libavcodec/mpegaudioenc.c File Reference

The simplest mpeg audio layer 2 encoder. More...

#include "libavutil/audioconvert.h"
#include "avcodec.h"
#include "internal.h"
#include "put_bits.h"
#include "mpegaudio.h"
#include "mpegaudiodsp.h"
#include "mpegaudiodata.h"
#include "mpegaudiotab.h"

Go to the source code of this file.

Data Structures
struct	MpegAudioContext
Defines
#define	FRAC_BITS   15
#define	WFRAC_BITS   14
#define	MUL(a, b)   (((int64_t)(a) * (int64_t)(b)) >> FRAC_BITS)
#define	SAMPLES_BUF_SIZE   4096
#define	USE_FLOATS
#define	WSHIFT   (WFRAC_BITS + 15 - FRAC_BITS)
#define	SB_NOTALLOCATED   0
#define	SB_ALLOCATED   1
#define	SB_NOMORE   2
Functions
static av_cold int	MPA_encode_init (AVCodecContext *avctx)
static void	idct32 (int *out, int *tab)
static void	filter (MpegAudioContext *s, int ch, const short *samples, int incr)
static void	compute_scale_factors (unsigned char scale_code[SBLIMIT], unsigned char scale_factors[SBLIMIT][3], int sb_samples[3][12][SBLIMIT], int sblimit)
static void	psycho_acoustic_model (MpegAudioContext *s, short smr[SBLIMIT])
static void	compute_bit_allocation (MpegAudioContext *s, short smr1[MPA_MAX_CHANNELS][SBLIMIT], unsigned char bit_alloc[MPA_MAX_CHANNELS][SBLIMIT], int *padding)
static void	encode_frame (MpegAudioContext *s, unsigned char bit_alloc[MPA_MAX_CHANNELS][SBLIMIT], int padding)
static int	MPA_encode_frame (AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
static av_cold int	MPA_encode_close (AVCodecContext *avctx)
Variables
static const AVCodecDefault	mp2_defaults []
AVCodec	ff_mp2_encoder

---

Detailed Description

The simplest mpeg audio layer 2 encoder.

Definition in file mpegaudioenc.c.

---

Define Documentation

#define FRAC_BITS   15

Definition at line 33 of file mpegaudioenc.c.

#define MUL	(	a,
		b		)	(((int64_t)(a) * (int64_t)(b)) >> FRAC_BITS)

Definition at line 41 of file mpegaudioenc.c.

Referenced by idct32(), and idctRowCondDC().

#define SAMPLES_BUF_SIZE   4096

Definition at line 43 of file mpegaudioenc.c.

Referenced by filter().

#define SB_ALLOCATED   1

Definition at line 497 of file mpegaudioenc.c.

Referenced by compute_bit_allocation().

#define SB_NOMORE   2

Definition at line 498 of file mpegaudioenc.c.

Referenced by compute_bit_allocation().

#define SB_NOTALLOCATED   0

Definition at line 496 of file mpegaudioenc.c.

Referenced by compute_bit_allocation().

#define USE_FLOATS

Definition at line 65 of file mpegaudioenc.c.

#define WFRAC_BITS   14

Definition at line 34 of file mpegaudioenc.c.

#define WSHIFT   (WFRAC_BITS + 15 - FRAC_BITS)

Definition at line 316 of file mpegaudioenc.c.

Referenced by filter().

---

Function Documentation

static void compute_bit_allocation	(	MpegAudioContext *	s,
		short	smr1[MPA_MAX_CHANNELS][SBLIMIT],
		unsigned char	bit_alloc[MPA_MAX_CHANNELS][SBLIMIT],
		int *	padding
	)			[static]

Definition at line 503 of file mpegaudioenc.c.

Referenced by MPA_encode_frame().

static void compute_scale_factors	(	unsigned char	scale_code[SBLIMIT],
		unsigned char	scale_factors[SBLIMIT][3],
		int	sb_samples[3][12][SBLIMIT],
		int	sblimit
	)			[static]

Definition at line 371 of file mpegaudioenc.c.

Referenced by MPA_encode_frame().

static void encode_frame	(	MpegAudioContext *	s,
		unsigned char	bit_alloc[MPA_MAX_CHANNELS][SBLIMIT],
		int	padding
	)			[static]

Definition at line 599 of file mpegaudioenc.c.

static void filter	(	MpegAudioContext *	s,
		int	ch,
		const short *	samples,
		int	incr
	)			[static]

Definition at line 318 of file mpegaudioenc.c.

Referenced by av_resample(), avfilter_graph_dump_to_buf(), avfilter_graph_parse2(), avfilter_graph_queue_command(), avfilter_graph_send_command(), configure_input_audio_filter(), configure_input_video_filter(), configure_output_video_filter(), end_frame(), initFilter(), libAVEnumPins_Cleanup(), libAVEnumPins_Clone(), libAVPin_Disconnect(), libAVPin_QueryPinInfo(), libAVPin_ReceiveConnection(), main(), make_filters_from_proto(), MPA_encode_frame(), mpegts_open_pes_filter(), mpegts_open_section_filter(), pick_formats(), ps_hybrid_analysis_c(), put_image(), query_formats(), resample_one(), return_frame(), set_filter(), show_filters(), swri_resample_TMPL(), truespeech_apply_twopoint_filter(), tta_decode_frame(), xa_decode(), and yuv2yuvX_TMPL().

static void idct32	(	int *	out,
		int *	tab
	)			[static]

Definition at line 197 of file mpegaudioenc.c.

Referenced by filter().

static av_cold int MPA_encode_close

(

AVCodecContext *

avctx

)

[static]

Definition at line 772 of file mpegaudioenc.c.

static int MPA_encode_frame	(	AVCodecContext *	avctx,
		AVPacket *	avpkt,
		const AVFrame *	frame,
		int *	got_packet_ptr
	)			[static]

Definition at line 735 of file mpegaudioenc.c.

static av_cold int MPA_encode_init

(

AVCodecContext *

avctx

)

[static]

Definition at line 70 of file mpegaudioenc.c.

static void psycho_acoustic_model	(	MpegAudioContext *	s,
		short	smr[SBLIMIT]
	)			[static]

Definition at line 486 of file mpegaudioenc.c.

Referenced by MPA_encode_frame().

---

Variable Documentation

AVCodec ff_mp2_encoder

Initial value:

 {
    .name                  = "mp2",
    .type                  = AVMEDIA_TYPE_AUDIO,
    .id                    = AV_CODEC_ID_MP2,
    .priv_data_size        = sizeof(MpegAudioContext),
    .init                  = MPA_encode_init,
    .encode2               = MPA_encode_frame,
    .close                 = MPA_encode_close,
    .sample_fmts           = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,
                                                            AV_SAMPLE_FMT_NONE },
    .supported_samplerates = (const int[]){
        44100, 48000,  32000, 22050, 24000, 16000, 0
    },
    .channel_layouts       = (const uint64_t[]){ AV_CH_LAYOUT_MONO,
                                                 AV_CH_LAYOUT_STEREO,
                                                 0 },
    .long_name             = NULL_IF_CONFIG_SMALL("MP2 (MPEG audio layer 2)"),
    .defaults              = mp2_defaults,
}

Definition at line 785 of file mpegaudioenc.c.

const AVCodecDefault mp2_defaults[] [static]

Initial value:

 {
    { "b",    "128k" },
    { NULL },
}

Definition at line 780 of file mpegaudioenc.c.