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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];
67 
68 /* Note this is identical to the intra rvlc except that it is reordered. */
71 
72 extern const uint16_t ff_sprite_trajectory_tab[15][2];
73 extern const uint8_t ff_mb_type_b_tab[4][2];
74 
75 /* these matrixes will be permuted for the idct */
76 extern const int16_t ff_mpeg4_default_intra_matrix[64];
77 extern const int16_t ff_mpeg4_default_non_intra_matrix[64];
78 
79 extern const uint8_t ff_mpeg4_y_dc_scale_table[32];
80 extern const uint8_t ff_mpeg4_c_dc_scale_table[32];
81 extern const uint16_t ff_mpeg4_resync_prefix[8];
82 
83 extern const uint8_t ff_mpeg4_dc_threshold[8];
84 
86  int16_t block[6][64],
87  int motion_x, int motion_y);
88 void ff_mpeg4_pred_ac(MpegEncContext * s, int16_t *block, int n,
89  int dir);
91 void ff_mpeg4_encode_picture_header(MpegEncContext *s, int picture_number);
92 
105 
106 /**
107  *
108  * @return the mb_type
109  */
110 int ff_mpeg4_set_direct_mv(MpegEncContext *s, int mx, int my);
111 
113 
114 
115 #if 0 //3IV1 is quite rare and it slows things down a tiny bit
116 #define IS_3IV1 s->codec_tag == AV_RL32("3IV1")
117 #else
118 #define IS_3IV1 0
119 #endif
120 
121 
122 /**
123  * Predict the dc.
124  * encoding quantized level -> quantized diff
125  * decoding quantized diff -> quantized level
126  * @param n block index (0-3 are luma, 4-5 are chroma)
127  * @param dir_ptr pointer to an integer where the prediction direction will be stored
128  */
129 static inline int ff_mpeg4_pred_dc(MpegEncContext * s, int n, int level, int *dir_ptr, int encoding)
130 {
131  int a, b, c, wrap, pred, scale, ret;
132  int16_t *dc_val;
133 
134  /* find prediction */
135  if (n < 4) {
136  scale = s->y_dc_scale;
137  } else {
138  scale = s->c_dc_scale;
139  }
140  if(IS_3IV1)
141  scale= 8;
142 
143  wrap= s->block_wrap[n];
144  dc_val = s->dc_val[0] + s->block_index[n];
145 
146  /* B C
147  * A X
148  */
149  a = dc_val[ - 1];
150  b = dc_val[ - 1 - wrap];
151  c = dc_val[ - wrap];
152 
153  /* outside slice handling (we can't do that by memset as we need the dc for error resilience) */
154  if(s->first_slice_line && n!=3){
155  if(n!=2) b=c= 1024;
156  if(n!=1 && s->mb_x == s->resync_mb_x) b=a= 1024;
157  }
158  if(s->mb_x == s->resync_mb_x && s->mb_y == s->resync_mb_y+1){
159  if(n==0 || n==4 || n==5)
160  b=1024;
161  }
162 
163  if (abs(a - b) < abs(b - c)) {
164  pred = c;
165  *dir_ptr = 1; /* top */
166  } else {
167  pred = a;
168  *dir_ptr = 0; /* left */
169  }
170  /* we assume pred is positive */
171  pred = FASTDIV((pred + (scale >> 1)), scale);
172 
173  if(encoding){
174  ret = level - pred;
175  }else{
176  level += pred;
177  ret= level;
179  if(level<0){
180  av_log(s->avctx, AV_LOG_ERROR, "dc<0 at %dx%d\n", s->mb_x, s->mb_y);
181  return -1;
182  }
183  if(level*scale > 2048 + scale){
184  av_log(s->avctx, AV_LOG_ERROR, "dc overflow at %dx%d\n", s->mb_x, s->mb_y);
185  return -1;
186  }
187  }
188  }
189  level *=scale;
190  if(level&(~2047)){
191  if(level<0)
192  level=0;
193  else if(!(s->workaround_bugs&FF_BUG_DC_CLIP))
194  level=2047;
195  }
196  dc_val[0]= level;
197 
198  return ret;
199 }
200 #endif /* AVCODEC_MPEG4VIDEO_H */