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mpeg4video.h
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1 /*
2  * MPEG-4 encoder/decoder internal header.
3  * Copyright (c) 2000,2001 Fabrice Bellard
4  * Copyright (c) 2002-2010 Michael Niedermayer <michaelni@gmx.at>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #ifndef AVCODEC_MPEG4VIDEO_H
24 #define AVCODEC_MPEG4VIDEO_H
25 
26 #include <stdint.h>
27 
28 #include "get_bits.h"
29 #include "mpegvideo.h"
30 #include "rl.h"
31 
32 // shapes
33 #define RECT_SHAPE 0
34 #define BIN_SHAPE 1
35 #define BIN_ONLY_SHAPE 2
36 #define GRAY_SHAPE 3
37 
38 #define SIMPLE_VO_TYPE 1
39 #define CORE_VO_TYPE 3
40 #define MAIN_VO_TYPE 4
41 #define NBIT_VO_TYPE 5
42 #define ARTS_VO_TYPE 10
43 #define ACE_VO_TYPE 12
44 #define ADV_SIMPLE_VO_TYPE 17
45 
46 // aspect_ratio_info
47 #define EXTENDED_PAR 15
48 
49 //vol_sprite_usage / sprite_enable
50 #define STATIC_SPRITE 1
51 #define GMC_SPRITE 2
52 
53 #define MOTION_MARKER 0x1F001
54 #define DC_MARKER 0x6B001
55 
56 #define VOS_STARTCODE 0x1B0
57 #define USER_DATA_STARTCODE 0x1B2
58 #define GOP_STARTCODE 0x1B3
59 #define VISUAL_OBJ_STARTCODE 0x1B5
60 #define VOP_STARTCODE 0x1B6
61 
62 /* smaller packets likely don't contain a real frame */
63 #define MAX_NVOP_SIZE 19
64 
65 typedef struct Mpeg4DecContext {
67 
68  /// number of bits to represent the fractional part of time
70  int shape;
74  /// sprite trajectory points
75  uint16_t sprite_traj[4][2];
76  /// sprite shift [isChroma]
77  int sprite_shift[2];
78 
79  // reversible vlc
80  int rvlc;
81  /// could this stream contain resync markers
83  /// time distance of first I -> B, used for interlaced B-frames
84  int t_frame;
85 
86  int new_pred;
90 
91  /// QP above which the ac VLC should be used for intra dc
93 
94  /* bug workarounds */
99 
100  /// flag for having shown the warning about invalid Divx B-frames
102  /** does the stream contain the low_delay flag,
103  * used to work around buggy encoders. */
109 
110 /* dc encoding for MPEG-4 */
111 extern const uint8_t ff_mpeg4_DCtab_lum[13][2];
112 extern const uint8_t ff_mpeg4_DCtab_chrom[13][2];
113 
114 extern const uint16_t ff_mpeg4_intra_vlc[103][2];
115 extern const int8_t ff_mpeg4_intra_level[102];
116 extern const int8_t ff_mpeg4_intra_run[102];
117 
119 
120 /* Note this is identical to the intra rvlc except that it is reordered. */
123 
124 extern const uint16_t ff_sprite_trajectory_tab[15][2];
125 extern const uint8_t ff_mb_type_b_tab[4][2];
126 
127 /* these matrixes will be permuted for the idct */
128 extern const int16_t ff_mpeg4_default_intra_matrix[64];
129 extern const int16_t ff_mpeg4_default_non_intra_matrix[64];
130 
131 extern const uint8_t ff_mpeg4_y_dc_scale_table[32];
132 extern const uint8_t ff_mpeg4_c_dc_scale_table[32];
133 extern const uint16_t ff_mpeg4_resync_prefix[8];
134 
135 extern const uint8_t ff_mpeg4_dc_threshold[8];
136 
138  int16_t block[6][64],
139  int motion_x, int motion_y);
140 void ff_mpeg4_pred_ac(MpegEncContext *s, int16_t *block, int n,
141  int dir);
143 int ff_mpeg4_encode_picture_header(MpegEncContext *s, int picture_number);
144 
158 int ff_mpeg4_frame_end(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
159 
160 /**
161  * @return the mb_type
162  */
163 int ff_mpeg4_set_direct_mv(MpegEncContext *s, int mx, int my);
164 
166 
167 #if 0 //3IV1 is quite rare and it slows things down a tiny bit
168 #define IS_3IV1 s->codec_tag == AV_RL32("3IV1")
169 #else
170 #define IS_3IV1 0
171 #endif
172 
173 /**
174  * Predict the dc.
175  * encoding quantized level -> quantized diff
176  * decoding quantized diff -> quantized level
177  * @param n block index (0-3 are luma, 4-5 are chroma)
178  * @param dir_ptr pointer to an integer where the prediction direction will be stored
179  */
180 static inline int ff_mpeg4_pred_dc(MpegEncContext *s, int n, int level,
181  int *dir_ptr, int encoding)
182 {
183  int a, b, c, wrap, pred, scale, ret;
184  int16_t *dc_val;
185 
186  /* find prediction */
187  if (n < 4)
188  scale = s->y_dc_scale;
189  else
190  scale = s->c_dc_scale;
191  if (IS_3IV1)
192  scale = 8;
193 
194  wrap = s->block_wrap[n];
195  dc_val = s->dc_val[0] + s->block_index[n];
196 
197  /* B C
198  * A X
199  */
200  a = dc_val[-1];
201  b = dc_val[-1 - wrap];
202  c = dc_val[-wrap];
203 
204  /* outside slice handling (we can't do that by memset as we need the
205  * dc for error resilience) */
206  if (s->first_slice_line && n != 3) {
207  if (n != 2)
208  b = c = 1024;
209  if (n != 1 && s->mb_x == s->resync_mb_x)
210  b = a = 1024;
211  }
212  if (s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y + 1) {
213  if (n == 0 || n == 4 || n == 5)
214  b = 1024;
215  }
216 
217  if (abs(a - b) < abs(b - c)) {
218  pred = c;
219  *dir_ptr = 1; /* top */
220  } else {
221  pred = a;
222  *dir_ptr = 0; /* left */
223  }
224  /* we assume pred is positive */
225  pred = FASTDIV((pred + (scale >> 1)), scale);
226 
227  if (encoding) {
228  ret = level - pred;
229  } else {
230  level += pred;
231  ret = level;
232  }
233  level *= scale;
234  if (level & (~2047)) {
236  if (level < 0) {
238  "dc<0 at %dx%d\n", s->mb_x, s->mb_y);
239  return -1;
240  }
241  if (level > 2048 + scale) {
243  "dc overflow at %dx%d\n", s->mb_x, s->mb_y);
244  return -1;
245  }
246  }
247  if (level < 0)
248  level = 0;
249  else if (!(s->workaround_bugs & FF_BUG_DC_CLIP))
250  level = 2047;
251  }
252  dc_val[0] = level;
253 
254  return ret;
255 }
256 
257 #endif /* AVCODEC_MPEG4VIDEO_H */
uint16_t sprite_traj[4][2]
sprite trajectory points
Definition: mpeg4video.h:75
#define AV_EF_AGGRESSIVE
consider things that a sane encoder should not do as an error
Definition: avcodec.h:2963
const char * s
Definition: avisynth_c.h:768
int sprite_brightness_change
Definition: mpeg4video.h:72
int resync_marker
could this stream contain resync markers
Definition: mpeg4video.h:82
const int8_t ff_mpeg4_intra_level[102]
Definition: mpeg4data.h:77
const char * b
Definition: vf_curves.c:113
int ff_mpeg4_frame_end(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
#define AV_EF_BITSTREAM
detect bitstream specification deviations
Definition: avcodec.h:2956
mpegvideo header.
int ff_mpeg4_workaround_bugs(AVCodecContext *avctx)
int ff_mpeg4_get_video_packet_prefix_length(MpegEncContext *s)
Definition: mpeg4video.c:30
RLTable.
Definition: rl.h:39
const uint16_t ff_mpeg4_resync_prefix[8]
Definition: mpeg4data.h:368
int encoding
true if we are encoding (vs decoding)
Definition: mpegvideo.h:111
int block_wrap[6]
Definition: mpegvideo.h:294
int cplx_estimation_trash_b
Definition: mpeg4video.h:107
void ff_mpeg4_merge_partitions(MpegEncContext *s)
int vol_sprite_usage
Definition: mpeg4video.h:71
static int16_t block[64]
Definition: dct.c:113
uint8_t
const int16_t ff_mpeg4_default_non_intra_matrix[64]
Definition: mpeg4data.h:348
uint8_t ff_mpeg4_static_rl_table_store[3][2][2 *MAX_RUN+MAX_LEVEL+3]
Definition: mpeg4video.c:28
#define IS_3IV1
Definition: mpeg4video.h:170
int enhancement_type
Definition: mpeg4video.h:87
void ff_mpeg4_encode_video_packet_header(MpegEncContext *s)
int cplx_estimation_trash_p
Definition: mpeg4video.h:106
bitstream reader API header.
RLTable ff_rvlc_rl_inter
Definition: mpeg4data.h:214
int intra_dc_threshold
QP above which the ac VLC should be used for intra dc.
Definition: mpeg4video.h:92
#define MAX_LEVEL
Definition: rl.h:36
static int ff_mpeg4_pred_dc(MpegEncContext *s, int n, int level, int *dir_ptr, int encoding)
Predict the dc.
Definition: mpeg4video.h:180
#define av_log(a,...)
MpegEncContext m
Definition: mpeg4video.h:66
int16_t * dc_val[3]
used for MPEG-4 DC prediction, all 3 arrays must be continuous
Definition: mpegvideo.h:184
const uint16_t ff_mpeg4_intra_vlc[103][2]
Definition: mpeg4data.h:47
const uint8_t ff_mpeg4_DCtab_chrom[13][2]
Definition: mpeg4data.h:41
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
const uint8_t ff_mpeg4_DCtab_lum[13][2]
Definition: mpeg4data.h:35
void ff_mpeg4_pred_ac(MpegEncContext *s, int16_t *block, int n, int dir)
Predict the ac.
Definition: mpeg4videodec.c:63
#define wrap(func)
Definition: neontest.h:65
const uint8_t ff_mpeg4_c_dc_scale_table[32]
Definition: mpeg4data.h:363
int ff_mpeg4_decode_video_packet_header(Mpeg4DecContext *ctx)
Decode the next video packet.
rl header.
void ff_mpeg4_clean_buffers(MpegEncContext *s)
Definition: mpeg4video.c:45
void ff_mpeg4videodec_static_init(void)
const uint16_t ff_sprite_trajectory_tab[15][2]
Definition: mpeg4data.h:326
int resync_mb_x
x position of last resync marker
Definition: mpegvideo.h:356
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:2947
void ff_clean_mpeg4_qscales(MpegEncContext *s)
modify mb_type & qscale so that encoding is actually possible in MPEG-4
int ff_mpeg4_decode_picture_header(Mpeg4DecContext *ctx, GetBitContext *gb)
Decode MPEG-4 headers.
AVFormatContext * ctx
Definition: movenc.c:48
int use_intra_dc_vlc
Definition: mpeg4video.h:89
const uint8_t ff_mpeg4_dc_threshold[8]
Definition: mpeg4data.h:372
int n
Definition: avisynth_c.h:684
int vol_control_parameters
does the stream contain the low_delay flag, used to work around buggy encoders.
Definition: mpeg4video.h:104
const uint8_t ff_mb_type_b_tab[4][2]
Definition: mpeg4data.h:332
int block_index[6]
index to current MB in block based arrays with edges
Definition: mpegvideo.h:293
static const float pred[4]
Definition: siprdata.h:259
int first_slice_line
used in MPEG-4 too to handle resync markers
Definition: mpegvideo.h:433
main external API structure.
Definition: avcodec.h:1659
int cplx_estimation_trash_i
Definition: mpeg4video.h:105
#define FASTDIV(a, b)
Definition: mathops.h:211
RLTable ff_rvlc_rl_intra
Definition: mpeg4data.h:318
void * buf
Definition: avisynth_c.h:690
int showed_packed_warning
flag for having shown the warning about invalid Divx B-frames
Definition: mpeg4video.h:101
int ff_mpeg4_decode_partitions(Mpeg4DecContext *ctx)
Decode the first and second partition.
const int16_t ff_mpeg4_default_intra_matrix[64]
Definition: mpeg4data.h:337
void ff_set_mpeg4_time(MpegEncContext *s)
int sprite_shift[2]
sprite shift [isChroma]
Definition: mpeg4video.h:77
RLTable ff_mpeg4_rl_intra
Definition: mpeg4data.h:109
uint8_t level
Definition: svq3.c:206
MpegEncContext.
Definition: mpegvideo.h:78
#define MAX_RUN
Definition: rl.h:35
struct AVCodecContext * avctx
Definition: mpegvideo.h:95
int t_frame
time distance of first I -> B, used for interlaced B-frames
Definition: mpeg4video.h:84
static double c[64]
void ff_mpeg4_init_direct_mv(MpegEncContext *s)
Definition: mpeg4video.c:71
const int8_t ff_mpeg4_intra_run[102]
Definition: mpeg4data.h:93
const uint8_t ff_mpeg4_y_dc_scale_table[32]
Definition: mpeg4data.h:359
void ff_mpeg4_stuffing(PutBitContext *pbc)
add MPEG-4 stuffing bits (01...1)
void ff_mpeg4_init_partitions(MpegEncContext *s)
int resync_mb_y
y position of last resync marker
Definition: mpegvideo.h:357
void ff_mpeg4_encode_mb(MpegEncContext *s, int16_t block[6][64], int motion_x, int motion_y)
int time_increment_bits
number of bits to represent the fractional part of time
Definition: mpeg4video.h:69
int workaround_bugs
workaround bugs in encoders which cannot be detected automatically
Definition: mpegvideo.h:116
int ff_mpeg4_encode_picture_header(MpegEncContext *s, int picture_number)
int num_sprite_warping_points
Definition: mpeg4video.h:73
#define FF_BUG_DC_CLIP
Definition: avcodec.h:2861
int ff_mpeg4_set_direct_mv(MpegEncContext *s, int mx, int my)
Definition: mpeg4video.c:117