alac.c File Reference

ALAC (Apple Lossless Audio Codec) decoder. More...

#include <inttypes.h>
#include "libavutil/channel_layout.h"
#include "libavutil/opt.h"
#include "avcodec.h"
#include "get_bits.h"
#include "bytestream.h"
#include "internal.h"
#include "thread.h"
#include "unary.h"
#include "mathops.h"
#include "alac_data.h"
#include "alacdsp.h"

Classes
struct	ALACContext

Macros
#define	ALAC_EXTRADATA_SIZE   36

Typedefs
typedef struct ALACContext	ALACContext

Variables
AVCodec	ff_alac_decoder

Detailed Description

ALAC (Apple Lossless Audio Codec) decoder.

Author

2005 David Hammerton

See also

http://crazney.net/programs/itunes/alac.html

Note: This decoder expects a 36-byte QuickTime atom to be passed through the extradata[_size] fields. This atom is tacked onto the end of an 'alac' stsd atom and has the following format:

32 bits atom size 32 bits tag ("alac") 32 bits tag version (0) 32 bits samples per frame (used when not set explicitly in the frames) 8 bits compatible version (0) 8 bits sample size 8 bits history mult (40) 8 bits initial history (10) 8 bits rice param limit (14) 8 bits channels 16 bits maxRun (255) 32 bits max coded frame size (0 means unknown) 32 bits average bitrate (0 means unknown) 32 bits samplerate

Variable Documentation

ff_alac_decoder

AVCodec ff_alac_decoder

Initial value:

= {
    .name           = "alac",
    .long_name      = NULL_IF_CONFIG_SMALL("ALAC (Apple Lossless Audio Codec)"),
    .type           = AVMEDIA_TYPE_AUDIO,
    .id             = AV_CODEC_ID_ALAC,
    .priv_data_size = sizeof(ALACContext),
    .init           = alac_decode_init,
    .close          = alac_decode_close,
    .decode         = alac_decode_frame,
    .init_thread_copy = ONLY_IF_THREADS_ENABLED(init_thread_copy),
    .capabilities   = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
    .priv_class     = &alac_class
}