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h263.h
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1 /*
2  * H263 internal header
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 #ifndef AVCODEC_H263_H
21 #define AVCODEC_H263_H
22 
23 #include <stdint.h>
24 #include "libavutil/rational.h"
25 #include "get_bits.h"
26 #include "mpegvideo.h"
27 #include "rl.h"
28 
29 #if !FF_API_ASPECT_EXTENDED
30 #define FF_ASPECT_EXTENDED 15
31 #endif
32 
33 // The defines below define the number of bits that are read at once for
34 // reading vlc values. Changing these may improve speed and data cache needs
35 // be aware though that decreasing them may need the number of stages that is
36 // passed to get_vlc* to be increased.
37 #define INTRA_MCBPC_VLC_BITS 6
38 #define INTER_MCBPC_VLC_BITS 7
39 #define CBPY_VLC_BITS 6
40 #define TEX_VLC_BITS 9
41 
42 extern const AVRational ff_h263_pixel_aspect[16];
43 extern const uint8_t ff_h263_cbpy_tab[16][2];
44 
45 extern const uint8_t ff_cbpc_b_tab[4][2];
46 
47 extern const uint8_t ff_mvtab[33][2];
48 
49 extern const uint8_t ff_h263_intra_MCBPC_code[9];
50 extern const uint8_t ff_h263_intra_MCBPC_bits[9];
51 
52 extern const uint8_t ff_h263_inter_MCBPC_code[28];
53 extern const uint8_t ff_h263_inter_MCBPC_bits[28];
54 extern const uint8_t ff_h263_mbtype_b_tab[15][2];
55 
58 extern VLC ff_h263_cbpy_vlc;
59 
60 extern const uint16_t ff_inter_vlc[103][2];
61 extern const int8_t ff_inter_level[102];
62 extern const int8_t ff_inter_run[102];
63 
65 
67 
68 extern const uint16_t ff_h263_format[8][2];
69 extern const uint8_t ff_modified_quant_tab[2][32];
70 extern const uint16_t ff_mba_max[6];
71 extern const uint8_t ff_mba_length[7];
72 
74 
76 
77 
78 int ff_h263_decode_motion(MpegEncContext * s, int pred, int f_code);
82  void *data, int *got_frame,
83  AVPacket *avpkt);
86  int16_t block[6][64],
87  int motion_x, int motion_y);
88 void ff_h263_encode_picture_header(MpegEncContext *s, int picture_number);
89 void ff_h263_encode_gob_header(MpegEncContext * s, int mb_line);
90 int16_t *ff_h263_pred_motion(MpegEncContext * s, int block, int dir,
91  int *px, int *py);
93 void ff_h263_decode_init_vlc(void);
101 int ff_h263_pred_dc(MpegEncContext * s, int n, int16_t **dc_val_ptr);
102 void ff_h263_pred_acdc(MpegEncContext * s, int16_t *block, int n);
103 
104 
105 /**
106  * Print picture info if FF_DEBUG_PICT_INFO is set.
107  */
109 
112  int16_t block[6][64]);
113 
114 /**
115  * Return the value of the 3bit "source format" syntax element.
116  * This represents some standard picture dimensions or indicates that
117  * width&height are explicitly stored later.
118  */
120 
124 void ff_h263_encode_motion(MpegEncContext * s, int val, int f_code);
125 
126 
127 static inline int h263_get_motion_length(MpegEncContext * s, int val, int f_code){
128  int l, bit_size, code;
129 
130  if (val == 0) {
131  return ff_mvtab[0][1];
132  } else {
133  bit_size = f_code - 1;
134  /* modulo encoding */
135  l= INT_BIT - 6 - bit_size;
136  val = (val<<l)>>l;
137  val--;
138  code = (val >> bit_size) + 1;
139 
140  return ff_mvtab[code][1] + 1 + bit_size;
141  }
142 }
143 
144 static inline void ff_h263_encode_motion_vector(MpegEncContext * s, int x, int y, int f_code){
145  if(s->flags2 & CODEC_FLAG2_NO_OUTPUT){
146  skip_put_bits(&s->pb,
147  h263_get_motion_length(s, x, f_code)
148  +h263_get_motion_length(s, y, f_code));
149  }else{
150  ff_h263_encode_motion(s, x, f_code);
151  ff_h263_encode_motion(s, y, f_code);
152  }
153 }
154 
155 static inline int get_p_cbp(MpegEncContext * s,
156  int16_t block[6][64],
157  int motion_x, int motion_y){
158  int cbp, i;
159 
160  if (s->mpv_flags & FF_MPV_FLAG_CBP_RD) {
161  int best_cbpy_score= INT_MAX;
162  int best_cbpc_score= INT_MAX;
163  int cbpc = (-1), cbpy= (-1);
164  const int offset= (s->mv_type==MV_TYPE_16X16 ? 0 : 16) + (s->dquant ? 8 : 0);
165  const int lambda= s->lambda2 >> (FF_LAMBDA_SHIFT - 6);
166 
167  for(i=0; i<4; i++){
168  int score= ff_h263_inter_MCBPC_bits[i + offset] * lambda;
169  if(i&1) score += s->coded_score[5];
170  if(i&2) score += s->coded_score[4];
171 
172  if(score < best_cbpc_score){
173  best_cbpc_score= score;
174  cbpc= i;
175  }
176  }
177 
178  for(i=0; i<16; i++){
179  int score= ff_h263_cbpy_tab[i ^ 0xF][1] * lambda;
180  if(i&1) score += s->coded_score[3];
181  if(i&2) score += s->coded_score[2];
182  if(i&4) score += s->coded_score[1];
183  if(i&8) score += s->coded_score[0];
184 
185  if(score < best_cbpy_score){
186  best_cbpy_score= score;
187  cbpy= i;
188  }
189  }
190  cbp= cbpc + 4*cbpy;
191  if ((motion_x | motion_y | s->dquant) == 0 && s->mv_type==MV_TYPE_16X16){
192  if(best_cbpy_score + best_cbpc_score + 2*lambda >= 0)
193  cbp= 0;
194  }
195 
196  for (i = 0; i < 6; i++) {
197  if (s->block_last_index[i] >= 0 && ((cbp >> (5 - i))&1)==0 ){
198  s->block_last_index[i]= -1;
199  s->dsp.clear_block(s->block[i]);
200  }
201  }
202  }else{
203  cbp= 0;
204  for (i = 0; i < 6; i++) {
205  if (s->block_last_index[i] >= 0)
206  cbp |= 1 << (5 - i);
207  }
208  }
209  return cbp;
210 }
211 
212 static inline void memsetw(short *tab, int val, int n)
213 {
214  int i;
215  for(i=0;i<n;i++)
216  tab[i] = val;
217 }
218 
219 #endif /* AVCODEC_H263_H */