#include "libavutil/attributes.h"
#include "libavutil/avassert.h"
#include "avcodec.h"
#include "internal.h"
#include "get_bits.h"
#include "put_bits.h"
#include "wma.h"
#include "wma_common.h"

Data Structures
struct	WmallChannelCtx
	frame-specific decoder context for a single channel More...

struct	WmallDecodeCtx
	main decoder context More...

Macros
#define	WMALL_MAX_CHANNELS 8
	current decoder limitations

#define	MAX_SUBFRAMES 32
	max number of subframes per channel

#define	MAX_BANDS 29
	max number of scale factor bands

#define	MAX_FRAMESIZE 32768
	maximum compressed frame size

#define	MAX_ORDER 256

#define	WMALL_BLOCK_MIN_BITS 6
	log2 of min block size

#define	WMALL_BLOCK_MAX_BITS 14
	log2 of max block size

#define	WMALL_BLOCK_MAX_SIZE (1 << WMALL_BLOCK_MAX_BITS)
	maximum block size

#define	WMALL_BLOCK_SIZES (WMALL_BLOCK_MAX_BITS - WMALL_BLOCK_MIN_BITS + 1)
	possible block sizes

Functions
static av_cold int	decode_init (AVCodecContext *avctx)

static int	decode_subframe_length (WmallDecodeCtx *s, int offset)
	Decode the subframe length.

static int	decode_tilehdr (WmallDecodeCtx *s)
	Decode how the data in the frame is split into subframes.

static void	decode_ac_filter (WmallDecodeCtx *s)

static void	decode_mclms (WmallDecodeCtx *s)

static int	decode_cdlms (WmallDecodeCtx *s)

static int	decode_channel_residues (WmallDecodeCtx *s, int ch, int tile_size)

static void	decode_lpc (WmallDecodeCtx *s)

static void	clear_codec_buffers (WmallDecodeCtx *s)

static void	reset_codec (WmallDecodeCtx *s)
	Reset filter parameters and transient area at new seekable tile.

static void	mclms_update (WmallDecodeCtx s, int icoef, int pred)

static void	mclms_predict (WmallDecodeCtx s, int icoef, int pred)

static void	revert_mclms (WmallDecodeCtx *s, int tile_size)

static int	lms_predict (WmallDecodeCtx *s, int ich, int ilms)

static void	lms_update (WmallDecodeCtx *s, int ich, int ilms, int input, int residue)

static void	use_high_update_speed (WmallDecodeCtx *s, int ich)

static void	use_normal_update_speed (WmallDecodeCtx *s, int ich)

static void	revert_cdlms (WmallDecodeCtx *s, int ch, int coef_begin, int coef_end)

static void	revert_inter_ch_decorr (WmallDecodeCtx *s, int tile_size)

static void	revert_acfilter (WmallDecodeCtx *s, int tile_size)

static int	decode_subframe (WmallDecodeCtx *s)

static int	decode_frame (WmallDecodeCtx *s)
	Decode one WMA frame.

static int	remaining_bits (WmallDecodeCtx s, GetBitContext gb)
	Calculate remaining input buffer length.

static void	save_bits (WmallDecodeCtx s, GetBitContext gb, int len, int append)
	Fill the bit reservoir with a (partial) frame.

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

static void	flush (AVCodecContext *avctx)

static av_cold int	decode_close (AVCodecContext *avctx)

Variables
AVCodec	ff_wmalossless_decoder

Macro Definition Documentation

#define WMALL_MAX_CHANNELS 8

current decoder limitations

max number of handled channels

Definition at line 36 of file wmalosslessdec.c.

Referenced by decode_init(), decode_tilehdr(), and revert_mclms().

#define MAX_SUBFRAMES 32

max number of subframes per channel

Definition at line 37 of file wmalosslessdec.c.

Referenced by decode_init(), and decode_tilehdr().

#define MAX_BANDS 29

max number of scale factor bands

Definition at line 38 of file wmalosslessdec.c.

#define MAX_FRAMESIZE 32768

maximum compressed frame size

Definition at line 39 of file wmalosslessdec.c.

Referenced by decode_init(), decode_packet(), flush(), and save_bits().

#define MAX_ORDER 256

Definition at line 40 of file wmalosslessdec.c.

Referenced by decode_cdlms().

#define WMALL_BLOCK_MIN_BITS 6

log2 of min block size

Definition at line 42 of file wmalosslessdec.c.

#define WMALL_BLOCK_MAX_BITS 14

log2 of max block size

Definition at line 43 of file wmalosslessdec.c.

#define WMALL_BLOCK_MAX_SIZE (1 << WMALL_BLOCK_MAX_BITS)

maximum block size

Definition at line 44 of file wmalosslessdec.c.

Referenced by decode_init().

#define WMALL_BLOCK_SIZES (WMALL_BLOCK_MAX_BITS - WMALL_BLOCK_MIN_BITS + 1)

possible block sizes

Definition at line 45 of file wmalosslessdec.c.

Function Documentation

static av_cold int decode_init ( AVCodecContext * avctx )

static

Definition at line 174 of file wmalosslessdec.c.

static int decode_subframe_length	(	WmallDecodeCtx *	s,
		int	offset
	)

static

Decode the subframe length.

Parameters

s	context
offset	sample offset in the frame

Returns: decoded subframe length on success, < 0 in case of an error

Definition at line 283 of file wmalosslessdec.c.

Referenced by decode_tilehdr().

static int decode_tilehdr ( WmallDecodeCtx * s )

static

Decode how the data in the frame is split into subframes.

  Every WMA frame contains the encoded data for a fixed number of
  samples per channel. The data for every channel might be split
  into several subframes. This function will reconstruct the list of
  subframes for every channel.

  If the subframes are not evenly split, the algorithm estimates the
  channels with the lowest number of total samples.
  Afterwards, for each of these channels a bit is read from the
  bitstream that indicates if the channel contains a subframe with the
  next subframe size that is going to be read from the bitstream or not.
  If a channel contains such a subframe, the subframe size gets added to
  the channel's subframe list.
  The algorithm repeats these steps until the frame is properly divided
  between the individual channels.

Parameters

s context

Returns: 0 on success, < 0 in case of an error

Definition at line 325 of file wmalosslessdec.c.

Referenced by decode_frame().

static void decode_ac_filter ( WmallDecodeCtx * s )

static

Definition at line 410 of file wmalosslessdec.c.

Referenced by decode_subframe().

static void decode_mclms ( WmallDecodeCtx * s )

static

Definition at line 421 of file wmalosslessdec.c.

Referenced by decode_subframe().

static int decode_cdlms ( WmallDecodeCtx * s )

static

Definition at line 444 of file wmalosslessdec.c.

Referenced by decode_subframe().

static int decode_channel_residues	(	WmallDecodeCtx *	s,
		int	ch,
		int	tile_size
	)

static

Definition at line 490 of file wmalosslessdec.c.

Referenced by decode_subframe().

static void decode_lpc ( WmallDecodeCtx * s )

static

Definition at line 549 of file wmalosslessdec.c.

Referenced by decode_subframe().

static void clear_codec_buffers ( WmallDecodeCtx * s )

static

Definition at line 561 of file wmalosslessdec.c.

Referenced by decode_subframe().

static void reset_codec ( WmallDecodeCtx * s )

static

Reset filter parameters and transient area at new seekable tile.

Definition at line 590 of file wmalosslessdec.c.

Referenced by decode_subframe().

static void mclms_update	(	WmallDecodeCtx *	s,
		int	icoef,
		int *	pred
	)

static

Definition at line 605 of file wmalosslessdec.c.

Referenced by revert_mclms().

static void mclms_predict	(	WmallDecodeCtx *	s,
		int	icoef,
		int *	pred
	)

static

Definition at line 663 of file wmalosslessdec.c.

Referenced by revert_mclms().

static void revert_mclms	(	WmallDecodeCtx *	s,
		int	tile_size
	)

static

Definition at line 685 of file wmalosslessdec.c.

Referenced by decode_subframe().

static int lms_predict	(	WmallDecodeCtx *	s,
		int	ich,
		int	ilms
	)

static

Definition at line 694 of file wmalosslessdec.c.

Referenced by revert_cdlms().

static void lms_update	(	WmallDecodeCtx *	s,
		int	ich,
		int	ilms,
		int	input,
		int	residue
	)

static

Definition at line 706 of file wmalosslessdec.c.

Referenced by revert_cdlms().

static void use_high_update_speed	(	WmallDecodeCtx *	s,
		int	ich
	)

static

Definition at line 748 of file wmalosslessdec.c.

Referenced by decode_subframe().

static void use_normal_update_speed	(	WmallDecodeCtx *	s,
		int	ich
	)

static

Definition at line 766 of file wmalosslessdec.c.

Referenced by decode_subframe().

static void revert_cdlms	(	WmallDecodeCtx *	s,
		int	ch,
		int	coef_begin,
		int	coef_end
	)

static

Definition at line 783 of file wmalosslessdec.c.

Referenced by decode_subframe().

static void revert_inter_ch_decorr	(	WmallDecodeCtx *	s,
		int	tile_size
	)

static

Definition at line 801 of file wmalosslessdec.c.

Referenced by decode_subframe().

static void revert_acfilter	(	WmallDecodeCtx *	s,
		int	tile_size
	)

static

Definition at line 814 of file wmalosslessdec.c.

Referenced by decode_subframe().

static int decode_subframe ( WmallDecodeCtx * s )

static

Definition at line 846 of file wmalosslessdec.c.

Referenced by decode_frame().

static int decode_frame ( WmallDecodeCtx * s )

static

Decode one WMA frame.

Parameters

s	codec context

Returns: 0 if the trailer bit indicates that this is the last frame, 1 if there are additional frames

Definition at line 1020 of file wmalosslessdec.c.

Referenced by decode_packet().

static int remaining_bits	(	WmallDecodeCtx *	s,
		GetBitContext *	gb
	)

static

Calculate remaining input buffer length.

Parameters

s	codec context
gb	bitstream reader context

Returns: remaining size in bits

Definition at line 1119 of file wmalosslessdec.c.

Referenced by decode_packet().

static void save_bits	(	WmallDecodeCtx *	s,
		GetBitContext *	gb,
		int	len,
		int	append
	)

static

Fill the bit reservoir with a (partial) frame.

Parameters

s	codec context
gb	bitstream reader context
len	length of the partial frame
append	decides whether to reset the buffer or not

Definition at line 1131 of file wmalosslessdec.c.

Referenced by decode_packet().

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

static

Definition at line 1175 of file wmalosslessdec.c.

static void flush ( AVCodecContext * avctx )

static

Definition at line 1289 of file wmalosslessdec.c.

static av_cold int decode_close ( AVCodecContext * avctx )

static

Definition at line 1302 of file wmalosslessdec.c.

Variable Documentation

AVCodec ff_wmalossless_decoder

Initial value:

= {
    .name           = "wmalossless",
    .long_name      = NULL_IF_CONFIG_SMALL("Windows Media Audio Lossless"),
    .type           = AVMEDIA_TYPE_AUDIO,
    .id             = AV_CODEC_ID_WMALOSSLESS,
    .priv_data_size = sizeof(WmallDecodeCtx),
    .init           = decode_init,
    .close          = decode_close,
    .decode         = decode_packet,
    .flush          = flush,
    .capabilities   = CODEC_CAP_SUBFRAMES | CODEC_CAP_DR1 | CODEC_CAP_DELAY,
    .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
                                                      AV_SAMPLE_FMT_S32P,
                                                      AV_SAMPLE_FMT_NONE },
}

Definition at line 1311 of file wmalosslessdec.c.

Data Structures

Macros

Functions

Variables

Macro Definition Documentation

Function Documentation

Variable Documentation