mpeg4videodec.c File Reference

#include "libavutil/internal.h"
#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"
#include "error_resilience.h"
#include "hwconfig.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"
#include "unary.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	STUDIO_INTRA_BITS   9
#define	SET_QPEL_FUNC(postfix1, postfix2)

Functions
static int	decode_studio_vol_header (Mpeg4DecContext *ctx, GetBitContext *gb)
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 void	reset_studio_dc_predictors (MpegEncContext *s)
int	ff_mpeg4_decode_studio_slice_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 void	next_start_code_studio (GetBitContext *gb)
static int	mpeg4_decode_studio_block (MpegEncContext *s, int32_t block[64], int n)
static int	mpeg4_decode_dpcm_macroblock (MpegEncContext *s, int16_t macroblock[256], int n)
static int	mpeg4_decode_studio_mb (MpegEncContext *s, int16_t block_[12][64])
static int	mpeg4_decode_gop_header (MpegEncContext *s, GetBitContext *gb)
static int	mpeg4_decode_profile_level (MpegEncContext *s, GetBitContext *gb, int *profile, int *level)
static int	mpeg4_decode_visual_object (MpegEncContext *s, GetBitContext *gb)
static void	mpeg4_load_default_matrices (MpegEncContext *s)
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)
static int	read_quant_matrix_ext (MpegEncContext *s, GetBitContext *gb)
static void	extension_and_user_data (MpegEncContext *s, GetBitContext *gb, int id)
static void	decode_smpte_tc (Mpeg4DecContext *ctx, GetBitContext *gb)
static int	decode_studio_vop_header (Mpeg4DecContext *ctx, GetBitContext *gb)
	Decode the next studio vop header. More...
static int	decode_studiovisualobject (Mpeg4DecContext *ctx, GetBitContext *gb)
int	ff_mpeg4_decode_picture_header (Mpeg4DecContext *ctx, GetBitContext *gb, int header)
	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	init_studio_vlcs (Mpeg4DecContext *ctx)
static av_cold int	decode_init (AVCodecContext *avctx)
static av_cold int	decode_end (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 uint8_t	ac_state_tab [22][2]
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 46 of file mpeg4videodec.c.

Referenced by ff_mpeg4videodec_static_init(), and mpeg4_decode_sprite_trajectory().

#define DC_VLC_BITS   9

Definition at line 47 of file mpeg4videodec.c.

Referenced by ff_mpeg4videodec_static_init(), and mpeg4_decode_dc().

#define MB_TYPE_B_VLC_BITS   4

Definition at line 48 of file mpeg4videodec.c.

Referenced by ff_mpeg4videodec_static_init(), and mpeg4_decode_mb().

#define STUDIO_INTRA_BITS   9

Definition at line 49 of file mpeg4videodec.c.

Referenced by init_studio_vlcs(), and mpeg4_decode_studio_block().

#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

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

static

Definition at line 3132 of file mpeg4videodec.c.

Referenced by decode_vol_header().

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 69 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 124 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 174 of file mpeg4videodec.c.

Referenced by decode_vop_header(), and ff_mpeg4_decode_video_packet_header().

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

static

Definition at line 431 of file mpeg4videodec.c.

Referenced by decode_vop_header(), and 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 447 of file mpeg4videodec.c.

Referenced by ff_h263_resync().

static void reset_studio_dc_predictors ( MpegEncContext *  s )

static

Definition at line 536 of file mpeg4videodec.c.

Referenced by decode_studio_vop_header(), and ff_mpeg4_decode_studio_slice_header().

int ff_mpeg4_decode_studio_slice_header

(

Mpeg4DecContext *

ctx

)

Decode the next video packet.

Returns

<0 if something went wrong

Definition at line 548 of file mpeg4videodec.c.

Referenced by decode_slice().

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 590 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 643 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 690 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 884 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 977 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 1042 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 1313 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 1400 of file mpeg4videodec.c.

Referenced by decode_init(), and decode_vop_header().

static void next_start_code_studio ( GetBitContext *  gb )

static

Definition at line 1781 of file mpeg4videodec.c.

Referenced by decode_studio_vol_header(), decode_studio_vop_header(), decode_studiovisualobject(), ff_mpeg4_decode_picture_header(), mpeg4_decode_studio_mb(), and read_quant_matrix_ext().

static int mpeg4_decode_studio_block ( MpegEncContext *  s, int32_t  block[64], int  n  )

static

Definition at line 1817 of file mpeg4videodec.c.

Referenced by mpeg4_decode_studio_mb().

static int mpeg4_decode_dpcm_macroblock ( MpegEncContext *  s, int16_t  macroblock[256], int  n  )

static

Definition at line 1935 of file mpeg4videodec.c.

Referenced by mpeg4_decode_studio_mb().

static int mpeg4_decode_studio_mb ( MpegEncContext *  s, int16_t  block_[12][64]  )

static

Definition at line 2018 of file mpeg4videodec.c.

Referenced by decode_studio_vop_header().

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

static

Definition at line 2065 of file mpeg4videodec.c.

Referenced by ff_mpeg4_decode_picture_header().

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

static

Definition at line 2087 of file mpeg4videodec.c.

Referenced by ff_mpeg4_decode_picture_header().

static int mpeg4_decode_visual_object ( MpegEncContext *  s, GetBitContext *  gb  )

static

Definition at line 2101 of file mpeg4videodec.c.

Referenced by ff_mpeg4_decode_picture_header().

static void mpeg4_load_default_matrices ( MpegEncContext *  s )

static

Definition at line 2133 of file mpeg4videodec.c.

Referenced by decode_studio_vop_header(), and decode_vol_header().

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

static

Definition at line 2150 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 2525 of file mpeg4videodec.c.

Referenced by ff_mpeg4_decode_picture_header().

int ff_mpeg4_workaround_bugs

(

AVCodecContext *

avctx

)

Definition at line 2582 of file mpeg4videodec.c.

Referenced by ff_h263_decode_frame().

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

static

Definition at line 2700 of file mpeg4videodec.c.

Referenced by ff_mpeg4_decode_picture_header().

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

static

Definition at line 2974 of file mpeg4videodec.c.

Referenced by extension_and_user_data().

static void extension_and_user_data ( MpegEncContext *  s, GetBitContext *  gb, int  id  )

static

Definition at line 3023 of file mpeg4videodec.c.

Referenced by decode_studio_vol_header(), decode_studio_vop_header(), decode_studiovisualobject(), and ff_mpeg4_decode_picture_header().

static void decode_smpte_tc ( Mpeg4DecContext *  ctx, GetBitContext *  gb  )

static

Definition at line 3040 of file mpeg4videodec.c.

Referenced by decode_studio_vop_header().

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

static

Decode the next studio vop header.

Returns

<0 if something went wrong

Definition at line 3059 of file mpeg4videodec.c.

Referenced by ff_mpeg4_decode_picture_header().

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

static

Definition at line 3114 of file mpeg4videodec.c.

Referenced by ff_mpeg4_decode_picture_header().

int ff_mpeg4_decode_picture_header	(	Mpeg4DecContext *	ctx,
		GetBitContext *	gb,
		int	header
	)

Decode MPEG-4 headers.

Parameters

header

If set the absence of a VOP is not treated as error; otherwise, it is treated as such.

Returns

<0 if an error occurred FRAME_SKIPPED if a not coded VOP is found 0 else

Definition at line 3219 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 3375 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 3401 of file mpeg4videodec.c.

Referenced by ff_h263_decode_frame().

static av_cold int init_studio_vlcs ( Mpeg4DecContext *  ctx )

static

Definition at line 3498 of file mpeg4videodec.c.

Referenced by decode_init().

static av_cold int decode_init ( AVCodecContext *  avctx )

static

Definition at line 3529 of file mpeg4videodec.c.

static av_cold int decode_end ( AVCodecContext *  avctx )

static

Definition at line 3557 of file mpeg4videodec.c.

Variable Documentation

VLC dc_lum

static

Definition at line 53 of file mpeg4videodec.c.

VLC dc_chrom

static

Definition at line 53 of file mpeg4videodec.c.

VLC sprite_trajectory

static

Definition at line 54 of file mpeg4videodec.c.

VLC mb_type_b_vlc

static

Definition at line 55 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 57 of file mpeg4videodec.c.

Referenced by mpeg4_decode_mb().

const uint8_t ac_state_tab[22][2]

static

Initial value:

=
{
    {0, 0},
    {0, 1},
    {1, 1},
    {2, 1},
    {3, 1},
    {4, 1},
    {5, 1},
    {1, 2},
    {2, 2},
    {3, 2},
    {4, 2},
    {5, 2},
    {6, 2},
    {1, 3},
    {2, 4},
    {3, 5},
    {4, 6},
    {5, 7},
    {6, 8},
    {7, 9},
    {8, 10},
    {0, 11}
}

Definition at line 1791 of file mpeg4videodec.c.

Referenced by mpeg4_decode_studio_block().

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 3571 of file mpeg4videodec.c.

const AVClass mpeg4_class

static

Initial value:

= {
    .class_name = "MPEG4 Video Decoder",
    .item_name  = av_default_item_name,
    .option     = mpeg4_options,
    .version    = LIBAVUTIL_VERSION_INT,
}

Definition at line 3577 of file mpeg4videodec.c.

AVCodec ff_mpeg4_decoder

Definition at line 3584 of file mpeg4videodec.c.