mpeg4videodec.c File Reference

#include "libavutil/internal.h"
#include "libavutil/opt.h"
#include "error_resilience.h"
#include "idctdsp.h"
#include "internal.h"
#include "mpegutils.h"
#include "mpegvideo.h"
#include "mpegvideodata.h"
#include "mpeg4video.h"
#include "h263.h"
#include "profiles.h"
#include "thread.h"
#include "xvididct.h"

Go to the source code of this file.

Macros
#define	UNCHECKED_BITSTREAM_READER   1
#define	SPRITE_TRAJ_VLC_BITS   6
#define	DC_VLC_BITS   9
#define	MB_TYPE_B_VLC_BITS   4
#define	SET_QPEL_FUNC(postfix1, postfix2)

Functions
void	ff_mpeg4_pred_ac (MpegEncContext *s, int16_t *block, int n, int dir)
	Predict the ac. More...
static int	mpeg4_is_resync (Mpeg4DecContext *ctx)
	check if the next stuff is a resync marker or the end. More...
static int	mpeg4_decode_sprite_trajectory (Mpeg4DecContext *ctx, GetBitContext *gb)
static int	decode_new_pred (Mpeg4DecContext *ctx, GetBitContext *gb)
int	ff_mpeg4_decode_video_packet_header (Mpeg4DecContext *ctx)
	Decode the next video packet. More...
static int	get_amv (Mpeg4DecContext *ctx, int n)
	Get the average motion vector for a GMC MB. More...
static int	mpeg4_decode_dc (MpegEncContext *s, int n, int *dir_ptr)
	Decode the dc value. More...
static int	mpeg4_decode_partition_a (Mpeg4DecContext *ctx)
	Decode first partition. More...
static int	mpeg4_decode_partition_b (MpegEncContext *s, int mb_count)
	decode second partition. More...
int	ff_mpeg4_decode_partitions (Mpeg4DecContext *ctx)
	Decode the first and second partition. More...
static int	mpeg4_decode_block (Mpeg4DecContext *ctx, int16_t *block, int n, int coded, int intra, int rvlc)
	Decode a block. More...
static int	mpeg4_decode_partitioned_mb (MpegEncContext *s, int16_t block[6][64])
	decode partition C of one MB. More...
static int	mpeg4_decode_mb (MpegEncContext *s, int16_t block[6][64])
static int	mpeg4_decode_gop_header (MpegEncContext *s, GetBitContext *gb)
static int	mpeg4_decode_profile_level (MpegEncContext *s, GetBitContext *gb)
static int	decode_vol_header (Mpeg4DecContext *ctx, GetBitContext *gb)
static int	decode_user_data (Mpeg4DecContext *ctx, GetBitContext *gb)
	Decode the user data stuff in the header. More...
int	ff_mpeg4_workaround_bugs (AVCodecContext *avctx)
static int	decode_vop_header (Mpeg4DecContext *ctx, GetBitContext *gb)
int	ff_mpeg4_decode_picture_header (Mpeg4DecContext *ctx, GetBitContext *gb)
	Decode MPEG-4 headers. More...
av_cold void	ff_mpeg4videodec_static_init (void)
int	ff_mpeg4_frame_end (AVCodecContext *avctx, const uint8_t *buf, int buf_size)
static av_cold int	decode_init (AVCodecContext *avctx)

Variables
static VLC	dc_lum
static VLC	dc_chrom
static VLC	sprite_trajectory
static VLC	mb_type_b_vlc
static const int	mb_type_b_map [4]
static const AVOption	mpeg4_options []
static const AVClass	mpeg4_class
AVCodec	ff_mpeg4_decoder

Macro Definition Documentation

#define UNCHECKED_BITSTREAM_READER   1

Definition at line 23 of file mpeg4videodec.c.

#define SPRITE_TRAJ_VLC_BITS   6

Definition at line 43 of file mpeg4videodec.c.

Referenced by ff_mpeg4videodec_static_init(), and mpeg4_decode_sprite_trajectory().

#define DC_VLC_BITS   9

Definition at line 44 of file mpeg4videodec.c.

Referenced by ff_mpeg4videodec_static_init(), and mpeg4_decode_dc().

#define MB_TYPE_B_VLC_BITS   4

Definition at line 45 of file mpeg4videodec.c.

Referenced by ff_mpeg4videodec_static_init(), and mpeg4_decode_mb().

#define SET_QPEL_FUNC	(		postfix1,
			postfix2
	)

Value:

s->qdsp.put_        ## postfix1 = ff_put_        ## postfix2;   \
    s->qdsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2;   \
    s->qdsp.avg_        ## postfix1 = ff_avg_        ## postfix2;

Referenced by ff_mpeg4_workaround_bugs().

Function Documentation

void ff_mpeg4_pred_ac	(	MpegEncContext *	s,
		int16_t *	block,
		int	n,
		int	dir
	)

Predict the ac.

Parameters

n	block index (0-3 are luma, 4-5 are chroma)
dir	the ac prediction direction

Definition at line 63 of file mpeg4videodec.c.

Referenced by ff_msmpeg4_decode_block(), and mpeg4_decode_block().

static int mpeg4_is_resync ( Mpeg4DecContext *  ctx )

inlinestatic

check if the next stuff is a resync marker or the end.

Returns

0 if not

Definition at line 118 of file mpeg4videodec.c.

Referenced by mpeg4_decode_mb(), and mpeg4_decode_partitioned_mb().

static int mpeg4_decode_sprite_trajectory ( Mpeg4DecContext *  ctx, GetBitContext *  gb  )

static

Definition at line 168 of file mpeg4videodec.c.

Referenced by ff_mpeg4_decode_video_packet_header().

static int decode_new_pred ( Mpeg4DecContext *  ctx, GetBitContext *  gb  )

static

Definition at line 421 of file mpeg4videodec.c.

Referenced by ff_mpeg4_decode_video_packet_header().

int ff_mpeg4_decode_video_packet_header

(

Mpeg4DecContext *

ctx

)

Decode the next video packet.

Returns

<0 if something went wrong

Definition at line 437 of file mpeg4videodec.c.

Referenced by ff_h263_resync().

static int get_amv ( Mpeg4DecContext *  ctx, int  n  )

inlinestatic

Get the average motion vector for a GMC MB.

Parameters

n	either 0 for the x component or 1 for y

Returns

the average MV for a GMC MB

Definition at line 531 of file mpeg4videodec.c.

Referenced by mpeg4_decode_mb(), and mpeg4_decode_partition_a().

static int mpeg4_decode_dc ( MpegEncContext *  s, int  n, int *  dir_ptr  )

inlinestatic

Decode the dc value.

Parameters

n	block index (0-3 are luma, 4-5 are chroma)
dir_ptr	the prediction direction will be stored here

Returns

the quantized dc

Definition at line 584 of file mpeg4videodec.c.

Referenced by mpeg4_decode_block(), mpeg4_decode_partition_a(), and mpeg4_decode_partition_b().

static int mpeg4_decode_partition_a ( Mpeg4DecContext *  ctx )

static

Decode first partition.

Returns

number of MBs decoded or <0 if an error occurred

Definition at line 631 of file mpeg4videodec.c.

Referenced by ff_mpeg4_decode_partitions().

static int mpeg4_decode_partition_b ( MpegEncContext *  s, int  mb_count  )

static

decode second partition.

Returns

<0 if an error occurred

Definition at line 825 of file mpeg4videodec.c.

Referenced by ff_mpeg4_decode_partitions().

int ff_mpeg4_decode_partitions

(

Mpeg4DecContext *

ctx

)

Decode the first and second partition.

Returns

<0 if error (and sets error type in the error_status_table)

Definition at line 918 of file mpeg4videodec.c.

Referenced by decode_slice().

static int mpeg4_decode_block ( Mpeg4DecContext *  ctx, int16_t *  block, int  n, int  coded, int  intra, int  rvlc  )

inlinestatic

Decode a block.

Returns

<0 if an error occurred

Definition at line 981 of file mpeg4videodec.c.

Referenced by mpeg4_decode_mb(), and mpeg4_decode_partitioned_mb().

static int mpeg4_decode_partitioned_mb ( MpegEncContext *  s, int16_t  block[6][64]  )

static

decode partition C of one MB.

Returns

<0 if an error occurred

Definition at line 1252 of file mpeg4videodec.c.

Referenced by decode_vop_header().

static int mpeg4_decode_mb ( MpegEncContext *  s, int16_t  block[6][64]  )

static

Definition at line 1337 of file mpeg4videodec.c.

Referenced by decode_init(), and decode_vop_header().

static int mpeg4_decode_gop_header ( MpegEncContext *  s, GetBitContext *  gb  )

static

Definition at line 1716 of file mpeg4videodec.c.

Referenced by ff_mpeg4_decode_picture_header().

static int mpeg4_decode_profile_level ( MpegEncContext *  s, GetBitContext *  gb  )

static

Definition at line 1738 of file mpeg4videodec.c.

Referenced by ff_mpeg4_decode_picture_header().

static int decode_vol_header ( Mpeg4DecContext *  ctx, GetBitContext *  gb  )

static

Definition at line 1752 of file mpeg4videodec.c.

Referenced by ff_mpeg4_decode_picture_header().

static int decode_user_data ( Mpeg4DecContext *  ctx, GetBitContext *  gb  )

static

Decode the user data stuff in the header.

Also initializes divx/xvid/lavc_version/build.

Definition at line 2120 of file mpeg4videodec.c.

Referenced by ff_mpeg4_decode_picture_header().

int ff_mpeg4_workaround_bugs

(

AVCodecContext *

avctx

)

Definition at line 2177 of file mpeg4videodec.c.

Referenced by ff_h263_decode_frame().

static int decode_vop_header ( Mpeg4DecContext *  ctx, GetBitContext *  gb  )

static

Definition at line 2295 of file mpeg4videodec.c.

Referenced by ff_mpeg4_decode_picture_header().

int ff_mpeg4_decode_picture_header	(	Mpeg4DecContext *	ctx,
		GetBitContext *	gb
	)

Decode MPEG-4 headers.

Returns

<0 if no VOP found (or a damaged one) FRAME_SKIPPED if a not coded VOP is found 0 if a VOP is found

Definition at line 2575 of file mpeg4videodec.c.

Referenced by ff_h263_decode_frame(), and mpeg4_decode_header().

av_cold void ff_mpeg4videodec_static_init

(

void

)

Definition at line 2698 of file mpeg4videodec.c.

Referenced by decode_init(), and mpeg4video_parse_init().

int ff_mpeg4_frame_end	(	AVCodecContext *	avctx,
		const uint8_t *	buf,
		int	buf_size
	)

Definition at line 2724 of file mpeg4videodec.c.

Referenced by ff_h263_decode_frame().

static av_cold int decode_init ( AVCodecContext *  avctx )

static

Definition at line 2795 of file mpeg4videodec.c.

Variable Documentation

VLC dc_lum

static

Definition at line 47 of file mpeg4videodec.c.

VLC dc_chrom

static

Definition at line 47 of file mpeg4videodec.c.

VLC sprite_trajectory

static

Definition at line 48 of file mpeg4videodec.c.

VLC mb_type_b_vlc

static

Definition at line 49 of file mpeg4videodec.c.

const int mb_type_b_map[4]

static

Initial value:

= {
    MB_TYPE_DIRECT2 | MB_TYPE_L0L1,
    MB_TYPE_L0L1    | MB_TYPE_16x16,
    MB_TYPE_L1      | MB_TYPE_16x16,
    MB_TYPE_L0      | MB_TYPE_16x16,
}

Definition at line 51 of file mpeg4videodec.c.

Referenced by mpeg4_decode_mb().

const AVOption mpeg4_options[]

static

Initial value:

= {
    {"quarter_sample", "1/4 subpel MC", 0x42, AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, 0},
    {"divx_packed", "divx style packed b frames", 0x42, AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, 0},
    {NULL}
}

Definition at line 2822 of file mpeg4videodec.c.

const AVClass mpeg4_class

static

Initial value:

= {
    "MPEG4 Video Decoder",
    av_default_item_name,
    mpeg4_options,
    LIBAVUTIL_VERSION_INT,
}

Definition at line 2828 of file mpeg4videodec.c.

AVCodec ff_mpeg4_decoder

Initial value:

= {
    .name                  = "mpeg4",
    .long_name             = NULL_IF_CONFIG_SMALL("MPEG-4 part 2"),
    .type                  = AVMEDIA_TYPE_VIDEO,
    .id                    = AV_CODEC_ID_MPEG4,
    .priv_data_size        = sizeof(Mpeg4DecContext),
    .init                  = decode_init,
    .close                 = ff_h263_decode_end,
    .decode                = ff_h263_decode_frame,
    .capabilities          = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 |
                             AV_CODEC_CAP_TRUNCATED | AV_CODEC_CAP_DELAY |
                             AV_CODEC_CAP_FRAME_THREADS,
    .caps_internal         = FF_CODEC_CAP_SKIP_FRAME_FILL_PARAM,
    .flush                 = ff_mpeg_flush,
    .max_lowres            = 3,
    .pix_fmts              = ff_h263_hwaccel_pixfmt_list_420,
    .profiles              = NULL_IF_CONFIG_SMALL(ff_mpeg4_video_profiles),
    .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg4_update_thread_context),
    .priv_class = &mpeg4_class,
}

Definition at line 2835 of file mpeg4videodec.c.