h261dec.c File Reference

H.261 decoder. More...

#include "libavutil/mem_internal.h"
#include "libavutil/thread.h"
#include "avcodec.h"
#include "codec_internal.h"
#include "decode.h"
#include "get_bits.h"
#include "mpeg_er.h"
#include "mpegutils.h"
#include "mpegvideo.h"
#include "mpegvideodec.h"
#include "h261.h"

Go to the source code of this file.

Data Structures
struct	H261DecContext

Macros
#define	SLICE_OK   0
#define	SLICE_ERROR   -1
#define	SLICE_END   -2
	end marker found
#define	H261_MBA_VLC_BITS   8
#define	H261_MTYPE_VLC_BITS   6
#define	H261_MV_VLC_BITS   7
#define	H261_CBP_VLC_BITS   9
#define	TCOEFF_VLC_BITS   9
#define	MBA_STUFFING   33
#define	MBA_STARTCODE   34

Functions
static av_cold void	h261_decode_init_static (void)
static av_cold int	h261_decode_init (AVCodecContext *avctx)
static void	h261_init_dest (MpegEncContext *s)
static int	h261_decode_gob_header (H261DecContext *h)
	Decode the group of blocks header or slice header.
static void	h261_decode_mb_skipped (H261DecContext *h, int mba1, int mba2)
	Decode skipped macroblocks.
static int	decode_mv_component (GetBitContext *gb, int v)
static int	h261_decode_block (H261DecContext *h, int16_t *block, int n, int coded)
	Decode a macroblock.
static int	h261_decode_mb (H261DecContext *h)
static int	h261_decode_picture_header (H261DecContext *h, int *is_key)
	Decode the H.261 picture header.
static int	h261_decode_gob (H261DecContext *h)
static int	h261_decode_frame (AVCodecContext *avctx, AVFrame *pict, int *got_frame, AVPacket *avpkt)

Variables
static VLCElem	h261_mba_vlc [540]
static VLCElem	h261_mtype_vlc [80]
static VLCElem	h261_mv_vlc [144]
static VLCElem	h261_cbp_vlc [512]
const FFCodec	ff_h261_decoder

Detailed Description

H.261 decoder.

Definition in file h261dec.c.

Macro Definition Documentation

SLICE_OK

#define SLICE_OK   0

Definition at line 40 of file h261dec.c.

Referenced by ff_h263_decode_mb(), h261_decode_mb(), mpeg4_decode_mb(), mpeg4_decode_partitioned_mb(), mpeg4_decode_studio_mb(), and rv10_decode_packet().

SLICE_ERROR

#define SLICE_ERROR   -1

Definition at line 41 of file h261dec.c.

Referenced by ff_h263_decode_mb(), h261_decode_mb(), and rv10_decode_packet().

SLICE_END

#define SLICE_END   -2

end marker found

Definition at line 42 of file h261dec.c.

Referenced by decode_slice(), ff_h263_decode_mb(), h261_decode_gob(), h261_decode_mb(), mpeg4_decode_mb(), mpeg4_decode_partitioned_mb(), mpeg4_decode_studio_mb(), and rv10_decode_packet().

H261_MBA_VLC_BITS

#define H261_MBA_VLC_BITS   8

Definition at line 44 of file h261dec.c.

Referenced by h261_decode_init_static(), and h261_decode_mb().

H261_MTYPE_VLC_BITS

#define H261_MTYPE_VLC_BITS   6

Definition at line 45 of file h261dec.c.

Referenced by h261_decode_init_static(), and h261_decode_mb().

H261_MV_VLC_BITS

#define H261_MV_VLC_BITS   7

Definition at line 46 of file h261dec.c.

Referenced by decode_mv_component(), and h261_decode_init_static().

H261_CBP_VLC_BITS

#define H261_CBP_VLC_BITS   9

Definition at line 47 of file h261dec.c.

Referenced by h261_decode_init_static(), and h261_decode_mb().

TCOEFF_VLC_BITS

#define TCOEFF_VLC_BITS   9

Definition at line 48 of file h261dec.c.

Referenced by h261_decode_block().

MBA_STUFFING

#define MBA_STUFFING   33

Definition at line 49 of file h261dec.c.

Referenced by h261_decode_gob(), and h261_decode_mb().

MBA_STARTCODE

#define MBA_STARTCODE   34

Definition at line 50 of file h261dec.c.

Referenced by h261_decode_mb().

Function Documentation

h261_decode_init_static()

static av_cold void h261_decode_init_static ( void )

static

Definition at line 72 of file h261dec.c.

Referenced by h261_decode_init().

h261_decode_init()

static av_cold int h261_decode_init ( AVCodecContext * avctx )

static

Definition at line 90 of file h261dec.c.

h261_init_dest()

static void h261_init_dest ( MpegEncContext * s )

inlinestatic

Definition at line 119 of file h261dec.c.

Referenced by h261_decode_mb(), and h261_decode_mb_skipped().

h261_decode_gob_header()

static int h261_decode_gob_header ( H261DecContext * h )

static

Decode the group of blocks header or slice header.

Returns

<0 if an error occurred

Definition at line 132 of file h261dec.c.

Referenced by h261_decode_frame().

h261_decode_mb_skipped()

static void h261_decode_mb_skipped ( H261DecContext * h, int mba1, int mba2 )

static

Decode skipped macroblocks.

Definition at line 186 of file h261dec.c.

Referenced by h261_decode_gob().

decode_mv_component()

static int decode_mv_component ( GetBitContext * gb, int v )

static

Definition at line 223 of file h261dec.c.

Referenced by h261_decode_mb().

h261_decode_block()

static int h261_decode_block ( H261DecContext * h, int16_t * block, int n, int coded )

static

Decode a macroblock.

Returns

<0 if an error occurred

Definition at line 247 of file h261dec.c.

Referenced by h261_decode_mb().

h261_decode_mb()

static int h261_decode_mb ( H261DecContext * h )

static

Definition at line 346 of file h261dec.c.

Referenced by h261_decode_gob().

h261_decode_picture_header()

static int h261_decode_picture_header ( H261DecContext * h, int * is_key )

static

Decode the H.261 picture header.

Returns

<0 if no startcode found

Definition at line 469 of file h261dec.c.

Referenced by h261_decode_frame().

h261_decode_gob()

static int h261_decode_gob ( H261DecContext * h )

static

Definition at line 516 of file h261dec.c.

Referenced by h261_decode_frame().

h261_decode_frame()

static int h261_decode_frame ( AVCodecContext * avctx, AVFrame * pict, int * got_frame, AVPacket * avpkt )

static

Definition at line 543 of file h261dec.c.

Variable Documentation

h261_mba_vlc

VLCElem h261_mba_vlc[540]

static

Definition at line 52 of file h261dec.c.

Referenced by h261_decode_init_static(), and h261_decode_mb().

h261_mtype_vlc

VLCElem h261_mtype_vlc[80]

static

Definition at line 53 of file h261dec.c.

Referenced by h261_decode_init_static(), and h261_decode_mb().

h261_mv_vlc

VLCElem h261_mv_vlc[144]

static

Definition at line 54 of file h261dec.c.

Referenced by decode_mv_component(), and h261_decode_init_static().

h261_cbp_vlc

VLCElem h261_cbp_vlc[512]

static

Definition at line 55 of file h261dec.c.

Referenced by h261_decode_init_static(), and h261_decode_mb().

ff_h261_decoder

const FFCodec ff_h261_decoder

Initial value:

= {
    .p.name         = "h261",
    CODEC_LONG_NAME("H.261"),
    .p.type         = AVMEDIA_TYPE_VIDEO,
    .p.id           = AV_CODEC_ID_H261,
    .priv_data_size = sizeof(H261DecContext),
    .init           = h261_decode_init,
    FF_CODEC_DECODE_CB(h261_decode_frame),
    .close          = ff_mpv_decode_close,
    .p.capabilities = AV_CODEC_CAP_DR1,
    .p.max_lowres   = 3,
    .caps_internal  = FF_CODEC_CAP_SKIP_FRAME_FILL_PARAM,
}

Definition at line 614 of file h261dec.c.