af_hdcd.c File Reference

HDCD decoding filter. More...

#include "libavutil/opt.h"
#include "libavutil/avassert.h"
#include "avfilter.h"
#include "internal.h"
#include "audio.h"

Classes
struct	hdcd_state
struct	hdcd_detection_data
struct	HDCDContext

Macros
#define	PEAK_EXT_LEVEL   0x5981 /* + sizeof(peaktab)-1 = 0x8000 */
#define	HDCD_PROCESS_STEREO_DEFAULT   1
#define	HDCD_MAX_CHANNELS   2
#define	GAINTOFLOAT(g)   (g) ? -(float)(g>>1) - ((g & 1) ? 0.5 : 0.0) : 0.0
	convert to float from 4-bit (3.1) fixed-point the always-negative value is stored positive, so make it negative
#define	APPLY_GAIN(s, g)   do{int64_t s64 = s; s64 *= gaintab[g]; s = (int32_t)(s64 >> 23); }while(0);
	apply gain, 11-bit (3.8) fixed point, always negative but stored positive. More...
#define	TONEGEN16(sn, f, sr, a)   (int16_t)(sin((6.28318530718 * (sn) * (f)) /(sr)) * (a) * 0x7fff)
	tone generator: sample_number, frequency, sample_rate, amplitude
#define	HDCD_ANA_OFF_DESC   "disabled"
	analyze mode descriptions: macro for AVOption definitions, array of const char for mapping mode to string
#define	HDCD_ANA_LLE_DESC   "gain adjustment level at each sample"
#define	HDCD_ANA_PE_DESC   "samples where peak extend occurs"
#define	HDCD_ANA_CDT_DESC   "samples where the code detect timer is active"
#define	HDCD_ANA_TGM_DESC   "samples where the target gain does not match between channels"
#define	OFFSET(x)   offsetof(HDCDContext, x)
#define	A   AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM

Typedefs
typedef struct hdcd_state	hdcd_state
typedef struct hdcd_detection_data	hdcd_detection_data
typedef struct HDCDContext	HDCDContext

Enumerations
enum	hdcd_pe { HDCD_PE_NEVER = 0, HDCD_PE_INTERMITTENT = 1, HDCD_PE_PERMANENT = 2 }
enum	hdcd_dv { HDCD_NONE = 0, HDCD_NO_EFFECT = 1, HDCD_EFFECTUAL = 2 }
enum	hdcd_pf { HDCD_PVER_NONE = 0, HDCD_PVER_A = 1, HDCD_PVER_B = 2, HDCD_PVER_MIX = 3 }
enum	hdcd_ana_mode {   HDCD_ANA_OFF = 0, HDCD_ANA_LLE = 1, HDCD_ANA_PE = 2, HDCD_ANA_CDT = 3,   HDCD_ANA_TGM = 4, HDCD_ANA_TOP = 5 }
enum	hdcd_control_result { HDCD_OK =0, HDCD_TG_MISMATCH }

Functions
	AVFILTER_DEFINE_CLASS (hdcd)

Variables
AVFilter	ff_af_hdcd

Detailed Description

HDCD decoding filter.

Macro Definition Documentation

APPLY_GAIN

#define APPLY_GAIN	(		s,
			g
	)		do{int64_t s64 = s; s64 *= gaintab[g]; s = (int32_t)(s64 >> 23); }while(0);

apply gain, 11-bit (3.8) fixed point, always negative but stored positive.

Enumeration Type Documentation

hdcd_ana_mode

enum hdcd_ana_mode

Enumerator
HDCD_ANA_TOP	used in max value of AVOption

hdcd_dv

enum hdcd_dv

Enumerator
HDCD_NONE	HDCD packets do not (yet) appear.
HDCD_NO_EFFECT	HDCD packets appear, but all control codes are NOP.
HDCD_EFFECTUAL	HDCD packets appear, and change the output in some way.

hdcd_pe

enum hdcd_pe

Enumerator
HDCD_PE_NEVER	All valid packets have PE set to off.
HDCD_PE_INTERMITTENT	Some valid packets have PE set to on.
HDCD_PE_PERMANENT	All valid packets have PE set to on.

hdcd_pf

enum hdcd_pf

Enumerator
HDCD_PVER_NONE	No packets (yet) discovered.
HDCD_PVER_A	Packets of type A (8-bit control) discovered.
HDCD_PVER_B	Packets of type B (8-bit control, 8-bit XOR) discovered.
HDCD_PVER_MIX	Packets of type A and B discovered, most likely an encoding error.

Variable Documentation

ff_af_hdcd

AVFilter ff_af_hdcd

Initial value:

= {
    .name          = "hdcd",
    .description   = NULL_IF_CONFIG_SMALL("Apply High Definition Compatible Digital (HDCD) decoding."),
    .priv_size     = sizeof(HDCDContext),
    .priv_class    = &hdcd_class,
    .init          = init,
    .uninit        = uninit,
    .query_formats = query_formats,
    .inputs        = avfilter_af_hdcd_inputs,
    .outputs       = avfilter_af_hdcd_outputs,
}