lagarith.c File Reference

Lagarith lossless decoder. More...

#include <inttypes.h>
#include "avcodec.h"
#include "get_bits.h"
#include "mathops.h"
#include "lagarithrac.h"
#include "lossless_videodsp.h"
#include "thread.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 52-bit mantissa of 1/(double)denom. More...
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. More...
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 void	lag_pred_line_yuy2 (LagarithContext *l, uint8_t *buf, int width, int stride, int line, int is_luma)
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, const uint8_t *src_end, 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 *got_frame, AVPacket *avpkt)
	Decode a frame. More...
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

LagarithFrameType

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 37 of file lagarith.c.

Function Documentation

softfloat_reciprocal()

static uint64_t softfloat_reciprocal ( uint32_t  denom )

static

Compute the 52-bit 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

52-bit mantissa

See also

softfloat_mul

Definition at line 69 of file lagarith.c.

Referenced by lag_read_prob_header().

softfloat_mul()

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

Returns

32-bit integer value (x*f)

See also

softfloat_reciprocal

Definition at line 88 of file lagarith.c.

Referenced by lag_read_prob_header().

lag_calc_zero_run()

static uint8_t lag_calc_zero_run ( int8_t  x )

static

Definition at line 99 of file lagarith.c.

Referenced by lag_decode_line(), and lag_decode_zero_run_line().

lag_decode_prob()

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

static

Definition at line 104 of file lagarith.c.

Referenced by lag_read_prob_header().

lag_read_prob_header()

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

static

Definition at line 138 of file lagarith.c.

Referenced by lag_decode_arith_plane().

add_lag_median_prediction()

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 234 of file lagarith.c.

Referenced by lag_pred_line().

lag_pred_line()

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

static

Definition at line 258 of file lagarith.c.

Referenced by lag_decode_arith_plane().

lag_pred_line_yuy2()

static void lag_pred_line_yuy2 ( LagarithContext *  l, uint8_t *  buf, int  width, int  stride, int  line, int  is_luma  )

static

Definition at line 284 of file lagarith.c.

Referenced by lag_decode_arith_plane().

lag_decode_line()

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

static

Definition at line 321 of file lagarith.c.

Referenced by lag_decode_arith_plane().

lag_decode_zero_run_line()

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

static

Definition at line 363 of file lagarith.c.

Referenced by lag_decode_arith_plane().

lag_decode_arith_plane()

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 421 of file lagarith.c.

Referenced by lag_decode_frame().

lag_decode_frame()

static int lag_decode_frame ( AVCodecContext *  avctx, void *  data, int *  got_frame, 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 529 of file lagarith.c.

lag_decode_init()

static av_cold int lag_decode_init ( AVCodecContext *  avctx )

static

Definition at line 727 of file lagarith.c.

lag_decode_end()

static av_cold int lag_decode_end ( AVCodecContext *  avctx )

static

Definition at line 747 of file lagarith.c.

Variable Documentation

ff_lagarith_decoder

AVCodec ff_lagarith_decoder

Initial value:

= {
    .name           = "lagarith",
    .long_name      = NULL_IF_CONFIG_SMALL("Lagarith lossless"),
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = AV_CODEC_ID_LAGARITH,
    .priv_data_size = sizeof(LagarithContext),
    .init           = lag_decode_init,
    .init_thread_copy = ONLY_IF_THREADS_ENABLED(lag_decode_init_thread_copy),
    .close          = lag_decode_end,
    .decode         = lag_decode_frame,
    .capabilities   = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
}

Definition at line 756 of file lagarith.c.