mpegaudiodec.c File Reference

MPEG Audio decoder. More...

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

Include dependency graph for mpegaudiodec.c:

This graph shows which files directly or indirectly include this file:

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. More...
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 1197 of file mpegaudiodec.c.

Referenced by compute_antialias().

#define BACKSTEP_SIZE   512

Definition at line 45 of file mpegaudiodec.c.

Referenced by mp_decode_frame().

#define C3   FIXHR(0.86602540378443864676/2)

Definition at line 460 of file mpegaudiodec.c.

Referenced by __attribute__(), and imdct12().

#define C4   FIXHR(0.70710678118654752439/2)

Definition at line 461 of file mpegaudiodec.c.

Referenced by __attribute__(), and imdct12().

#define C5   FIXHR(0.51763809020504152469/2)

Definition at line 462 of file mpegaudiodec.c.

Referenced by __attribute__(), and imdct12().

#define C6   FIXHR(1.93185165257813657349/4)

Definition at line 463 of file mpegaudiodec.c.

Referenced by imdct12().

#define EXTRABYTES   24

Definition at line 46 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

#define FIXHR

(

a

)

((int)((a) * (1LL<<32) + 0.5))

Definition at line 106 of file mpegaudiodec.c.

Referenced by decode_init_static().

#define FIXR

(

a

)

((int)((a) * FRAC_ONE + 0.5))

Definition at line 105 of file mpegaudiodec.c.

Referenced by decode_init_static().

#define FIXR_OLD

(

a

)

((int)((a) * FRAC_ONE + 0.5))

Definition at line 104 of file mpegaudiodec.c.

#define HEADER_SIZE   4

Definition at line 116 of file mpegaudiodec.c.

Referenced by decode_frame(), flush(), and mp_decode_frame().

#define ISQRT2   FIXR(0.70710678118654752440)

Definition at line 1048 of file mpegaudiodec.c.

Referenced by compute_stereo().

#define LAST_BUF_SIZE   2 * BACKSTEP_SIZE + EXTRABYTES

Definition at line 47 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

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

Definition at line 107 of file mpegaudiodec.c.

Referenced by compute_imdct(), and imdct12().

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

Definition at line 108 of file mpegaudiodec.c.

Referenced by compute_stereo(), and decode_init_static().

#define OUT_FMT   AV_SAMPLE_FMT_S16

Definition at line 110 of file mpegaudiodec.c.

Referenced by decode_init().

#define OUT_FMT_P   AV_SAMPLE_FMT_S16P

Definition at line 111 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 859 of file mpegaudiodec.c.

Referenced by huffman_decode().

#define RENAME

(

a

)

a ## _fixed

Definition at line 109 of file mpegaudiodec.c.

Referenced by compute_imdct(), decode_init_static(), deInterlaceMedian(), huffman_decode(), mp_decode_frame(), postProcess(), rgb2rgb_init(), sws_init_swScale(), tempNoiseReducer(), uyvytoyuv420(), uyvytoyuv422(), uyvytoyv12(), yuv2yuyv422_1(), yuv420_bgr32(), yuv420_rgb32(), yuv422ptouyvy(), yuv422ptoyuy2(), yuy2toyv12(), 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 156 of file mpegaudiodec.c.

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

Definition at line 102 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 761 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 1206 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 1237 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

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

static

Definition at line 1050 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 1659 of file mpegaudiodec.c.

Referenced by flush().

static av_cold int decode_init ( AVCodecContext *  avctx )

static

Definition at line 432 of file mpegaudiodec.c.

Referenced by flush().

static av_cold void decode_init_static ( void  )

static

Definition at line 283 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 790 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

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

static

Definition at line 207 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 198 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

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

static

Definition at line 180 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 169 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

static void flush ( AVCodecContext *  avctx )

static

Definition at line 1734 of file mpegaudiodec.c.

static int get_bitsz ( GetBitContext *  s, int  n  )

inlinestatic

Definition at line 828 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 864 of file mpegaudiodec.c.

Referenced by mp_decode_layer3().

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

static

Definition at line 467 of file mpegaudiodec.c.

Referenced by compute_imdct().

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

inlinestatic

Definition at line 234 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 248 of file mpegaudiodec.c.

Referenced by mp_decode_layer2().

static int l3_unscale ( int  value, int  exponent  )

inlinestatic

Definition at line 264 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 781 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 1571 of file mpegaudiodec.c.

Referenced by decode_frame(), and flush().

static int mp_decode_layer1 ( MPADecodeContext *  s )

static

Definition at line 509 of file mpegaudiodec.c.

Referenced by mp_decode_frame().

static int mp_decode_layer2 ( MPADecodeContext *  s )

static

Definition at line 574 of file mpegaudiodec.c.

Referenced by mp_decode_frame().

static int mp_decode_layer3 ( MPADecodeContext *  s )

static

Definition at line 1317 of file mpegaudiodec.c.

Referenced by mp_decode_frame().

static void mp_flush ( MPADecodeContext *  ctx )

static

Definition at line 1728 of file mpegaudiodec.c.

Referenced by flush().

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

static

Definition at line 1015 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 834 of file mpegaudiodec.c.

Referenced by huffman_decode().

Variable Documentation

uint16_t band_index_long[9][23]

static

Definition at line 135 of file mpegaudiodec.c.

Referenced by decode_init_static(), and ff_init_long_region().

INTFLOAT csa_table[8][4]

static

Definition at line 140 of file mpegaudiodec.c.

Referenced by decode_init_static().

int16_t division_tab3[1<< 6]

static

Definition at line 142 of file mpegaudiodec.c.

int16_t division_tab5[1<< 8]

static

Definition at line 143 of file mpegaudiodec.c.

int16_t division_tab9[1<< 11]

static

Definition at line 144 of file mpegaudiodec.c.

int16_t* const division_tabs[4]

static

Initial value:

= {
    division_tab3, division_tab5, NULL, division_tab9
}

Definition at line 146 of file mpegaudiodec.c.

Referenced by decode_init_static(), and mp_decode_layer2().

VLC huff_quad_vlc[2]

static

Definition at line 131 of file mpegaudiodec.c.

VLC_TYPE huff_quad_vlc_tables[128+16][2]

static

Definition at line 132 of file mpegaudiodec.c.

Referenced by decode_init_static().

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

static

Definition at line 133 of file mpegaudiodec.c.

Referenced by decode_init_static().

VLC huff_vlc[16]

static

Definition at line 122 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 126 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 127 of file mpegaudiodec.c.

Referenced by decode_init_static().

INTFLOAT is_table[2][16]

static

Definition at line 138 of file mpegaudiodec.c.

Referenced by compute_stereo(), and decode_init_static().

INTFLOAT is_table_lsf[2][2][16]

static

Definition at line 139 of file mpegaudiodec.c.

Referenced by compute_stereo(), and decode_init_static().

uint16_t scale_factor_modshift[64]

static

Definition at line 151 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 153 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 159 of file mpegaudiodec.c.

Referenced by l2_unscale_group().