bit.h File Reference

Definition of the mad_bit_ptr structure and methods, used in various low-level routines. More...

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Data Structures
struct	mad_bitptr
Defines
#define	mad_bit_finish(bitptr)
	nothing
#define	mad_bit_bitsleft(bitptr)   ((bitptr)->left)
Functions
void	mad_bit_init (struct mad_bitptr *, unsigned char const *)
	Initializes bit pointer struct.
unsigned int	mad_bit_length (struct mad_bitptr const *, struct mad_bitptr const *)
	Returns number of bits between start and end points.
unsigned char const *	mad_bit_nextbyte (struct mad_bitptr const *)
	Returns pointer to next unprocessed byte.
void	mad_bit_skip (struct mad_bitptr *, unsigned int)
	Advances bit pointer.
unsigned long	mad_bit_read (struct mad_bitptr *, unsigned int)
	Reads an arbitrary number of bits and return their UIMSBF value.
void	mad_bit_write (struct mad_bitptr *, unsigned int, unsigned long)
unsigned short	mad_bit_crc (struct mad_bitptr, unsigned int, unsigned short)
	Computes CRC-check word.

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Detailed Description

Definition of the mad_bit_ptr structure and methods, used in various low-level routines.

Definition in file bit.h.

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Define Documentation

#define mad_bit_bitsleft

(

bitptr

)

((bitptr)->left)

Definition at line 42 of file bit.h.

Referenced by III_huffdecode().

#define mad_bit_finish

(

bitptr

)

nothing

Definition at line 37 of file bit.h.

Referenced by mad_frame_decode(), mad_layer_III(), and mad_stream_finish().

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Function Documentation

unsigned short mad_bit_crc	(	struct	mad_bitptr,
		unsigned	int,
		unsigned	short
	)

Computes CRC-check word.

Definition at line 194 of file bit.c.

References CRC_POLY, crc_table, and mad_bit_read().

Referenced by decode_header(), mad_layer_I(), mad_layer_II(), and mad_layer_III().

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void mad_bit_init	(	struct mad_bitptr *	,
		unsigned char const *
	)

Initializes bit pointer struct.

Definition at line 91 of file bit.c.

References mad_bitptr::byte, mad_bitptr::cache, CHAR_BIT, and mad_bitptr::left.

Referenced by mad_frame_decode(), mad_header_decode(), mad_layer_III(), mad_stream_buffer(), mad_stream_init(), and mad_stream_sync().

unsigned int mad_bit_length	(	struct mad_bitptr const *	,
		struct mad_bitptr const *
	)

Returns number of bits between start and end points.

Definition at line 101 of file bit.c.

References mad_bitptr::byte, CHAR_BIT, and mad_bitptr::left.

Referenced by III_scalefactors(), III_scalefactors_lsf(), mad_frame_decode(), and mad_layer_II().

unsigned char const* mad_bit_nextbyte

(

struct mad_bitptr const *

)

Returns pointer to next unprocessed byte.

Definition at line 111 of file bit.c.

References mad_bitptr::byte, CHAR_BIT, and mad_bitptr::left.

Referenced by free_bitrate(), mad_header_decode(), mad_layer_III(), and mad_stream_sync().

unsigned long mad_bit_read	(	struct mad_bitptr *	,
		unsigned	int
	)

Reads an arbitrary number of bits and return their UIMSBF value.

Definition at line 136 of file bit.c.

References mad_bitptr::byte, mad_bitptr::cache, CHAR_BIT, and mad_bitptr::left.

Referenced by decode_header(), I_sample(), II_samples(), III_huffdecode(), III_scalefactors(), III_scalefactors_lsf(), III_sideinfo(), mad_bit_crc(), mad_layer_I(), mad_layer_II(), and mad_layer_III().

void mad_bit_skip	(	struct mad_bitptr *	,
		unsigned	int
	)

Advances bit pointer.

Definition at line 119 of file bit.c.

References mad_bitptr::byte, mad_bitptr::cache, CHAR_BIT, and mad_bitptr::left.

Referenced by decode_header(), free_bitrate(), III_huffdecode(), and mad_layer_III().

void mad_bit_write	(	struct mad_bitptr *	,
		unsigned	int,
		unsigned	long
	)