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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 // The defines below define the number of bits that are read at once for
30 // reading vlc values. Changing these may improve speed and data cache needs
31 // be aware though that decreasing them may need the number of stages that is
32 // passed to get_vlc* to be increased.
33 #define INTRA_MCBPC_VLC_BITS 6
34 #define INTER_MCBPC_VLC_BITS 7
35 #define CBPY_VLC_BITS 6
36 #define TEX_VLC_BITS 9
37 
38 extern const AVRational ff_h263_pixel_aspect[16];
39 extern const uint8_t ff_h263_cbpy_tab[16][2];
40 
41 extern const uint8_t ff_cbpc_b_tab[4][2];
42 
43 extern const uint8_t ff_mvtab[33][2];
44 
45 extern const uint8_t ff_h263_intra_MCBPC_code[9];
46 extern const uint8_t ff_h263_intra_MCBPC_bits[9];
47 
48 extern const uint8_t ff_h263_inter_MCBPC_code[28];
49 extern const uint8_t ff_h263_inter_MCBPC_bits[28];
50 extern const uint8_t ff_h263_mbtype_b_tab[15][2];
51 
52 extern VLC ff_h263_intra_MCBPC_vlc;
53 extern VLC ff_h263_inter_MCBPC_vlc;
54 extern VLC ff_h263_cbpy_vlc;
55 
56 extern RLTable ff_h263_rl_inter;
57 
58 extern RLTable ff_rl_intra_aic;
59 
60 extern const uint16_t ff_h263_format[8][2];
61 extern const uint8_t ff_modified_quant_tab[2][32];
62 extern const uint16_t ff_mba_max[6];
63 extern const uint8_t ff_mba_length[7];
64 
65 extern uint8_t ff_h263_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
66 
67 
68 int ff_h263_decode_motion(MpegEncContext * s, int pred, int f_code);
69 av_const int ff_h263_aspect_to_info(AVRational aspect);
70 int ff_h263_decode_init(AVCodecContext *avctx);
71 int ff_h263_decode_frame(AVCodecContext *avctx,
72  void *data, int *got_frame,
73  AVPacket *avpkt);
74 int ff_h263_decode_end(AVCodecContext *avctx);
75 void ff_h263_encode_mb(MpegEncContext *s,
76  DCTELEM block[6][64],
77  int motion_x, int motion_y);
78 void ff_h263_encode_picture_header(MpegEncContext *s, int picture_number);
79 void ff_h263_encode_gob_header(MpegEncContext * s, int mb_line);
80 int16_t *ff_h263_pred_motion(MpegEncContext * s, int block, int dir,
81  int *px, int *py);
82 void ff_h263_encode_init(MpegEncContext *s);
83 void ff_h263_decode_init_vlc(MpegEncContext *s);
84 int ff_h263_decode_picture_header(MpegEncContext *s);
85 int ff_h263_decode_gob_header(MpegEncContext *s);
86 void ff_h263_update_motion_val(MpegEncContext * s);
87 void ff_h263_loop_filter(MpegEncContext * s);
88 int ff_h263_decode_mba(MpegEncContext *s);
89 void ff_h263_encode_mba(MpegEncContext *s);
90 void ff_init_qscale_tab(MpegEncContext *s);
91 int ff_h263_pred_dc(MpegEncContext * s, int n, int16_t **dc_val_ptr);
92 void ff_h263_pred_acdc(MpegEncContext * s, DCTELEM *block, int n);
93 
94 
95 /**
96  * Print picture info if FF_DEBUG_PICT_INFO is set.
97  */
98 void ff_h263_show_pict_info(MpegEncContext *s);
99 
100 int ff_intel_h263_decode_picture_header(MpegEncContext *s);
101 int ff_h263_decode_mb(MpegEncContext *s,
102  DCTELEM block[6][64]);
103 
104 /**
105  * Return the value of the 3bit "source format" syntax element.
106  * This represents some standard picture dimensions or indicates that
107  * width&height are explicitly stored later.
108  */
109 int av_const h263_get_picture_format(int width, int height);
110 
111 void ff_clean_h263_qscales(MpegEncContext *s);
112 int ff_h263_resync(MpegEncContext *s);
113 const uint8_t *ff_h263_find_resync_marker(MpegEncContext *s, const uint8_t *p, const uint8_t *end);
114 int ff_h263_get_gob_height(MpegEncContext *s);
115 void ff_h263_encode_motion(MpegEncContext * s, int val, int f_code);
116 
117 
118 static inline int h263_get_motion_length(MpegEncContext * s, int val, int f_code){
119  int l, bit_size, code;
120 
121  if (val == 0) {
122  return ff_mvtab[0][1];
123  } else {
124  bit_size = f_code - 1;
125  /* modulo encoding */
126  l= INT_BIT - 6 - bit_size;
127  val = (val<<l)>>l;
128  val--;
129  code = (val >> bit_size) + 1;
130 
131  return ff_mvtab[code][1] + 1 + bit_size;
132  }
133 }
134 
135 static inline void ff_h263_encode_motion_vector(MpegEncContext * s, int x, int y, int f_code){
136  if(s->flags2 & CODEC_FLAG2_NO_OUTPUT){
137  skip_put_bits(&s->pb,
138  h263_get_motion_length(s, x, f_code)
139  +h263_get_motion_length(s, y, f_code));
140  }else{
141  ff_h263_encode_motion(s, x, f_code);
142  ff_h263_encode_motion(s, y, f_code);
143  }
144 }
145 
146 static inline int get_p_cbp(MpegEncContext * s,
147  DCTELEM block[6][64],
148  int motion_x, int motion_y){
149  int cbp, i;
150 
151  if (s->mpv_flags & FF_MPV_FLAG_CBP_RD) {
152  int best_cbpy_score= INT_MAX;
153  int best_cbpc_score= INT_MAX;
154  int cbpc = (-1), cbpy= (-1);
155  const int offset= (s->mv_type==MV_TYPE_16X16 ? 0 : 16) + (s->dquant ? 8 : 0);
156  const int lambda= s->lambda2 >> (FF_LAMBDA_SHIFT - 6);
157 
158  for(i=0; i<4; i++){
159  int score= ff_h263_inter_MCBPC_bits[i + offset] * lambda;
160  if(i&1) score += s->coded_score[5];
161  if(i&2) score += s->coded_score[4];
162 
163  if(score < best_cbpc_score){
164  best_cbpc_score= score;
165  cbpc= i;
166  }
167  }
168 
169  for(i=0; i<16; i++){
170  int score= ff_h263_cbpy_tab[i ^ 0xF][1] * lambda;
171  if(i&1) score += s->coded_score[3];
172  if(i&2) score += s->coded_score[2];
173  if(i&4) score += s->coded_score[1];
174  if(i&8) score += s->coded_score[0];
175 
176  if(score < best_cbpy_score){
177  best_cbpy_score= score;
178  cbpy= i;
179  }
180  }
181  cbp= cbpc + 4*cbpy;
182  if ((motion_x | motion_y | s->dquant) == 0 && s->mv_type==MV_TYPE_16X16){
183  if(best_cbpy_score + best_cbpc_score + 2*lambda >= 0)
184  cbp= 0;
185  }
186 
187  for (i = 0; i < 6; i++) {
188  if (s->block_last_index[i] >= 0 && ((cbp >> (5 - i))&1)==0 ){
189  s->block_last_index[i]= -1;
190  s->dsp.clear_block(s->block[i]);
191  }
192  }
193  }else{
194  cbp= 0;
195  for (i = 0; i < 6; i++) {
196  if (s->block_last_index[i] >= 0)
197  cbp |= 1 << (5 - i);
198  }
199  }
200  return cbp;
201 }
202 
203 static inline void memsetw(short *tab, int val, int n)
204 {
205  int i;
206  for(i=0;i<n;i++)
207  tab[i] = val;
208 }
209 
210 #endif /* AVCODEC_H263_H */
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