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h263.c
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1 /*
2  * H263/MPEG4 backend for encoder and decoder
3  * Copyright (c) 2000,2001 Fabrice Bellard
4  * H263+ support.
5  * Copyright (c) 2001 Juan J. Sierralta P
6  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
7  *
8  * This file is part of FFmpeg.
9  *
10  * FFmpeg is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU Lesser General Public
12  * License as published by the Free Software Foundation; either
13  * version 2.1 of the License, or (at your option) any later version.
14  *
15  * FFmpeg is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18  * Lesser General Public License for more details.
19  *
20  * You should have received a copy of the GNU Lesser General Public
21  * License along with FFmpeg; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23  */
24 
25 /**
26  * @file
27  * h263/mpeg4 codec.
28  */
29 
30 #include <limits.h>
31 
32 #include "avcodec.h"
33 #include "mpegvideo.h"
34 #include "h263.h"
35 #include "h263data.h"
36 #include "mathops.h"
37 #include "mpegutils.h"
38 #include "unary.h"
39 #include "flv.h"
40 #include "mpeg4video.h"
41 
42 
44 
45 
47  const int mb_xy = s->mb_y * s->mb_stride + s->mb_x;
48  //FIXME a lot of that is only needed for !low_delay
49  const int wrap = s->b8_stride;
50  const int xy = s->block_index[0];
51 
53 
54  if(s->mv_type != MV_TYPE_8X8){
55  int motion_x, motion_y;
56  if (s->mb_intra) {
57  motion_x = 0;
58  motion_y = 0;
59  } else if (s->mv_type == MV_TYPE_16X16) {
60  motion_x = s->mv[0][0][0];
61  motion_y = s->mv[0][0][1];
62  } else /*if (s->mv_type == MV_TYPE_FIELD)*/ {
63  int i;
64  motion_x = s->mv[0][0][0] + s->mv[0][1][0];
65  motion_y = s->mv[0][0][1] + s->mv[0][1][1];
66  motion_x = (motion_x>>1) | (motion_x&1);
67  for(i=0; i<2; i++){
68  s->p_field_mv_table[i][0][mb_xy][0]= s->mv[0][i][0];
69  s->p_field_mv_table[i][0][mb_xy][1]= s->mv[0][i][1];
70  }
71  s->current_picture.ref_index[0][4*mb_xy ] =
72  s->current_picture.ref_index[0][4*mb_xy + 1] = s->field_select[0][0];
73  s->current_picture.ref_index[0][4*mb_xy + 2] =
74  s->current_picture.ref_index[0][4*mb_xy + 3] = s->field_select[0][1];
75  }
76 
77  /* no update if 8X8 because it has been done during parsing */
78  s->current_picture.motion_val[0][xy][0] = motion_x;
79  s->current_picture.motion_val[0][xy][1] = motion_y;
80  s->current_picture.motion_val[0][xy + 1][0] = motion_x;
81  s->current_picture.motion_val[0][xy + 1][1] = motion_y;
82  s->current_picture.motion_val[0][xy + wrap][0] = motion_x;
83  s->current_picture.motion_val[0][xy + wrap][1] = motion_y;
84  s->current_picture.motion_val[0][xy + 1 + wrap][0] = motion_x;
85  s->current_picture.motion_val[0][xy + 1 + wrap][1] = motion_y;
86  }
87 
88  if(s->encoding){ //FIXME encoding MUST be cleaned up
89  if (s->mv_type == MV_TYPE_8X8)
91  else if(s->mb_intra)
93  else
95  }
96 }
97 
98 int ff_h263_pred_dc(MpegEncContext * s, int n, int16_t **dc_val_ptr)
99 {
100  int x, y, wrap, a, c, pred_dc;
101  int16_t *dc_val;
102 
103  /* find prediction */
104  if (n < 4) {
105  x = 2 * s->mb_x + (n & 1);
106  y = 2 * s->mb_y + ((n & 2) >> 1);
107  wrap = s->b8_stride;
108  dc_val = s->dc_val[0];
109  } else {
110  x = s->mb_x;
111  y = s->mb_y;
112  wrap = s->mb_stride;
113  dc_val = s->dc_val[n - 4 + 1];
114  }
115  /* B C
116  * A X
117  */
118  a = dc_val[(x - 1) + (y) * wrap];
119  c = dc_val[(x) + (y - 1) * wrap];
120 
121  /* No prediction outside GOB boundary */
122  if(s->first_slice_line && n!=3){
123  if(n!=2) c= 1024;
124  if(n!=1 && s->mb_x == s->resync_mb_x) a= 1024;
125  }
126  /* just DC prediction */
127  if (a != 1024 && c != 1024)
128  pred_dc = (a + c) >> 1;
129  else if (a != 1024)
130  pred_dc = a;
131  else
132  pred_dc = c;
133 
134  /* we assume pred is positive */
135  *dc_val_ptr = &dc_val[x + y * wrap];
136  return pred_dc;
137 }
138 
140  int qp_c;
141  const int linesize = s->linesize;
142  const int uvlinesize= s->uvlinesize;
143  const int xy = s->mb_y * s->mb_stride + s->mb_x;
144  uint8_t *dest_y = s->dest[0];
145  uint8_t *dest_cb= s->dest[1];
146  uint8_t *dest_cr= s->dest[2];
147 
148 // if(s->pict_type==AV_PICTURE_TYPE_B && !s->readable) return;
149 
150  /*
151  Diag Top
152  Left Center
153  */
154  if (!IS_SKIP(s->current_picture.mb_type[xy])) {
155  qp_c= s->qscale;
156  s->h263dsp.h263_v_loop_filter(dest_y + 8 * linesize, linesize, qp_c);
157  s->h263dsp.h263_v_loop_filter(dest_y + 8 * linesize + 8, linesize, qp_c);
158  }else
159  qp_c= 0;
160 
161  if(s->mb_y){
162  int qp_dt, qp_tt, qp_tc;
163 
164  if (IS_SKIP(s->current_picture.mb_type[xy - s->mb_stride]))
165  qp_tt=0;
166  else
167  qp_tt = s->current_picture.qscale_table[xy - s->mb_stride];
168 
169  if(qp_c)
170  qp_tc= qp_c;
171  else
172  qp_tc= qp_tt;
173 
174  if(qp_tc){
175  const int chroma_qp= s->chroma_qscale_table[qp_tc];
176  s->h263dsp.h263_v_loop_filter(dest_y, linesize, qp_tc);
177  s->h263dsp.h263_v_loop_filter(dest_y + 8, linesize, qp_tc);
178 
179  s->h263dsp.h263_v_loop_filter(dest_cb, uvlinesize, chroma_qp);
180  s->h263dsp.h263_v_loop_filter(dest_cr, uvlinesize, chroma_qp);
181  }
182 
183  if(qp_tt)
184  s->h263dsp.h263_h_loop_filter(dest_y - 8 * linesize + 8, linesize, qp_tt);
185 
186  if(s->mb_x){
187  if (qp_tt || IS_SKIP(s->current_picture.mb_type[xy - 1 - s->mb_stride]))
188  qp_dt= qp_tt;
189  else
190  qp_dt = s->current_picture.qscale_table[xy - 1 - s->mb_stride];
191 
192  if(qp_dt){
193  const int chroma_qp= s->chroma_qscale_table[qp_dt];
194  s->h263dsp.h263_h_loop_filter(dest_y - 8 * linesize, linesize, qp_dt);
195  s->h263dsp.h263_h_loop_filter(dest_cb - 8 * uvlinesize, uvlinesize, chroma_qp);
196  s->h263dsp.h263_h_loop_filter(dest_cr - 8 * uvlinesize, uvlinesize, chroma_qp);
197  }
198  }
199  }
200 
201  if(qp_c){
202  s->h263dsp.h263_h_loop_filter(dest_y + 8, linesize, qp_c);
203  if(s->mb_y + 1 == s->mb_height)
204  s->h263dsp.h263_h_loop_filter(dest_y + 8 * linesize + 8, linesize, qp_c);
205  }
206 
207  if(s->mb_x){
208  int qp_lc;
209  if (qp_c || IS_SKIP(s->current_picture.mb_type[xy - 1]))
210  qp_lc= qp_c;
211  else
212  qp_lc = s->current_picture.qscale_table[xy - 1];
213 
214  if(qp_lc){
215  s->h263dsp.h263_h_loop_filter(dest_y, linesize, qp_lc);
216  if(s->mb_y + 1 == s->mb_height){
217  const int chroma_qp= s->chroma_qscale_table[qp_lc];
218  s->h263dsp.h263_h_loop_filter(dest_y + 8 * linesize, linesize, qp_lc);
219  s->h263dsp.h263_h_loop_filter(dest_cb, uvlinesize, chroma_qp);
220  s->h263dsp.h263_h_loop_filter(dest_cr, uvlinesize, chroma_qp);
221  }
222  }
223  }
224 }
225 
226 void ff_h263_pred_acdc(MpegEncContext * s, int16_t *block, int n)
227 {
228  int x, y, wrap, a, c, pred_dc, scale, i;
229  int16_t *dc_val, *ac_val, *ac_val1;
230 
231  /* find prediction */
232  if (n < 4) {
233  x = 2 * s->mb_x + (n & 1);
234  y = 2 * s->mb_y + (n>> 1);
235  wrap = s->b8_stride;
236  dc_val = s->dc_val[0];
237  ac_val = s->ac_val[0][0];
238  scale = s->y_dc_scale;
239  } else {
240  x = s->mb_x;
241  y = s->mb_y;
242  wrap = s->mb_stride;
243  dc_val = s->dc_val[n - 4 + 1];
244  ac_val = s->ac_val[n - 4 + 1][0];
245  scale = s->c_dc_scale;
246  }
247 
248  ac_val += ((y) * wrap + (x)) * 16;
249  ac_val1 = ac_val;
250 
251  /* B C
252  * A X
253  */
254  a = dc_val[(x - 1) + (y) * wrap];
255  c = dc_val[(x) + (y - 1) * wrap];
256 
257  /* No prediction outside GOB boundary */
258  if(s->first_slice_line && n!=3){
259  if(n!=2) c= 1024;
260  if(n!=1 && s->mb_x == s->resync_mb_x) a= 1024;
261  }
262 
263  if (s->ac_pred) {
264  pred_dc = 1024;
265  if (s->h263_aic_dir) {
266  /* left prediction */
267  if (a != 1024) {
268  ac_val -= 16;
269  for(i=1;i<8;i++) {
270  block[s->idsp.idct_permutation[i << 3]] += ac_val[i];
271  }
272  pred_dc = a;
273  }
274  } else {
275  /* top prediction */
276  if (c != 1024) {
277  ac_val -= 16 * wrap;
278  for(i=1;i<8;i++) {
279  block[s->idsp.idct_permutation[i]] += ac_val[i + 8];
280  }
281  pred_dc = c;
282  }
283  }
284  } else {
285  /* just DC prediction */
286  if (a != 1024 && c != 1024)
287  pred_dc = (a + c) >> 1;
288  else if (a != 1024)
289  pred_dc = a;
290  else
291  pred_dc = c;
292  }
293 
294  /* we assume pred is positive */
295  block[0]=block[0]*scale + pred_dc;
296 
297  if (block[0] < 0)
298  block[0] = 0;
299  else
300  block[0] |= 1;
301 
302  /* Update AC/DC tables */
303  dc_val[(x) + (y) * wrap] = block[0];
304 
305  /* left copy */
306  for(i=1;i<8;i++)
307  ac_val1[i] = block[s->idsp.idct_permutation[i << 3]];
308  /* top copy */
309  for(i=1;i<8;i++)
310  ac_val1[8 + i] = block[s->idsp.idct_permutation[i]];
311 }
312 
313 int16_t *ff_h263_pred_motion(MpegEncContext * s, int block, int dir,
314  int *px, int *py)
315 {
316  int wrap;
317  int16_t *A, *B, *C, (*mot_val)[2];
318  static const int off[4]= {2, 1, 1, -1};
319 
320  wrap = s->b8_stride;
321  mot_val = s->current_picture.motion_val[dir] + s->block_index[block];
322 
323  A = mot_val[ - 1];
324  /* special case for first (slice) line */
325  if (s->first_slice_line && block<3) {
326  // we can't just change some MVs to simulate that as we need them for the B frames (and ME)
327  // and if we ever support non rectangular objects than we need to do a few ifs here anyway :(
328  if(block==0){ //most common case
329  if(s->mb_x == s->resync_mb_x){ //rare
330  *px= *py = 0;
331  }else if(s->mb_x + 1 == s->resync_mb_x && s->h263_pred){ //rare
332  C = mot_val[off[block] - wrap];
333  if(s->mb_x==0){
334  *px = C[0];
335  *py = C[1];
336  }else{
337  *px = mid_pred(A[0], 0, C[0]);
338  *py = mid_pred(A[1], 0, C[1]);
339  }
340  }else{
341  *px = A[0];
342  *py = A[1];
343  }
344  }else if(block==1){
345  if(s->mb_x + 1 == s->resync_mb_x && s->h263_pred){ //rare
346  C = mot_val[off[block] - wrap];
347  *px = mid_pred(A[0], 0, C[0]);
348  *py = mid_pred(A[1], 0, C[1]);
349  }else{
350  *px = A[0];
351  *py = A[1];
352  }
353  }else{ /* block==2*/
354  B = mot_val[ - wrap];
355  C = mot_val[off[block] - wrap];
356  if(s->mb_x == s->resync_mb_x) //rare
357  A[0]=A[1]=0;
358 
359  *px = mid_pred(A[0], B[0], C[0]);
360  *py = mid_pred(A[1], B[1], C[1]);
361  }
362  } else {
363  B = mot_val[ - wrap];
364  C = mot_val[off[block] - wrap];
365  *px = mid_pred(A[0], B[0], C[0]);
366  *py = mid_pred(A[1], B[1], C[1]);
367  }
368  return *mot_val;
369 }