MPEG Audio decoder. More...

#include "libavutil/attributes.h"
#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"

Data Structures
struct	GranuleDef

struct	MPADecodeContext

Macros
#define	BACKSTEP_SIZE 512

#define	EXTRABYTES 24

#define	LAST_BUF_SIZE 2 * BACKSTEP_SIZE + EXTRABYTES

#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)

Functions
static void	region_offset2size (GranuleDef *g)
	Convert region offsets to region sizes and truncate size to big_values. More...

static void	init_short_region (MPADecodeContext s, GranuleDef g)

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

static void	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, SUINTFLOAT 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 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_template.c.

Macro Definition Documentation

◆ BACKSTEP_SIZE

#define BACKSTEP_SIZE 512

Definition at line 46 of file mpegaudiodec_template.c.

Referenced by mp_decode_frame().

◆ EXTRABYTES

#define EXTRABYTES 24

Definition at line 47 of file mpegaudiodec_template.c.

◆ LAST_BUF_SIZE

#define LAST_BUF_SIZE 2 * BACKSTEP_SIZE + EXTRABYTES

Definition at line 48 of file mpegaudiodec_template.c.

Referenced by mp_decode_layer3().

◆ HEADER_SIZE

#define HEADER_SIZE 4

Definition at line 93 of file mpegaudiodec_template.c.

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

◆ SCALE_GEN

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

Definition at line 133 of file mpegaudiodec_template.c.

◆ C3

#define C3 FIXHR(0.86602540378443864676/2)

Definition at line 454 of file mpegaudiodec_template.c.

Referenced by imdct12().

◆ C4

#define C4 FIXHR(0.70710678118654752439/2)

Definition at line 455 of file mpegaudiodec_template.c.

Referenced by imdct12().

◆ C5

#define C5 FIXHR(0.51763809020504152469/2)

Definition at line 456 of file mpegaudiodec_template.c.

Referenced by imdct12().

◆ C6

#define C6 FIXHR(1.93185165257813657349/4)

Definition at line 457 of file mpegaudiodec_template.c.

Referenced by imdct12().

◆ SPLIT

#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 755 of file mpegaudiodec_template.c.

Referenced by lsf_sf_expand().

◆ READ_FLIP_SIGN

#define READ_FLIP_SIGN	(	dst,
		src
	)

Value:

v = -get_bits1(&s->gb); \

*(dst) = (*(src) ^ v) - v;

s

const char * s

Definition: avisynth_c.h:768

src

#define src

Definition: vp8dsp.c:254

get_bits1

static unsigned int get_bits1(GetBitContext *s)

Definition: get_bits.h:321

Definition at line 847 of file mpegaudiodec_template.c.

Referenced by huffman_decode().

◆ ISQRT2

#define ISQRT2 FIXR(0.70710678118654752440)

Definition at line 1036 of file mpegaudiodec_template.c.

Referenced by compute_stereo().

◆ AA

#define AA ( j )

Value:

do {                                              \
        SUINT tmp0 = ptr[-1-j];                                   \
        SUINT tmp1 = ptr[   j];                                   \
        SUINT 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 1186 of file mpegaudiodec_template.c.

Referenced by compute_antialias().

Function Documentation

◆ region_offset2size()

static void region_offset2size ( GranuleDef * g )

static

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

Definition at line 146 of file mpegaudiodec_template.c.

Referenced by mp_decode_layer3().

◆ init_short_region()

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

static

Definition at line 157 of file mpegaudiodec_template.c.

Referenced by mp_decode_layer3().

◆ init_long_region()

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

static

Definition at line 175 of file mpegaudiodec_template.c.

Referenced by mp_decode_layer3().

◆ compute_band_indexes()

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

static

Definition at line 185 of file mpegaudiodec_template.c.

Referenced by mp_decode_layer3().

◆ l1_unscale()

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

inlinestatic

Definition at line 212 of file mpegaudiodec_template.c.

Referenced by mp_decode_layer1(), and mp_decode_layer2().

◆ l2_unscale_group()

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

inlinestatic

Definition at line 226 of file mpegaudiodec_template.c.

Referenced by mp_decode_layer2().

◆ l3_unscale()

static int l3_unscale	(	int	value,
		int	exponent
	)

inlinestatic

Definition at line 242 of file mpegaudiodec_template.c.

Referenced by huffman_decode().

◆ decode_init_static()

static av_cold void decode_init_static ( void )

static

Definition at line 261 of file mpegaudiodec_template.c.

Referenced by decode_init().

◆ decode_init()

static av_cold int decode_init ( AVCodecContext * avctx )

static

Definition at line 421 of file mpegaudiodec_template.c.

Referenced by flush().

◆ imdct12()

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

static

Definition at line 461 of file mpegaudiodec_template.c.

Referenced by compute_imdct().

◆ mp_decode_layer1()

static int mp_decode_layer1 ( MPADecodeContext * s )

static

Definition at line 503 of file mpegaudiodec_template.c.

Referenced by mp_decode_frame().

◆ mp_decode_layer2()

static int mp_decode_layer2 ( MPADecodeContext * s )

static

Definition at line 568 of file mpegaudiodec_template.c.

Referenced by mp_decode_frame().

◆ lsf_sf_expand()

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

static

Definition at line 775 of file mpegaudiodec_template.c.

Referenced by mp_decode_layer3().

◆ exponents_from_scale_factors()

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

static

Definition at line 784 of file mpegaudiodec_template.c.

Referenced by mp_decode_layer3().

◆ switch_buffer()

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

static

Definition at line 821 of file mpegaudiodec_template.c.

Referenced by huffman_decode().

◆ huffman_decode()

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

static

Definition at line 852 of file mpegaudiodec_template.c.

Referenced by mp_decode_layer3().

◆ reorder_block()

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

static

Definition at line 1003 of file mpegaudiodec_template.c.

Referenced by mp_decode_layer3().

◆ compute_stereo()

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

static

Definition at line 1038 of file mpegaudiodec_template.c.

Referenced by mp_decode_layer3().

◆ compute_antialias()

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

static

Definition at line 1195 of file mpegaudiodec_template.c.

Referenced by mp_decode_layer3().

◆ compute_imdct()

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

static

Definition at line 1226 of file mpegaudiodec_template.c.

Referenced by mp_decode_layer3().

◆ mp_decode_layer3()

static int mp_decode_layer3 ( MPADecodeContext * s )

static

Definition at line 1306 of file mpegaudiodec_template.c.

Referenced by mp_decode_frame().

◆ mp_decode_frame()

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

static

Definition at line 1560 of file mpegaudiodec_template.c.

Referenced by decode_frame(), and flush().

◆ decode_frame()

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

static

Definition at line 1648 of file mpegaudiodec_template.c.

◆ mp_flush()

static void mp_flush ( MPADecodeContext * ctx )

static

Definition at line 1718 of file mpegaudiodec_template.c.

Referenced by flush().

◆ flush()

static void flush ( AVCodecContext * avctx )

static

Definition at line 1726 of file mpegaudiodec_template.c.

Variable Documentation

◆ huff_vlc

VLC huff_vlc[16]

static

Definition at line 99 of file mpegaudiodec_template.c.

◆ huff_vlc_tables

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 103 of file mpegaudiodec_template.c.

Referenced by decode_init_static().

◆ huff_vlc_tables_sizes

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 104 of file mpegaudiodec_template.c.

Referenced by decode_init_static().

◆ huff_quad_vlc

VLC huff_quad_vlc[2]

static

Definition at line 108 of file mpegaudiodec_template.c.

◆ huff_quad_vlc_tables

VLC_TYPE huff_quad_vlc_tables[128+16][2]

static

Definition at line 109 of file mpegaudiodec_template.c.

Referenced by decode_init_static().

◆ huff_quad_vlc_tables_sizes

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

static

Definition at line 110 of file mpegaudiodec_template.c.

Referenced by decode_init_static().

◆ band_index_long

uint16_t band_index_long[9][23]

static

Definition at line 112 of file mpegaudiodec_template.c.

Referenced by decode_init_static(), and init_long_region().

◆ is_table

INTFLOAT is_table[2][16]

static

Definition at line 115 of file mpegaudiodec_template.c.

Referenced by compute_stereo(), and decode_init_static().

◆ is_table_lsf

INTFLOAT is_table_lsf[2][2][16]

static

Definition at line 116 of file mpegaudiodec_template.c.

Referenced by compute_stereo(), and decode_init_static().

◆ csa_table

INTFLOAT csa_table[8][4]

static

Definition at line 117 of file mpegaudiodec_template.c.

Referenced by decode_init_static().

◆ division_tab3

int16_t division_tab3[1<< 6]

static

Definition at line 119 of file mpegaudiodec_template.c.

◆ division_tab5

int16_t division_tab5[1<< 8]

static

Definition at line 120 of file mpegaudiodec_template.c.

◆ division_tab9

int16_t division_tab9[1<< 11]

static

Definition at line 121 of file mpegaudiodec_template.c.

◆ division_tabs

int16_t* const division_tabs[4]

static

Initial value:

= {
    division_tab3, division_tab5, NULL, division_tab9
}

Definition at line 123 of file mpegaudiodec_template.c.

Referenced by decode_init_static(), and mp_decode_layer2().

◆ scale_factor_modshift

uint16_t scale_factor_modshift[64]

static

Definition at line 128 of file mpegaudiodec_template.c.

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

◆ scale_factor_mult

int32_t scale_factor_mult[15][3]

static

Definition at line 130 of file mpegaudiodec_template.c.

Referenced by decode_init_static(), and l1_unscale().

◆ scale_factor_mult2

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 136 of file mpegaudiodec_template.c.

Referenced by l2_unscale_group().

Data Structures

Macros

Functions

Variables

Detailed Description

Macro Definition Documentation

◆ BACKSTEP_SIZE

◆ EXTRABYTES

◆ LAST_BUF_SIZE

◆ HEADER_SIZE

◆ SCALE_GEN

◆ C3

◆ C4

◆ C5

◆ C6

◆ SPLIT

◆ READ_FLIP_SIGN

◆ ISQRT2

◆ AA

Function Documentation

◆ region_offset2size()

◆ init_short_region()

◆ init_long_region()

◆ compute_band_indexes()

◆ l1_unscale()

◆ l2_unscale_group()

◆ l3_unscale()

◆ decode_init_static()

◆ decode_init()

◆ imdct12()

◆ mp_decode_layer1()

◆ mp_decode_layer2()

◆ lsf_sf_expand()

◆ exponents_from_scale_factors()

◆ switch_buffer()

◆ huffman_decode()

◆ reorder_block()

◆ compute_stereo()

◆ compute_antialias()

◆ compute_imdct()

◆ mp_decode_layer3()

◆ mp_decode_frame()

◆ decode_frame()

◆ mp_flush()

◆ flush()

Variable Documentation

◆ huff_vlc

◆ huff_vlc_tables

◆ huff_vlc_tables_sizes

◆ huff_quad_vlc

◆ huff_quad_vlc_tables

◆ huff_quad_vlc_tables_sizes

◆ band_index_long

◆ is_table

◆ is_table_lsf

◆ csa_table

◆ division_tab3

◆ division_tab5

◆ division_tab9

◆ division_tabs

◆ scale_factor_modshift

◆ scale_factor_mult

◆ scale_factor_mult2