intrax8.c File Reference

IntraX8 (J-Frame) subdecoder, used by WMV2 and VC-1. More...

#include "libavutil/avassert.h"
#include "avcodec.h"
#include "get_bits.h"
#include "idctdsp.h"
#include "msmpeg4data.h"
#include "intrax8huf.h"
#include "intrax8.h"
#include "intrax8dsp.h"
#include "mpegutils.h"

Macros
#define	MAX_TABLE_DEPTH(table_bits, max_bits)   ((max_bits + table_bits - 1) / table_bits)
#define	DC_VLC_BITS   9
#define	AC_VLC_BITS   9
#define	OR_VLC_BITS   7
#define	DC_VLC_MTD   MAX_TABLE_DEPTH(DC_VLC_BITS, MAX_DC_VLC_BITS)
#define	AC_VLC_MTD   MAX_TABLE_DEPTH(AC_VLC_BITS, MAX_AC_VLC_BITS)
#define	OR_VLC_MTD   MAX_TABLE_DEPTH(OR_VLC_BITS, MAX_OR_VLC_BITS)
#define	init_ac_vlc(dst, src)
#define	init_dc_vlc(dst, src)
#define	init_or_vlc(dst, src)
#define	extra_bits(eb)   (eb)
#define	extra_run   (0xFF << 8)
#define	extra_level   (0x00 << 8)
#define	run_offset(r)   ((r) << 16)
#define	level_offset(l)   ((l) << 24)
#define	B(x, y)   w->block[0][w->idct_permutation[(x) + (y) * 8]]
#define	T(x)   ((x) * dc_level + 0x8000) >> 16;

Functions
av_cold int	ff_intrax8_common_init (AVCodecContext *avctx, IntraX8Context *w, IDCTDSPContext *idsp, int16_t(*block)[64], int block_last_index[12], int mb_width, int mb_height)
	Initialize IntraX8 frame decoder. More...
av_cold void	ff_intrax8_common_end (IntraX8Context *w)
	Destroy IntraX8 frame structure. More...
int	ff_intrax8_decode_picture (IntraX8Context *w, Picture *pict, GetBitContext *gb, int *mb_x, int *mb_y, int dquant, int quant_offset, int loopfilter, int lowdelay)
	Decode single IntraX8 frame. More...

Detailed Description

IntraX8 (J-Frame) subdecoder, used by WMV2 and VC-1.

Macro Definition Documentation

init_ac_vlc

#define init_ac_vlc	(		dst,
			src
	)

Value:

do {                                                                      \
        dst.table           = &table[offset];                                 \
        dst.table_allocated = sizes[sizeidx];                                 \
        offset             += sizes[sizeidx++];                               \
        init_vlc(&dst, AC_VLC_BITS, 77, &src[1], 4, 2, &src[0], 4, 2,         \
                 INIT_VLC_USE_NEW_STATIC);                                    \
    } while(0)

init_dc_vlc

#define init_dc_vlc	(		dst,
			src
	)

Value:

do {                                                                      \
        dst.table           = &table[offset];                                 \
        dst.table_allocated = sizes[sizeidx];                                 \
        offset             += sizes[sizeidx++];                               \
        init_vlc(&dst, DC_VLC_BITS, 34, &src[1], 4, 2, &src[0], 4, 2,         \
                 INIT_VLC_USE_NEW_STATIC);                                    \
    } while(0)

init_or_vlc

#define init_or_vlc	(		dst,
			src
	)

Value:

do {                                                                      \
        dst.table           = &table[offset];                                 \
        dst.table_allocated = sizes[sizeidx];                                 \
        offset             += sizes[sizeidx++];                               \
        init_vlc(&dst, OR_VLC_BITS, 12, &src[1], 4, 2, &src[0], 4, 2,         \
                 INIT_VLC_USE_NEW_STATIC);                                    \
    } while(0)

Function Documentation

ff_intrax8_common_end()

av_cold void ff_intrax8_common_end

(

IntraX8Context *

w

)

Destroy IntraX8 frame structure.

Parameters

w	pointer to IntraX8Context

ff_intrax8_common_init()

av_cold int ff_intrax8_common_init	(	AVCodecContext *	avctx,
		IntraX8Context *	w,
		IDCTDSPContext *	idsp,
		int16_t(*)	block[64],
		int	block_last_index[12],
		int	mb_width,
		int	mb_height
	)

Initialize IntraX8 frame decoder.

Parameters

avctx	pointer to AVCodecContext
w	pointer to IntraX8Context
idsp	pointer to IDCTDSPContext
block	pointer to block array
block_last_index	pointer to index array
mb_width	macroblock width
mb_height	macroblock height

Returns

0 on success, a negative AVERROR value on error

ff_intrax8_decode_picture()

int ff_intrax8_decode_picture	(	IntraX8Context *	w,
		Picture *	pict,
		GetBitContext *	gb,
		int *	mb_x,
		int *	mb_y,
		int	quant,
		int	halfpq,
		int	loopfilter,
		int	lowdelay
	)

Decode single IntraX8 frame.

lowres decoding is theoretically impossible.

Parameters

w	pointer to IntraX8Context
pict	the output Picture containing an AVFrame
gb	open bitstream reader
mb_x	pointer to the x coordinate of the current macroblock
mb_y	pointer to the y coordinate of the current macroblock
dquant	doubled quantizer, it would be odd in case of VC-1 halfpq==1.
quant_offset	offset away from zero
loopfilter	enable filter after decoding a block