flacdec.c File Reference

FLAC (Free Lossless Audio Codec) decoder. More...

#include <limits.h>
#include "libavutil/avassert.h"
#include "libavutil/crc.h"
#include "libavutil/opt.h"
#include "avcodec.h"
#include "internal.h"
#include "get_bits.h"
#include "bytestream.h"
#include "golomb.h"
#include "flac.h"
#include "flacdata.h"
#include "flacdsp.h"
#include "thread.h"
#include "unary.h"

Go to the source code of this file.

Data Structures
struct	FLACContext

Functions
static int	allocate_buffers (FLACContext *s)
static void	flac_set_bps (FLACContext *s)
static av_cold int	flac_decode_init (AVCodecContext *avctx)
static void	dump_headers (AVCodecContext *avctx, FLACStreaminfo *s)
static int	parse_streaminfo (FLACContext *s, const uint8_t *buf, int buf_size)
	Parse the STREAMINFO from an inline header. More...
static int	get_metadata_size (const uint8_t *buf, int buf_size)
	Determine the size of an inline header. More...
static int	decode_residuals (FLACContext *s, int32_t *decoded, int pred_order)
static int	decode_subframe_fixed (FLACContext *s, int32_t *decoded, int pred_order, int bps)
static void	lpc_analyze_remodulate (SUINT32 *decoded, const int coeffs[32], int order, int qlevel, int len, int bps)
static int	decode_subframe_lpc (FLACContext *s, int32_t *decoded, int pred_order, int bps)
static int	decode_subframe (FLACContext *s, int channel)
static int	decode_frame (FLACContext *s)
static int	flac_decode_frame (AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
static av_cold int	flac_decode_close (AVCodecContext *avctx)

Variables
static const AVOption	options []
static const AVClass	flac_decoder_class
AVCodec	ff_flac_decoder

Detailed Description

FLAC (Free Lossless Audio Codec) decoder.

Author

Alex Beregszaszi

See also

http://flac.sourceforge.net/

This decoder can be used in 1 of 2 ways: Either raw FLAC data can be fed through, starting from the initial 'fLaC' signature; or by passing the 34-byte streaminfo structure through avctx->extradata[_size] followed by data starting with the 0xFFF8 marker.

Definition in file flacdec.c.

Function Documentation

allocate_buffers()

static int allocate_buffers ( FLACContext *  s )

static

Definition at line 135 of file flacdec.c.

Referenced by decode_frame(), flac_decode_frame(), flac_decode_init(), and parse_streaminfo().

flac_set_bps()

static void flac_set_bps ( FLACContext *  s )

static

Definition at line 73 of file flacdec.c.

Referenced by decode_frame(), flac_decode_init(), and parse_streaminfo().

flac_decode_init()

static av_cold int flac_decode_init ( AVCodecContext *  avctx )

static

Definition at line 95 of file flacdec.c.

dump_headers()

static void dump_headers ( AVCodecContext *  avctx, FLACStreaminfo *  s  )

static

Definition at line 126 of file flacdec.c.

Referenced by decode_frame().

parse_streaminfo()

static int parse_streaminfo ( FLACContext *  s, const uint8_t *  buf, int  buf_size  )

static

Parse the STREAMINFO from an inline header.

Parameters

s	the flac decoding context
buf	input buffer, starting with the "fLaC" marker
buf_size	buffer size

Returns

non-zero if metadata is invalid

Definition at line 167 of file flacdec.c.

Referenced by flac_decode_frame().

get_metadata_size()

static int get_metadata_size ( const uint8_t *  buf, int  buf_size  )

static

Determine the size of an inline header.

Parameters

buf	input buffer, starting with the "fLaC" marker
buf_size	buffer size

Returns

number of bytes in the header, or 0 if more data is needed

Definition at line 200 of file flacdec.c.

Referenced by flac_decode_frame().

decode_residuals()

static int decode_residuals ( FLACContext *  s, int32_t *  decoded, int  pred_order  )

static

Definition at line 221 of file flacdec.c.

Referenced by decode_subframe_fixed(), and decode_subframe_lpc().

decode_subframe_fixed()

static int decode_subframe_fixed ( FLACContext *  s, int32_t *  decoded, int  pred_order, int  bps  )

static

Definition at line 282 of file flacdec.c.

Referenced by decode_subframe().

lpc_analyze_remodulate()

static void lpc_analyze_remodulate ( SUINT32 *  decoded, const int  coeffs[32], int  order, int  qlevel, int  len, int  bps  )

static

Definition at line 334 of file flacdec.c.

Referenced by decode_subframe_lpc().

decode_subframe_lpc()

static int decode_subframe_lpc ( FLACContext *  s, int32_t *  decoded, int  pred_order, int  bps  )

static

Definition at line 361 of file flacdec.c.

Referenced by decode_subframe().

decode_subframe()

static int decode_subframe ( FLACContext *  s, int  channel  )

inlinestatic

Definition at line 405 of file flacdec.c.

Referenced by decode_frame().

decode_frame()

static int decode_frame ( FLACContext *  s )

static

Definition at line 472 of file flacdec.c.

Referenced by flac_decode_frame().

flac_decode_frame()

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

static

Definition at line 558 of file flacdec.c.

flac_decode_close()

static av_cold int flac_decode_close ( AVCodecContext *  avctx )

static

Definition at line 655 of file flacdec.c.

Variable Documentation

options

const AVOption options[]

static

Initial value:

= {
{ "use_buggy_lpc", "emulate old buggy lavc behavior", 0x42, AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_AUDIO_PARAM },
{ NULL },
}

Definition at line 664 of file flacdec.c.

flac_decoder_class

const AVClass flac_decoder_class

static

Initial value:

= {
    "FLAC decoder",
    av_default_item_name,
    options,
    LIBAVUTIL_VERSION_INT,
}

Definition at line 669 of file flacdec.c.

ff_flac_decoder

AVCodec ff_flac_decoder

Initial value:

= {
    .name           = "flac",
    .long_name      = NULL_IF_CONFIG_SMALL("FLAC (Free Lossless Audio Codec)"),
    .type           = AVMEDIA_TYPE_AUDIO,
    .id             = AV_CODEC_ID_FLAC,
    .priv_data_size = sizeof(FLACContext),
    .init           = flac_decode_init,
    .close          = flac_decode_close,
    .decode         = flac_decode_frame,
    .init_thread_copy = ONLY_IF_THREADS_ENABLED(init_thread_copy),
    .capabilities   = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
    .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16,
                                                      AV_SAMPLE_FMT_S16P,
                                                      AV_SAMPLE_FMT_S32,
                                                      AV_SAMPLE_FMT_S32P,
                                                      AV_SAMPLE_FMT_NONE },
    .priv_class     = &flac_decoder_class,
}

Definition at line 676 of file flacdec.c.