diracdec.c File Reference

Dirac Decoder. More...

#include "libavutil/pixdesc.h"
#include "libavutil/thread.h"
#include "avcodec.h"
#include "get_bits.h"
#include "bytestream.h"
#include "internal.h"
#include "golomb.h"
#include "dirac_arith.h"
#include "dirac_vlc.h"
#include "mpeg12data.h"
#include "libavcodec/mpegvideo.h"
#include "mpegvideoencdsp.h"
#include "dirac_dwt.h"
#include "dirac.h"
#include "diractab.h"
#include "diracdsp.h"
#include "videodsp.h"

Classes
struct	DiracFrame
struct	DiracBlock
struct	SubBand
struct	Plane
struct	DiracSlice
struct	DiracContext
struct	SliceCoeffs

Macros
#define	MAX_REFERENCE_FRAMES   8
	The spec limits this to 3 for frame coding, but in practice can be as high as 6.
#define	MAX_DELAY   5 /* limit for main profile for frame coding (TODO: field coding) */
#define	MAX_FRAMES   (MAX_REFERENCE_FRAMES + MAX_DELAY + 1)
#define	MAX_QUANT   255 /* max quant for VC-2 */
#define	MAX_BLOCKSIZE   32 /* maximum xblen/yblen we support */
#define	DIRAC_REF_MASK_REF1   1
	DiracBlock->ref flags, if set then the block does MC from the given ref.
#define	DIRAC_REF_MASK_REF2   2
#define	DIRAC_REF_MASK_GLOBAL   4
#define	DELAYED_PIC_REF   4
	Value of Picture.reference when Picture is not a reference picture, but is held for delayed output.
#define	CALC_PADDING(size, depth)   (((size + (1 << depth) - 1) >> depth) << depth)
#define	DIVRNDUP(a, b)   (((a) + (b) - 1) / (b))
#define	SIGN_CTX(x)   (CTX_SIGN_ZERO + ((x) > 0) - ((x) < 0))
#define	UNPACK_ARITH(n, type)
#define	INTRA_DC_PRED(n, type)
	Dirac Specification -> 13.3 intra_dc_prediction(band) More...
#define	PARSE_VALUES(type, x, gb, ebits, buf1, buf2)
#define	CHECKEDREAD(dst, cond, errmsg)
#define	ROLLOFF(i)
#define	DATA_UNIT_HEADER_SIZE   13
	Dirac Specification -> 9.6 Parse Info Header Syntax. More...

Typedefs
typedef struct SubBand	SubBand
typedef struct Plane	Plane
typedef struct DiracSlice	DiracSlice
typedef struct DiracContext	DiracContext
typedef struct SliceCoeffs	SliceCoeffs

Enumerations
enum	dirac_subband {   subband_ll = 0, subband_hl = 1, subband_lh = 2, subband_hh = 3,   subband_nb }

Variables
AVCodec	ff_dirac_decoder

Detailed Description

Dirac Decoder.

Author

Marco Gerards marco.nosp@m.@gnu.nosp@m..org, David Conrad, Jordi Ortiz nenjo.nosp@m.rdi@.nosp@m.gmail.nosp@m..com

Macro Definition Documentation

CHECKEDREAD

#define CHECKEDREAD	(		dst,
			cond,
			errmsg
	)

Value:

tmp = get_interleaved_ue_golomb(gb); \
    if (cond) { \
        av_log(s->avctx, AV_LOG_ERROR, errmsg); \
        return AVERROR_INVALIDDATA; \
    }\
    dst = tmp;

DATA_UNIT_HEADER_SIZE

#define DATA_UNIT_HEADER_SIZE   13

Dirac Specification -> 9.6 Parse Info Header Syntax.

parse_info() 4 byte start code + byte parse code + 4 byte size + 4 byte previous size

INTRA_DC_PRED

#define INTRA_DC_PRED	(		n,
			type
	)

Value:

static inline void intra_dc_prediction_##n(SubBand *b) \
    { \
        type *buf = (type*)b->ibuf; \
        int x, y; \
        \
        for (x = 1; x < b->width; x++) \
            buf[x] += buf[x-1]; \
        buf += (b->stride >> (1+b->pshift)); \
        \
        for (y = 1; y < b->height; y++) { \
            buf[0] += buf[-(b->stride >> (1+b->pshift))]; \
            \
            for (x = 1; x < b->width; x++) { \
                int pred = buf[x - 1] + buf[x - (b->stride >> (1+b->pshift))] + buf[x - (b->stride >> (1+b->pshift))-1]; \
                buf[x]  += divide3(pred); \
            } \
            buf += (b->stride >> (1+b->pshift)); \
        } \
    } \

Dirac Specification -> 13.3 intra_dc_prediction(band)

PARSE_VALUES

#define PARSE_VALUES	(		type,
			x,
			gb,
			ebits,
			buf1,
			buf2
	)

Value:

type *buf = (type *)buf1; \
    buf[x] = coeff_unpack_golomb(gb, qfactor, qoffset); \
    if (get_bits_count(gb) >= ebits) \
        return; \
    if (buf2) { \
        buf = (type *)buf2; \
        buf[x] = coeff_unpack_golomb(gb, qfactor, qoffset); \
        if (get_bits_count(gb) >= ebits) \
            return; \
    } \

ROLLOFF

#define ROLLOFF

(

i

)

Value:

offset == 1 ? ((i) ? 5 : 3) :        \
    (1 + (6*(i) + offset - 1) / (2*offset - 1))

UNPACK_ARITH

#define UNPACK_ARITH	(		n,
			type
	)

Value:

static inline void coeff_unpack_arith_##n(DiracArith *c, int qfactor, int qoffset, \
                                              SubBand *b, type *buf, int x, int y) \
    { \
        int sign, sign_pred = 0, pred_ctx = CTX_ZPZN_F1; \
        unsigned coeff; \
        const int mstride = -(b->stride >> (1+b->pshift)); \
        if (b->parent) { \
            const type *pbuf = (type *)b->parent->ibuf; \
            const int stride = b->parent->stride >> (1+b->parent->pshift); \
            pred_ctx += !!pbuf[stride * (y>>1) + (x>>1)] << 1; \
        } \
        if (b->orientation == subband_hl) \
            sign_pred = buf[mstride]; \
        if (x) { \
            pred_ctx += !(buf[-1] | buf[mstride] | buf[-1 + mstride]); \
            if (b->orientation == subband_lh) \
                sign_pred = buf[-1]; \
        } else { \
            pred_ctx += !buf[mstride]; \
        } \
        coeff = dirac_get_arith_uint(c, pred_ctx, CTX_COEFF_DATA); \
        if (coeff) { \
            coeff = (coeff * qfactor + qoffset) >> 2; \
            sign  = dirac_get_arith_bit(c, SIGN_CTX(sign_pred)); \
            coeff = (coeff ^ -sign) + sign; \
        } \
        *buf = coeff; \
    } \

Variable Documentation

ff_dirac_decoder

AVCodec ff_dirac_decoder

Initial value:

= {
    .name           = "dirac",
    .long_name      = NULL_IF_CONFIG_SMALL("BBC Dirac VC-2"),
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = AV_CODEC_ID_DIRAC,
    .priv_data_size = sizeof(DiracContext),
    .init           = dirac_decode_init,
    .close          = dirac_decode_end,
    .decode         = dirac_decode_frame,
    .capabilities   = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_SLICE_THREADS | AV_CODEC_CAP_DR1,
    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
    .flush          = dirac_decode_flush,
}