libavutil/lzo.c File Reference

#include "avutil.h"
#include "common.h"
#include <string.h>
#include "lzo.h"

Go to the source code of this file.

Data Structures
struct	LZOContext
Defines
#define	OUTBUF_PADDED   1
	Avoid e.g. MPlayers fast_memcpy, it slows things down here.
#define	INBUF_PADDED   1
	Define if we may read up to 8 bytes beyond the input buffer.
#define	GETB(c)   (*(c).in++)
#define	BUILTIN_MEMCPY
#define	COPY2(d, s)   memcpy(d, s, 2);
#define	COPY4(d, s)   memcpy(d, s, 4);
Functions
static int	get_byte (LZOContext *c)
	Reads one byte from the input buffer, avoiding an overrun.
static int	get_len (LZOContext *c, int x, int mask)
	Decodes a length value in the coding used by lzo.
static void	copy (LZOContext *c, int cnt)
	Copies bytes from input to output buffer with checking.
static void	memcpy_backptr (uint8_t *dst, int back, int cnt)
static void	copy_backptr (LZOContext *c, int back, int cnt)
	Copies previously decoded bytes to current position.
void	av_memcpy_backptr (uint8_t *dst, int back, int cnt)
	deliberately overlapping memcpy implementation
int	av_lzo1x_decode (void *out, int *outlen, const void *in, int *inlen)
	Decodes LZO 1x compressed data.

---

Define Documentation

#define BUILTIN_MEMCPY

Definition at line 72 of file lzo.c.

#define COPY2	(	d,
		s		)	memcpy(d, s, 2);

Definition at line 77 of file lzo.c.

Referenced by memcpy_backptr().

#define COPY4	(	d,
		s		)	memcpy(d, s, 4);

Definition at line 78 of file lzo.c.

Referenced by copy().

#define GETB

(

c

)

(*(c).in++)

Definition at line 51 of file lzo.c.

Referenced by av_lzo1x_decode().

#define INBUF_PADDED   1

Define if we may read up to 8 bytes beyond the input buffer.

Definition at line 32 of file lzo.c.

#define OUTBUF_PADDED   1

Avoid e.g. MPlayers fast_memcpy, it slows things down here.

Define if we may write up to 12 bytes beyond the output buffer.

Definition at line 30 of file lzo.c.

---

Function Documentation

static void copy	(	LZOContext *	c,
		int	cnt
	)			[inline, static]

Copies bytes from input to output buffer with checking.

Parameters:

cnt

number of bytes to copy, must be >= 0

Definition at line 88 of file lzo.c.

Referenced by av_lzo1x_decode(), avfilter_register_all(), frame_thread_init(), intra_predict(), qpeg_decode_intra(), resample(), roq_decode_frame(), rtmp_write(), and swr_convert().

static void copy_backptr	(	LZOContext *	c,
		int	back,
		int	cnt
	)			[inline, static]

Copies previously decoded bytes to current position.

Parameters:

	back	how many bytes back we start, must be > 0
	cnt	number of bytes to copy, must be >= 0

cnt > back is valid, this will copy the bytes we just copied, thus creating a repeating pattern with a period length of back.

Definition at line 121 of file lzo.c.

Referenced by av_lzo1x_decode().

static int get_byte

(

LZOContext *

c

)

[inline, static]

Reads one byte from the input buffer, avoiding an overrun.

Returns:

byte read

Definition at line 43 of file lzo.c.

static int get_len	(	LZOContext *	c,
		int	x,
		int	mask
	)			[inline, static]

Decodes a length value in the coding used by lzo.

Parameters:

	x	previous byte value
	mask	bits used from x

Returns:

decoded length value

Definition at line 62 of file lzo.c.

Referenced by av_lzo1x_decode().

static void memcpy_backptr	(	uint8_t *	dst,
		int	back,
		int	cnt
	)			[inline, static]

Definition at line 136 of file lzo.c.

Referenced by av_memcpy_backptr(), and copy_backptr().