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mpeg4video.h
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1 /*
2  * MPEG4 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 #include "get_bits.h"
28 #include "mpegvideo.h"
29 #include "rl.h"
30 
31 // shapes
32 #define RECT_SHAPE 0
33 #define BIN_SHAPE 1
34 #define BIN_ONLY_SHAPE 2
35 #define GRAY_SHAPE 3
36 
37 #define SIMPLE_VO_TYPE 1
38 #define CORE_VO_TYPE 3
39 #define MAIN_VO_TYPE 4
40 #define NBIT_VO_TYPE 5
41 #define ARTS_VO_TYPE 10
42 #define ACE_VO_TYPE 12
43 #define ADV_SIMPLE_VO_TYPE 17
44 
45 // aspect_ratio_info
46 #define EXTENDED_PAR 15
47 
48 //vol_sprite_usage / sprite_enable
49 #define STATIC_SPRITE 1
50 #define GMC_SPRITE 2
51 
52 #define MOTION_MARKER 0x1F001
53 #define DC_MARKER 0x6B001
54 
55 #define VOS_STARTCODE 0x1B0
56 #define USER_DATA_STARTCODE 0x1B2
57 #define GOP_STARTCODE 0x1B3
58 #define VISUAL_OBJ_STARTCODE 0x1B5
59 #define VOP_STARTCODE 0x1B6
60 
61 /* dc encoding for mpeg4 */
62 extern const uint8_t ff_mpeg4_DCtab_lum[13][2];
63 extern const uint8_t ff_mpeg4_DCtab_chrom[13][2];
64 
65 extern const uint16_t ff_mpeg4_intra_vlc[103][2];
66 extern const int8_t ff_mpeg4_intra_level[102];
67 extern const int8_t ff_mpeg4_intra_run[102];
68 
70 
71 /* Note this is identical to the intra rvlc except that it is reordered. */
74 
75 extern const uint16_t ff_sprite_trajectory_tab[15][2];
76 extern const uint8_t ff_mb_type_b_tab[4][2];
77 
78 /* these matrixes will be permuted for the idct */
79 extern const int16_t ff_mpeg4_default_intra_matrix[64];
80 extern const int16_t ff_mpeg4_default_non_intra_matrix[64];
81 
82 extern const uint8_t ff_mpeg4_y_dc_scale_table[32];
83 extern const uint8_t ff_mpeg4_c_dc_scale_table[32];
84 extern const uint16_t ff_mpeg4_resync_prefix[8];
85 
86 extern const uint8_t ff_mpeg4_dc_threshold[8];
87 
89  int16_t block[6][64],
90  int motion_x, int motion_y);
91 void ff_mpeg4_pred_ac(MpegEncContext * s, int16_t *block, int n,
92  int dir);
94 void ff_mpeg4_encode_picture_header(MpegEncContext *s, int picture_number);
95 
108 
109 /**
110  *
111  * @return the mb_type
112  */
113 int ff_mpeg4_set_direct_mv(MpegEncContext *s, int mx, int my);
114 
116 
117 
118 #if 0 //3IV1 is quite rare and it slows things down a tiny bit
119 #define IS_3IV1 s->codec_tag == AV_RL32("3IV1")
120 #else
121 #define IS_3IV1 0
122 #endif
123 
124 
125 /**
126  * Predict the dc.
127  * encoding quantized level -> quantized diff
128  * decoding quantized diff -> quantized level
129  * @param n block index (0-3 are luma, 4-5 are chroma)
130  * @param dir_ptr pointer to an integer where the prediction direction will be stored
131  */
132 static inline int ff_mpeg4_pred_dc(MpegEncContext * s, int n, int level, int *dir_ptr, int encoding)
133 {
134  int a, b, c, wrap, pred, scale, ret;
135  int16_t *dc_val;
136 
137  /* find prediction */
138  if (n < 4) {
139  scale = s->y_dc_scale;
140  } else {
141  scale = s->c_dc_scale;
142  }
143  if(IS_3IV1)
144  scale= 8;
145 
146  wrap= s->block_wrap[n];
147  dc_val = s->dc_val[0] + s->block_index[n];
148 
149  /* B C
150  * A X
151  */
152  a = dc_val[ - 1];
153  b = dc_val[ - 1 - wrap];
154  c = dc_val[ - wrap];
155 
156  /* outside slice handling (we can't do that by memset as we need the dc for error resilience) */
157  if(s->first_slice_line && n!=3){
158  if(n!=2) b=c= 1024;
159  if(n!=1 && s->mb_x == s->resync_mb_x) b=a= 1024;
160  }
161  if(s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y+1){
162  if(n==0 || n==4 || n==5)
163  b=1024;
164  }
165 
166  if (abs(a - b) < abs(b - c)) {
167  pred = c;
168  *dir_ptr = 1; /* top */
169  } else {
170  pred = a;
171  *dir_ptr = 0; /* left */
172  }
173  /* we assume pred is positive */
174  pred = FASTDIV((pred + (scale >> 1)), scale);
175 
176  if(encoding){
177  ret = level - pred;
178  }else{
179  level += pred;
180  ret= level;
182  if(level<0){
183  av_log(s->avctx, AV_LOG_ERROR, "dc<0 at %dx%d\n", s->mb_x, s->mb_y);
184  return -1;
185  }
186  if(level*scale > 2048 + scale){
187  av_log(s->avctx, AV_LOG_ERROR, "dc overflow at %dx%d\n", s->mb_x, s->mb_y);
188  return -1;
189  }
190  }
191  }
192  level *=scale;
193  if(level&(~2047)){
194  if(level<0)
195  level=0;
196  else if(!(s->workaround_bugs&FF_BUG_DC_CLIP))
197  level=2047;
198  }
199  dc_val[0]= level;
200 
201  return ret;
202 }
203 #endif /* AVCODEC_MPEG4VIDEO_H */