libavcodec/lagarith.c File Reference

Lagarith lossless decoder. More...

#include "avcodec.h"
#include "get_bits.h"
#include "mathops.h"
#include "dsputil.h"
#include "lagarithrac.h"

Go to the source code of this file.

Data Structures

struct LagarithContext

Enumerations

enum LagarithFrameType {
  FRAME_RAW = 1, FRAME_U_RGB24 = 2, FRAME_ARITH_YUY2 = 3, FRAME_ARITH_RGB24 = 4,
  FRAME_SOLID_GRAY = 5, FRAME_SOLID_COLOR = 6, FRAME_OLD_ARITH_RGB = 7, FRAME_ARITH_RGBA = 8,
  FRAME_SOLID_RGBA = 9, FRAME_ARITH_YV12 = 10, FRAME_REDUCED_RES = 11
}

Functions

static uint64_t softfloat_reciprocal (uint32_t denom)

Compute the 52bit mantissa of 1/(double)denom.

static uint32_t softfloat_mul (uint32_t x, uint64_t mantissa)

(uint32_t)(x*f), where f has the given mantissa, and exponent 0 Used in combination with softfloat_reciprocal computes x/(double)denom.

static uint8_t lag_calc_zero_run (int8_t x)

static int lag_decode_prob (GetBitContext *gb, uint32_t *value)

static int lag_read_prob_header (lag_rac *rac, GetBitContext *gb)

static void add_lag_median_prediction (uint8_t *dst, uint8_t *src1, uint8_t *diff, int w, int *left, int *left_top)

static void lag_pred_line (LagarithContext *l, uint8_t *buf, int width, int stride, int line)

static int lag_decode_line (LagarithContext *l, lag_rac *rac, uint8_t *dst, int width, int stride, int esc_count)

static int lag_decode_zero_run_line (LagarithContext *l, uint8_t *dst, const uint8_t *src, int width, int esc_count)

static int lag_decode_arith_plane (LagarithContext *l, uint8_t *dst, int width, int height, int stride, const uint8_t *src, int src_size)

static int lag_decode_frame (AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)

Decode a frame.

static av_cold int lag_decode_init (AVCodecContext *avctx)

static av_cold int lag_decode_end (AVCodecContext *avctx)

Variables

AVCodec ff_lagarith_decoder

Detailed Description

Lagarith lossless decoder.

Author:: Nathan Caldwell

Definition in file lagarith.c.

Enumeration Type Documentation

enum LagarithFrameType

Enumerator:

FRAME_RAW	uncompressed
FRAME_U_RGB24	unaligned RGB24
FRAME_ARITH_YUY2	arithmetic coded YUY2
FRAME_ARITH_RGB24	arithmetic coded RGB24
FRAME_SOLID_GRAY	solid grayscale color frame
FRAME_SOLID_COLOR	solid non-grayscale color frame
FRAME_OLD_ARITH_RGB	obsolete arithmetic coded RGB (no longer encoded by upstream since version 1.1.0)
FRAME_ARITH_RGBA	arithmetic coded RGBA
FRAME_SOLID_RGBA	solid RGBA color frame
FRAME_ARITH_YV12	arithmetic coded YV12
FRAME_REDUCED_RES	reduced resolution YV12 frame

Definition at line 34 of file lagarith.c.

Function Documentation

static void add_lag_median_prediction	(	uint8_t *	dst,
		uint8_t *	src1,
		uint8_t *	diff,
		int	w,
		int *	left,
		int *	left_top
	)			`[static]`

Definition at line 221 of file lagarith.c.

Referenced by lag_pred_line().

static uint8_t lag_calc_zero_run ( int8_t x ) [static]

Definition at line 96 of file lagarith.c.

Referenced by lag_decode_line(), and lag_decode_zero_run_line().

static int lag_decode_arith_plane	(	LagarithContext *	l,
		uint8_t *	dst,
		int	width,
		int	height,
		int	stride,
		const uint8_t *	src,
		int	src_size
	)			`[static]`

Definition at line 358 of file lagarith.c.

Referenced by lag_decode_frame().

static av_cold int lag_decode_end ( AVCodecContext * avctx ) [static]

Definition at line 611 of file lagarith.c.

static int lag_decode_frame	(	AVCodecContext *	avctx,
		void *	data,
		int *	data_size,
		AVPacket *	avpkt
	)			`[static]`

Decode a frame.

Parameters:

	avctx	codec context
	data	output AVFrame
	data_size	size of output data or 0 if no picture is returned
	avpkt	input packet

Returns:: number of consumed bytes on success or negative if decode fails

Definition at line 439 of file lagarith.c.

static av_cold int lag_decode_init ( AVCodecContext * avctx ) [static]

Definition at line 601 of file lagarith.c.

static int lag_decode_line	(	LagarithContext *	l,
		lag_rac *	rac,
		uint8_t *	dst,
		int	width,
		int	stride,
		int	esc_count
	)			`[static]`

Definition at line 270 of file lagarith.c.

Referenced by lag_decode_arith_plane().

static int lag_decode_prob	(	GetBitContext *	gb,
		uint32_t *	value
	)			`[static]`

Definition at line 101 of file lagarith.c.

Referenced by lag_read_prob_header().

static int lag_decode_zero_run_line	(	LagarithContext *	l,
		uint8_t *	dst,
		const uint8_t *	src,
		int	width,
		int	esc_count
	)			`[static]`

Definition at line 312 of file lagarith.c.

Referenced by lag_decode_arith_plane().

static void lag_pred_line	(	LagarithContext *	l,
		uint8_t *	buf,
		int	width,
		int	stride,
		int	line
	)			`[static]`

Definition at line 245 of file lagarith.c.

Referenced by lag_decode_arith_plane().

static int lag_read_prob_header	(	lag_rac *	rac,
		GetBitContext *	gb
	)			`[static]`

Definition at line 135 of file lagarith.c.

Referenced by lag_decode_arith_plane().

static uint32_t softfloat_mul	(	uint32_t	x,
		uint64_t	mantissa
	)			`[static]`

(uint32_t)(x*f), where f has the given mantissa, and exponent 0 Used in combination with softfloat_reciprocal computes x/(double)denom.

Parameters:

	x	32bit integer factor
	mantissa	mantissa of f with exponent 0

Returns:: 32bit integer value (x*f)

See also:: softfloat_reciprocal

Definition at line 85 of file lagarith.c.

Referenced by lag_read_prob_header().

static uint64_t softfloat_reciprocal ( uint32_t denom ) [static]

Compute the 52bit mantissa of 1/(double)denom.

This crazy format uses floats in an entropy coder and we have to match x86 rounding exactly, thus ordinary floats aren't portable enough.

Parameters:

denom

denominator

Returns:: 52bit mantissa

See also:: softfloat_mul

Definition at line 66 of file lagarith.c.

Referenced by lag_read_prob_header().

Variable Documentation

AVCodec ff_lagarith_decoder

Initial value:

 {
    .name           = "lagarith",
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = CODEC_ID_LAGARITH,
    .priv_data_size = sizeof(LagarithContext),
    .init           = lag_decode_init,
    .close          = lag_decode_end,
    .decode         = lag_decode_frame,
    .capabilities   = CODEC_CAP_DR1,
    .long_name = NULL_IF_CONFIG_SMALL("Lagarith lossless"),
}

Definition at line 622 of file lagarith.c.


Data Structures
struct	LagarithContext
Enumerations
enum	LagarithFrameType { FRAME_RAW = 1, FRAME_U_RGB24 = 2, FRAME_ARITH_YUY2 = 3, FRAME_ARITH_RGB24 = 4, FRAME_SOLID_GRAY = 5, FRAME_SOLID_COLOR = 6, FRAME_OLD_ARITH_RGB = 7, FRAME_ARITH_RGBA = 8, FRAME_SOLID_RGBA = 9, FRAME_ARITH_YV12 = 10, FRAME_REDUCED_RES = 11 }
Functions
static uint64_t	softfloat_reciprocal (uint32_t denom)
	Compute the 52bit mantissa of 1/(double)denom.
static uint32_t	softfloat_mul (uint32_t x, uint64_t mantissa)
	(uint32_t)(x*f), where f has the given mantissa, and exponent 0 Used in combination with softfloat_reciprocal computes x/(double)denom.
static uint8_t	lag_calc_zero_run (int8_t x)
static int	lag_decode_prob (GetBitContext gb, uint32_t value)
static int	lag_read_prob_header (lag_rac rac, GetBitContext gb)
static void	add_lag_median_prediction (uint8_t dst, uint8_t src1, uint8_t diff, int w, int left, int *left_top)
static void	lag_pred_line (LagarithContext l, uint8_t buf, int width, int stride, int line)
static int	lag_decode_line (LagarithContext l, lag_rac rac, uint8_t *dst, int width, int stride, int esc_count)
static int	lag_decode_zero_run_line (LagarithContext l, uint8_t dst, const uint8_t *src, int width, int esc_count)
static int	lag_decode_arith_plane (LagarithContext l, uint8_t dst, int width, int height, int stride, const uint8_t *src, int src_size)
static int	lag_decode_frame (AVCodecContext avctx, void data, int data_size, AVPacket avpkt)
	Decode a frame.
static av_cold int	lag_decode_init (AVCodecContext *avctx)
static av_cold int	lag_decode_end (AVCodecContext *avctx)
Variables
AVCodec	ff_lagarith_decoder