int scale_factor)
static int l2_unscale_group (int steps, int mant, int scale_factor)
static int l3_unscale (int value, int exponent)
static av_cold void decode_init_static (void)
static av_cold int decode_init (AVCodecContext *avctx)
static void imdct12 (INTFLOAT *out, INTFLOAT *in)
static int mp_decode_layer1 (MPADecodeContext *s)
static int mp_decode_layer2 (MPADecodeContext *s)
static av_always_inline void lsf_sf_expand (int *slen, int sf, int n1, int n2, int n3)
static void exponents_from_scale_factors (MPADecodeContext *s, GranuleDef *g, int16_t *exponents)
static int get_bitsz (GetBitContext *s, int n)
static void switch_buffer (MPADecodeContext *s, int *pos, int *end_pos, int *end_pos2)
static int huffman_decode (MPADecodeContext *s, GranuleDef *g, int16_t *exponents, int end_pos2)
static void reorder_block (MPADecodeContext *s, GranuleDef *g)
static void compute_stereo (MPADecodeContext *s, GranuleDef *g0, GranuleDef *g1)
static void compute_antialias (MPADecodeContext *s, GranuleDef *g)
static void compute_imdct (MPADecodeContext *s, GranuleDef *g, INTFLOAT *sb_samples, INTFLOAT *mdct_buf)
static int mp_decode_layer3 (MPADecodeContext *s)
static int mp_decode_frame (MPADecodeContext *s, OUT_INT **samples, const uint8_t *buf, int buf_size)
static int decode_frame (AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
static void mp_flush (MPADecodeContext *ctx)
static void flush (AVCodecContext *avctx)

Variables

static VLC huff_vlc [16]
static VLC_TYPE huff_vlc_tables [0+128+128+128+130+128+154+166+142+204+190+170+542+460+662+414][2]
static const int huff_vlc_tables_sizes [16]
static VLC huff_quad_vlc [2]
static VLC_TYPE huff_quad_vlc_tables [128+16][2]
static const int huff_quad_vlc_tables_sizes [2] = { 128, 16 }
static uint16_t band_index_long [9][23]
static INTFLOAT is_table [2][16]
static INTFLOAT is_table_lsf [2][2][16]
static INTFLOAT csa_table [8][4]
static int16_t division_tab3 [1<< 6]
static int16_t division_tab5 [1<< 8]
static int16_t division_tab9 [1<< 11]
static int16_t *const division_tabs [4]
static uint16_t scale_factor_modshift [64]
static int32_t scale_factor_mult [15][3]
static const int32_t scale_factor_mult2 [3][3]

Detailed Description

MPEG Audio decoder.

Definition in file mpegaudiodec.c.

Macro Definition Documentation

#define AA (   j)
Value:
do { \
int tmp0 = ptr[-1-j]; \
int tmp1 = ptr[ j]; \
int tmp2 = MULH(tmp0 + tmp1, csa_table[j][0]); \
ptr[-1-j] = 4 * (tmp2 - MULH(tmp1, csa_table[j][2])); \
ptr[ j] = 4 * (tmp2 + MULH(tmp0, csa_table[j][3])); \
} while (0)

Definition at line 1183 of file mpegaudiodec.c.

Referenced by compute_antialias().

#define BACKSTEP_SIZE   512

Definition at line 44 of file mpegaudiodec.c.

Referenced by mp_decode_frame().

#define C3   FIXHR(0.86602540378443864676/2)

Definition at line 457 of file mpegaudiodec.c.

Referenced by imdct12().

#define C4   FIXHR(0.70710678118654752439/2)

Definition at line 458 of file mpegaudiodec.c.

Referenced by imdct12().

#define C5   FIXHR(0.51763809020504152469/2)

Definition at line 459 of file mpegaudiodec.c.

Referenced by imdct12().

#define C6   FIXHR(1.93185165257813657349/4)

Definition at line 460 of file mpegaudiodec.c.

Referenced by imdct12().

#define EXTRABYTES   24

Definition at line 45 of file mpegaudiodec.c.

#define FIXHR (   a)    ((int)((a) * (1LL<<32) + 0.5))

Definition at line 105 of file mpegaudiodec.c.

Referenced by decode_init_static().

#define FIXR (   a)    ((int)((a) * FRAC_ONE + 0.5))

Definition at line 104 of file mpegaudiodec.c.

Referenced by decode_init_static().

#define FIXR_OLD (   a)    ((int)((a) * FRAC_ONE + 0.5))

Definition at line 103 of file mpegaudiodec.c.

#define HEADER_SIZE   4

Definition at line 115 of file mpegaudiodec.c.

Referenced by decode_frame(), and mp_decode_frame().

#define ISQRT2   FIXR(0.70710678118654752440)

Definition at line 1045 of file mpegaudiodec.c.

Referenced by compute_stereo().

#define LAST_BUF_SIZE   2 * BACKSTEP_SIZE + EXTRABYTES

Definition at line 46 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

#define MULH3 (   x,
  y,
  s 
)    MULH((s)*(x), y)

Definition at line 106 of file mpegaudiodec.c.

Referenced by compute_imdct(), and imdct12().

#define MULLx (   x,
  y,
  s 
)    MULL(x,y,s)

Definition at line 107 of file mpegaudiodec.c.

Referenced by compute_stereo(), and decode_init_static().

#define OUT_FMT   AV_SAMPLE_FMT_S16

Definition at line 109 of file mpegaudiodec.c.

Referenced by decode_init().

#define OUT_FMT_P   AV_SAMPLE_FMT_S16P

Definition at line 110 of file mpegaudiodec.c.

Referenced by decode_init(), and mp_decode_frame().

#define READ_FLIP_SIGN (   dst,
  src 
)
Value:
v = -get_bits1(&s->gb); \
*(dst) = (*(src) ^ v) - v;

Definition at line 856 of file mpegaudiodec.c.

Referenced by huffman_decode().

#define RENAME (   a)    a ## _fixed

Definition at line 108 of file mpegaudiodec.c.

Referenced by compute_imdct(), decode_init_static(), huffman_decode(), mp_decode_frame(), rgb2rgb_init(), sws_init_swScale(), uyvytoyuv420(), uyvytoyuv422(), yuv422ptouyvy(), yuv422ptoyuy2(), yuyvtoyuv420(), yuyvtoyuv422(), yv12touyvy(), and yv12toyuy2().

#define SCALE_GEN (   v)    { FIXR_OLD(1.0 * (v)), FIXR_OLD(0.7937005259 * (v)), FIXR_OLD(0.6299605249 * (v)) }

Definition at line 155 of file mpegaudiodec.c.

#define SHR (   a,
  b 
)    ((a)>>(b))

Definition at line 101 of file mpegaudiodec.c.

Referenced by imdct12().

#define SPLIT (   dst,
  sf,
  n 
)
Value:
if (n == 3) { \
int m = (sf * 171) >> 9; \
dst = sf - 3 * m; \
sf = m; \
} else if (n == 4) { \
dst = sf & 3; \
sf >>= 2; \
} else if (n == 5) { \
int m = (sf * 205) >> 10; \
dst = sf - 5 * m; \
sf = m; \
} else if (n == 6) { \
int m = (sf * 171) >> 10; \
dst = sf - 6 * m; \
sf = m; \
} else { \
dst = 0; \
}

Definition at line 758 of file mpegaudiodec.c.

Referenced by avfilter_register_all(), and lsf_sf_expand().

Typedef Documentation

typedef struct GranuleDef GranuleDef
typedef struct MPADecodeContext MPADecodeContext

Function Documentation

static void compute_antialias ( MPADecodeContext *  s,
GranuleDef *  g 
)
static

Definition at line 1192 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

static void compute_imdct ( MPADecodeContext *  s,
GranuleDef *  g,
INTFLOAT *  sb_samples,
INTFLOAT *  mdct_buf 
)
static

Definition at line 1222 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

static void compute_stereo ( MPADecodeContext *  s,
GranuleDef *  g0,
GranuleDef *  g1 
)
static

Definition at line 1047 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

static int decode_frame ( AVCodecContext *  avctx,
void *  data,
int *  got_frame_ptr,
AVPacket *  avpkt 
)
static

Definition at line 1646 of file mpegaudiodec.c.

static av_cold int decode_init ( AVCodecContext *  avctx)
static

Definition at line 426 of file mpegaudiodec.c.

static av_cold void decode_init_static ( void  )
static

Definition at line 277 of file mpegaudiodec.c.

Referenced by decode_init().

static void exponents_from_scale_factors ( MPADecodeContext *  s,
GranuleDef *  g,
int16_t *  exponents 
)
static

Definition at line 787 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

static void ff_compute_band_indexes ( MPADecodeContext *  s,
GranuleDef *  g 
)
static

Definition at line 206 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

static void ff_init_long_region ( MPADecodeContext *  s,
GranuleDef *  g,
int  ra1,
int  ra2 
)
static

Definition at line 197 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

static void ff_init_short_region ( MPADecodeContext *  s,
GranuleDef *  g 
)
static

Definition at line 179 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

static void ff_region_offset2size ( GranuleDef *  g)
static

Convert region offsets to region sizes and truncate size to big_values.

Definition at line 168 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

static void flush ( AVCodecContext *  avctx)
static

Definition at line 1709 of file mpegaudiodec.c.

static int get_bitsz ( GetBitContext *  s,
int  n 
)
inlinestatic

Definition at line 825 of file mpegaudiodec.c.

Referenced by huffman_decode().

static int huffman_decode ( MPADecodeContext *  s,
GranuleDef *  g,
int16_t *  exponents,
int  end_pos2 
)
static

Definition at line 861 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

static void imdct12 ( INTFLOAT *  out,
INTFLOAT *  in 
)
static

Definition at line 464 of file mpegaudiodec.c.

Referenced by compute_imdct().

static int l1_unscale ( int  n,
int  mant,
int  scale_factor 
)
inlinestatic

Definition at line 231 of file mpegaudiodec.c.

Referenced by mp_decode_layer1(), and mp_decode_layer2().

static int l2_unscale_group ( int  steps,
int  mant,
int  scale_factor 
)
inlinestatic

Definition at line 245 of file mpegaudiodec.c.

Referenced by mp_decode_layer2().

static int l3_unscale ( int  value,
int  exponent 
)
inlinestatic

Definition at line 261 of file mpegaudiodec.c.

Referenced by huffman_decode().

static av_always_inline void lsf_sf_expand ( int *  slen,
int  sf,
int  n1,
int  n2,
int  n3 
)
static

Definition at line 778 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

static int mp_decode_frame ( MPADecodeContext *  s,
OUT_INT **  samples,
const uint8_t *  buf,
int  buf_size 
)
static

Definition at line 1557 of file mpegaudiodec.c.

Referenced by decode_frame().

static int mp_decode_layer1 ( MPADecodeContext *  s)
static

Definition at line 506 of file mpegaudiodec.c.

Referenced by mp_decode_frame().

static int mp_decode_layer2 ( MPADecodeContext *  s)
static

Definition at line 571 of file mpegaudiodec.c.

Referenced by mp_decode_frame().

static int mp_decode_layer3 ( MPADecodeContext *  s)
static

Definition at line 1302 of file mpegaudiodec.c.

Referenced by mp_decode_frame().

static void mp_flush ( MPADecodeContext *  ctx)
static

Definition at line 1703 of file mpegaudiodec.c.

Referenced by flush().

static void reorder_block ( MPADecodeContext *  s,
GranuleDef *  g 
)
static

Definition at line 1012 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

static void switch_buffer ( MPADecodeContext *  s,
int *  pos,
int *  end_pos,
int *  end_pos2 
)
static

Definition at line 831 of file mpegaudiodec.c.

Referenced by huffman_decode().

Variable Documentation

uint16_t band_index_long[9][23]
static

Definition at line 134 of file mpegaudiodec.c.

Referenced by decode_init_static(), and ff_init_long_region().

INTFLOAT csa_table[8][4]
static

Definition at line 139 of file mpegaudiodec.c.

Referenced by decode_init_static().

int16_t division_tab3[1<< 6]
static

Definition at line 141 of file mpegaudiodec.c.

int16_t division_tab5[1<< 8]
static

Definition at line 142 of file mpegaudiodec.c.

int16_t division_tab9[1<< 11]
static

Definition at line 143 of file mpegaudiodec.c.

int16_t* const division_tabs[4]
static
Initial value:
{
division_tab3, division_tab5, NULL, division_tab9
}

Definition at line 145 of file mpegaudiodec.c.

Referenced by decode_init_static(), and mp_decode_layer2().

VLC huff_quad_vlc[2]
static

Definition at line 130 of file mpegaudiodec.c.

VLC_TYPE huff_quad_vlc_tables[128+16][2]
static

Definition at line 131 of file mpegaudiodec.c.

Referenced by decode_init_static().

const int huff_quad_vlc_tables_sizes[2] = { 128, 16 }
static

Definition at line 132 of file mpegaudiodec.c.

Referenced by decode_init_static().

VLC huff_vlc[16]
static

Definition at line 121 of file mpegaudiodec.c.

VLC_TYPE huff_vlc_tables[0+128+128+128+130+128+154+166+142+204+190+170+542+460+662+414][2]
static

Definition at line 125 of file mpegaudiodec.c.

Referenced by decode_init_static().

const int huff_vlc_tables_sizes[16]
static
Initial value:
{
0, 128, 128, 128, 130, 128, 154, 166,
142, 204, 190, 170, 542, 460, 662, 414
}

Definition at line 126 of file mpegaudiodec.c.

Referenced by decode_init_static().

INTFLOAT is_table[2][16]
static

Definition at line 137 of file mpegaudiodec.c.

Referenced by compute_stereo(), and decode_init_static().

INTFLOAT is_table_lsf[2][2][16]
static

Definition at line 138 of file mpegaudiodec.c.

Referenced by compute_stereo(), and decode_init_static().

uint16_t scale_factor_modshift[64]
static

Definition at line 150 of file mpegaudiodec.c.

Referenced by decode_init_static(), l1_unscale(), and l2_unscale_group().

int32_t scale_factor_mult[15][3]
static

Definition at line 152 of file mpegaudiodec.c.

Referenced by decode_init_static(), encode_frame(), l1_unscale(), and MPA_encode_init().

const int32_t scale_factor_mult2[3][3]
static
Initial value:
{
SCALE_GEN(4.0 / 3.0),
SCALE_GEN(4.0 / 5.0),
SCALE_GEN(4.0 / 9.0),
}

Definition at line 158 of file mpegaudiodec.c.

Referenced by l2_unscale_group().