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rv40.c
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1 /*
2  * RV40 decoder
3  * Copyright (c) 2007 Konstantin Shishkov
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * RV40 decoder
25  */
26 
27 #include "libavutil/imgutils.h"
28 
29 #include "avcodec.h"
30 #include "dsputil.h"
31 #include "mpegvideo.h"
32 #include "golomb.h"
33 
34 #include "rv34.h"
35 #include "rv40vlc2.h"
36 #include "rv40data.h"
37 
41 
42 static const int16_t mode2_offs[] = {
43  0, 614, 1222, 1794, 2410, 3014, 3586, 4202, 4792, 5382, 5966, 6542,
44  7138, 7716, 8292, 8864, 9444, 10030, 10642, 11212, 11814
45 };
46 
47 /**
48  * Initialize all tables.
49  */
50 static av_cold void rv40_init_tables(void)
51 {
52  int i;
53  static VLC_TYPE aic_table[1 << AIC_TOP_BITS][2];
54  static VLC_TYPE aic_mode1_table[AIC_MODE1_NUM << AIC_MODE1_BITS][2];
55  static VLC_TYPE aic_mode2_table[11814][2];
56  static VLC_TYPE ptype_table[NUM_PTYPE_VLCS << PTYPE_VLC_BITS][2];
57  static VLC_TYPE btype_table[NUM_BTYPE_VLCS << BTYPE_VLC_BITS][2];
58 
59  aic_top_vlc.table = aic_table;
60  aic_top_vlc.table_allocated = 1 << AIC_TOP_BITS;
61  init_vlc(&aic_top_vlc, AIC_TOP_BITS, AIC_TOP_SIZE,
64  for(i = 0; i < AIC_MODE1_NUM; i++){
65  // Every tenth VLC table is empty
66  if((i % 10) == 9) continue;
67  aic_mode1_vlc[i].table = &aic_mode1_table[i << AIC_MODE1_BITS];
68  aic_mode1_vlc[i].table_allocated = 1 << AIC_MODE1_BITS;
69  init_vlc(&aic_mode1_vlc[i], AIC_MODE1_BITS, AIC_MODE1_SIZE,
70  aic_mode1_vlc_bits[i], 1, 1,
72  }
73  for(i = 0; i < AIC_MODE2_NUM; i++){
74  aic_mode2_vlc[i].table = &aic_mode2_table[mode2_offs[i]];
75  aic_mode2_vlc[i].table_allocated = mode2_offs[i + 1] - mode2_offs[i];
76  init_vlc(&aic_mode2_vlc[i], AIC_MODE2_BITS, AIC_MODE2_SIZE,
77  aic_mode2_vlc_bits[i], 1, 1,
79  }
80  for(i = 0; i < NUM_PTYPE_VLCS; i++){
81  ptype_vlc[i].table = &ptype_table[i << PTYPE_VLC_BITS];
82  ptype_vlc[i].table_allocated = 1 << PTYPE_VLC_BITS;
84  ptype_vlc_bits[i], 1, 1,
85  ptype_vlc_codes[i], 1, 1,
87  }
88  for(i = 0; i < NUM_BTYPE_VLCS; i++){
89  btype_vlc[i].table = &btype_table[i << BTYPE_VLC_BITS];
90  btype_vlc[i].table_allocated = 1 << BTYPE_VLC_BITS;
92  btype_vlc_bits[i], 1, 1,
93  btype_vlc_codes[i], 1, 1,
95  }
96 }
97 
98 /**
99  * Get stored dimension from bitstream.
100  *
101  * If the width/height is the standard one then it's coded as a 3-bit index.
102  * Otherwise it is coded as escaped 8-bit portions.
103  */
104 static int get_dimension(GetBitContext *gb, const int *dim)
105 {
106  int t = get_bits(gb, 3);
107  int val = dim[t];
108  if(val < 0)
109  val = dim[get_bits1(gb) - val];
110  if(!val){
111  do{
112  t = get_bits(gb, 8);
113  val += t << 2;
114  }while(t == 0xFF);
115  }
116  return val;
117 }
118 
119 /**
120  * Get encoded picture size - usually this is called from rv40_parse_slice_header.
121  */
122 static void rv40_parse_picture_size(GetBitContext *gb, int *w, int *h)
123 {
126 }
127 
129 {
130  int mb_bits;
131  int w = r->s.width, h = r->s.height;
132  int mb_size;
133 
134  memset(si, 0, sizeof(SliceInfo));
135  if(get_bits1(gb))
136  return -1;
137  si->type = get_bits(gb, 2);
138  if(si->type == 1) si->type = 0;
139  si->quant = get_bits(gb, 5);
140  if(get_bits(gb, 2))
141  return -1;
142  si->vlc_set = get_bits(gb, 2);
143  skip_bits1(gb);
144  si->pts = get_bits(gb, 13);
145  if(!si->type || !get_bits1(gb))
146  rv40_parse_picture_size(gb, &w, &h);
147  if(av_image_check_size(w, h, 0, r->s.avctx) < 0)
148  return -1;
149  si->width = w;
150  si->height = h;
151  mb_size = ((w + 15) >> 4) * ((h + 15) >> 4);
152  mb_bits = ff_rv34_get_start_offset(gb, mb_size);
153  si->start = get_bits(gb, mb_bits);
154 
155  return 0;
156 }
157 
158 /**
159  * Decode 4x4 intra types array.
160  */
162 {
163  MpegEncContext *s = &r->s;
164  int i, j, k, v;
165  int A, B, C;
166  int pattern;
167  int8_t *ptr;
168 
169  for(i = 0; i < 4; i++, dst += r->intra_types_stride){
170  if(!i && s->first_slice_line){
171  pattern = get_vlc2(gb, aic_top_vlc.table, AIC_TOP_BITS, 1);
172  dst[0] = (pattern >> 2) & 2;
173  dst[1] = (pattern >> 1) & 2;
174  dst[2] = pattern & 2;
175  dst[3] = (pattern << 1) & 2;
176  continue;
177  }
178  ptr = dst;
179  for(j = 0; j < 4; j++){
180  /* Coefficients are read using VLC chosen by the prediction pattern
181  * The first one (used for retrieving a pair of coefficients) is
182  * constructed from the top, top right and left coefficients
183  * The second one (used for retrieving only one coefficient) is
184  * top + 10 * left.
185  */
186  A = ptr[-r->intra_types_stride + 1]; // it won't be used for the last coefficient in a row
187  B = ptr[-r->intra_types_stride];
188  C = ptr[-1];
189  pattern = A + (B << 4) + (C << 8);
190  for(k = 0; k < MODE2_PATTERNS_NUM; k++)
191  if(pattern == rv40_aic_table_index[k])
192  break;
193  if(j < 3 && k < MODE2_PATTERNS_NUM){ //pattern is found, decoding 2 coefficients
194  v = get_vlc2(gb, aic_mode2_vlc[k].table, AIC_MODE2_BITS, 2);
195  *ptr++ = v/9;
196  *ptr++ = v%9;
197  j++;
198  }else{
199  if(B != -1 && C != -1)
200  v = get_vlc2(gb, aic_mode1_vlc[B + C*10].table, AIC_MODE1_BITS, 1);
201  else{ // tricky decoding
202  v = 0;
203  switch(C){
204  case -1: // code 0 -> 1, 1 -> 0
205  if(B < 2)
206  v = get_bits1(gb) ^ 1;
207  break;
208  case 0:
209  case 2: // code 0 -> 2, 1 -> 0
210  v = (get_bits1(gb) ^ 1) << 1;
211  break;
212  }
213  }
214  *ptr++ = v;
215  }
216  }
217  }
218  return 0;
219 }
220 
221 /**
222  * Decode macroblock information.
223  */
225 {
226  MpegEncContext *s = &r->s;
227  GetBitContext *gb = &s->gb;
228  int q, i;
229  int prev_type = 0;
230  int mb_pos = s->mb_x + s->mb_y * s->mb_stride;
231 
232  if(!r->s.mb_skip_run) {
233  r->s.mb_skip_run = svq3_get_ue_golomb(gb) + 1;
234  if(r->s.mb_skip_run > (unsigned)s->mb_num)
235  return -1;
236  }
237 
238  if(--r->s.mb_skip_run)
239  return RV34_MB_SKIP;
240 
241  if(r->avail_cache[6-4]){
242  int blocks[RV34_MB_TYPES] = {0};
243  int count = 0;
244  if(r->avail_cache[6-1])
245  blocks[r->mb_type[mb_pos - 1]]++;
246  blocks[r->mb_type[mb_pos - s->mb_stride]]++;
247  if(r->avail_cache[6-2])
248  blocks[r->mb_type[mb_pos - s->mb_stride + 1]]++;
249  if(r->avail_cache[6-5])
250  blocks[r->mb_type[mb_pos - s->mb_stride - 1]]++;
251  for(i = 0; i < RV34_MB_TYPES; i++){
252  if(blocks[i] > count){
253  count = blocks[i];
254  prev_type = i;
255  if(count>1)
256  break;
257  }
258  }
259  } else if (r->avail_cache[6-1])
260  prev_type = r->mb_type[mb_pos - 1];
261 
262  if(s->pict_type == AV_PICTURE_TYPE_P){
263  prev_type = block_num_to_ptype_vlc_num[prev_type];
264  q = get_vlc2(gb, ptype_vlc[prev_type].table, PTYPE_VLC_BITS, 1);
265  if(q < PBTYPE_ESCAPE)
266  return q;
267  q = get_vlc2(gb, ptype_vlc[prev_type].table, PTYPE_VLC_BITS, 1);
268  av_log(s->avctx, AV_LOG_ERROR, "Dquant for P-frame\n");
269  }else{
270  prev_type = block_num_to_btype_vlc_num[prev_type];
271  q = get_vlc2(gb, btype_vlc[prev_type].table, BTYPE_VLC_BITS, 1);
272  if(q < PBTYPE_ESCAPE)
273  return q;
274  q = get_vlc2(gb, btype_vlc[prev_type].table, BTYPE_VLC_BITS, 1);
275  av_log(s->avctx, AV_LOG_ERROR, "Dquant for B-frame\n");
276  }
277  return 0;
278 }
279 
285 };
286 
287 #define MASK_CUR 0x0001
288 #define MASK_RIGHT 0x0008
289 #define MASK_BOTTOM 0x0010
290 #define MASK_TOP 0x1000
291 #define MASK_Y_TOP_ROW 0x000F
292 #define MASK_Y_LAST_ROW 0xF000
293 #define MASK_Y_LEFT_COL 0x1111
294 #define MASK_Y_RIGHT_COL 0x8888
295 #define MASK_C_TOP_ROW 0x0003
296 #define MASK_C_LAST_ROW 0x000C
297 #define MASK_C_LEFT_COL 0x0005
298 #define MASK_C_RIGHT_COL 0x000A
299 
300 static const int neighbour_offs_x[4] = { 0, 0, -1, 0 };
301 static const int neighbour_offs_y[4] = { 0, -1, 0, 1 };
302 
304  uint8_t *src, int stride, int dmode,
305  int lim_q1, int lim_p1,
306  int alpha, int beta, int beta2,
307  int chroma, int edge, int dir)
308 {
309  int filter_p1, filter_q1;
310  int strong;
311  int lims;
312 
313  strong = rdsp->rv40_loop_filter_strength[dir](src, stride, beta, beta2,
314  edge, &filter_p1, &filter_q1);
315 
316  lims = filter_p1 + filter_q1 + ((lim_q1 + lim_p1) >> 1) + 1;
317 
318  if (strong) {
319  rdsp->rv40_strong_loop_filter[dir](src, stride, alpha,
320  lims, dmode, chroma);
321  } else if (filter_p1 & filter_q1) {
322  rdsp->rv40_weak_loop_filter[dir](src, stride, 1, 1, alpha, beta,
323  lims, lim_q1, lim_p1);
324  } else if (filter_p1 | filter_q1) {
325  rdsp->rv40_weak_loop_filter[dir](src, stride, filter_p1, filter_q1,
326  alpha, beta, lims >> 1, lim_q1 >> 1,
327  lim_p1 >> 1);
328  }
329 }
330 
331 /**
332  * RV40 loop filtering function
333  */
334 static void rv40_loop_filter(RV34DecContext *r, int row)
335 {
336  MpegEncContext *s = &r->s;
337  int mb_pos, mb_x;
338  int i, j, k;
339  uint8_t *Y, *C;
340  int alpha, beta, betaY, betaC;
341  int q;
342  int mbtype[4]; ///< current macroblock and its neighbours types
343  /**
344  * flags indicating that macroblock can be filtered with strong filter
345  * it is set only for intra coded MB and MB with DCs coded separately
346  */
347  int mb_strong[4];
348  int clip[4]; ///< MB filter clipping value calculated from filtering strength
349  /**
350  * coded block patterns for luma part of current macroblock and its neighbours
351  * Format:
352  * LSB corresponds to the top left block,
353  * each nibble represents one row of subblocks.
354  */
355  int cbp[4];
356  /**
357  * coded block patterns for chroma part of current macroblock and its neighbours
358  * Format is the same as for luma with two subblocks in a row.
359  */
360  int uvcbp[4][2];
361  /**
362  * This mask represents the pattern of luma subblocks that should be filtered
363  * in addition to the coded ones because because they lie at the edge of
364  * 8x8 block with different enough motion vectors
365  */
366  unsigned mvmasks[4];
367 
368  mb_pos = row * s->mb_stride;
369  for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){
370  int mbtype = s->current_picture_ptr->f.mb_type[mb_pos];
371  if(IS_INTRA(mbtype) || IS_SEPARATE_DC(mbtype))
372  r->cbp_luma [mb_pos] = r->deblock_coefs[mb_pos] = 0xFFFF;
373  if(IS_INTRA(mbtype))
374  r->cbp_chroma[mb_pos] = 0xFF;
375  }
376  mb_pos = row * s->mb_stride;
377  for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){
378  int y_h_deblock, y_v_deblock;
379  int c_v_deblock[2], c_h_deblock[2];
380  int clip_left;
381  int avail[4];
382  unsigned y_to_deblock;
383  int c_to_deblock[2];
384 
385  q = s->current_picture_ptr->f.qscale_table[mb_pos];
386  alpha = rv40_alpha_tab[q];
387  beta = rv40_beta_tab [q];
388  betaY = betaC = beta * 3;
389  if(s->width * s->height <= 176*144)
390  betaY += beta;
391 
392  avail[0] = 1;
393  avail[1] = row;
394  avail[2] = mb_x;
395  avail[3] = row < s->mb_height - 1;
396  for(i = 0; i < 4; i++){
397  if(avail[i]){
398  int pos = mb_pos + neighbour_offs_x[i] + neighbour_offs_y[i]*s->mb_stride;
399  mvmasks[i] = r->deblock_coefs[pos];
400  mbtype [i] = s->current_picture_ptr->f.mb_type[pos];
401  cbp [i] = r->cbp_luma[pos];
402  uvcbp[i][0] = r->cbp_chroma[pos] & 0xF;
403  uvcbp[i][1] = r->cbp_chroma[pos] >> 4;
404  }else{
405  mvmasks[i] = 0;
406  mbtype [i] = mbtype[0];
407  cbp [i] = 0;
408  uvcbp[i][0] = uvcbp[i][1] = 0;
409  }
410  mb_strong[i] = IS_INTRA(mbtype[i]) || IS_SEPARATE_DC(mbtype[i]);
411  clip[i] = rv40_filter_clip_tbl[mb_strong[i] + 1][q];
412  }
413  y_to_deblock = mvmasks[POS_CUR]
414  | (mvmasks[POS_BOTTOM] << 16);
415  /* This pattern contains bits signalling that horizontal edges of
416  * the current block can be filtered.
417  * That happens when either of adjacent subblocks is coded or lies on
418  * the edge of 8x8 blocks with motion vectors differing by more than
419  * 3/4 pel in any component (any edge orientation for some reason).
420  */
421  y_h_deblock = y_to_deblock
422  | ((cbp[POS_CUR] << 4) & ~MASK_Y_TOP_ROW)
423  | ((cbp[POS_TOP] & MASK_Y_LAST_ROW) >> 12);
424  /* This pattern contains bits signalling that vertical edges of
425  * the current block can be filtered.
426  * That happens when either of adjacent subblocks is coded or lies on
427  * the edge of 8x8 blocks with motion vectors differing by more than
428  * 3/4 pel in any component (any edge orientation for some reason).
429  */
430  y_v_deblock = y_to_deblock
431  | ((cbp[POS_CUR] << 1) & ~MASK_Y_LEFT_COL)
432  | ((cbp[POS_LEFT] & MASK_Y_RIGHT_COL) >> 3);
433  if(!mb_x)
434  y_v_deblock &= ~MASK_Y_LEFT_COL;
435  if(!row)
436  y_h_deblock &= ~MASK_Y_TOP_ROW;
437  if(row == s->mb_height - 1 || (mb_strong[POS_CUR] | mb_strong[POS_BOTTOM]))
438  y_h_deblock &= ~(MASK_Y_TOP_ROW << 16);
439  /* Calculating chroma patterns is similar and easier since there is
440  * no motion vector pattern for them.
441  */
442  for(i = 0; i < 2; i++){
443  c_to_deblock[i] = (uvcbp[POS_BOTTOM][i] << 4) | uvcbp[POS_CUR][i];
444  c_v_deblock[i] = c_to_deblock[i]
445  | ((uvcbp[POS_CUR] [i] << 1) & ~MASK_C_LEFT_COL)
446  | ((uvcbp[POS_LEFT][i] & MASK_C_RIGHT_COL) >> 1);
447  c_h_deblock[i] = c_to_deblock[i]
448  | ((uvcbp[POS_TOP][i] & MASK_C_LAST_ROW) >> 2)
449  | (uvcbp[POS_CUR][i] << 2);
450  if(!mb_x)
451  c_v_deblock[i] &= ~MASK_C_LEFT_COL;
452  if(!row)
453  c_h_deblock[i] &= ~MASK_C_TOP_ROW;
454  if(row == s->mb_height - 1 || (mb_strong[POS_CUR] | mb_strong[POS_BOTTOM]))
455  c_h_deblock[i] &= ~(MASK_C_TOP_ROW << 4);
456  }
457 
458  for(j = 0; j < 16; j += 4){
459  Y = s->current_picture_ptr->f.data[0] + mb_x*16 + (row*16 + j) * s->linesize;
460  for(i = 0; i < 4; i++, Y += 4){
461  int ij = i + j;
462  int clip_cur = y_to_deblock & (MASK_CUR << ij) ? clip[POS_CUR] : 0;
463  int dither = j ? ij : i*4;
464 
465  // if bottom block is coded then we can filter its top edge
466  // (or bottom edge of this block, which is the same)
467  if(y_h_deblock & (MASK_BOTTOM << ij)){
469  s->linesize, dither,
470  y_to_deblock & (MASK_BOTTOM << ij) ? clip[POS_CUR] : 0,
471  clip_cur, alpha, beta, betaY,
472  0, 0, 0);
473  }
474  // filter left block edge in ordinary mode (with low filtering strength)
475  if(y_v_deblock & (MASK_CUR << ij) && (i || !(mb_strong[POS_CUR] | mb_strong[POS_LEFT]))){
476  if(!i)
477  clip_left = mvmasks[POS_LEFT] & (MASK_RIGHT << j) ? clip[POS_LEFT] : 0;
478  else
479  clip_left = y_to_deblock & (MASK_CUR << (ij-1)) ? clip[POS_CUR] : 0;
480  rv40_adaptive_loop_filter(&r->rdsp, Y, s->linesize, dither,
481  clip_cur,
482  clip_left,
483  alpha, beta, betaY, 0, 0, 1);
484  }
485  // filter top edge of the current macroblock when filtering strength is high
486  if(!j && y_h_deblock & (MASK_CUR << i) && (mb_strong[POS_CUR] | mb_strong[POS_TOP])){
487  rv40_adaptive_loop_filter(&r->rdsp, Y, s->linesize, dither,
488  clip_cur,
489  mvmasks[POS_TOP] & (MASK_TOP << i) ? clip[POS_TOP] : 0,
490  alpha, beta, betaY, 0, 1, 0);
491  }
492  // filter left block edge in edge mode (with high filtering strength)
493  if(y_v_deblock & (MASK_CUR << ij) && !i && (mb_strong[POS_CUR] | mb_strong[POS_LEFT])){
494  clip_left = mvmasks[POS_LEFT] & (MASK_RIGHT << j) ? clip[POS_LEFT] : 0;
495  rv40_adaptive_loop_filter(&r->rdsp, Y, s->linesize, dither,
496  clip_cur,
497  clip_left,
498  alpha, beta, betaY, 0, 1, 1);
499  }
500  }
501  }
502  for(k = 0; k < 2; k++){
503  for(j = 0; j < 2; j++){
504  C = s->current_picture_ptr->f.data[k + 1] + mb_x*8 + (row*8 + j*4) * s->uvlinesize;
505  for(i = 0; i < 2; i++, C += 4){
506  int ij = i + j*2;
507  int clip_cur = c_to_deblock[k] & (MASK_CUR << ij) ? clip[POS_CUR] : 0;
508  if(c_h_deblock[k] & (MASK_CUR << (ij+2))){
509  int clip_bot = c_to_deblock[k] & (MASK_CUR << (ij+2)) ? clip[POS_CUR] : 0;
511  clip_bot,
512  clip_cur,
513  alpha, beta, betaC, 1, 0, 0);
514  }
515  if((c_v_deblock[k] & (MASK_CUR << ij)) && (i || !(mb_strong[POS_CUR] | mb_strong[POS_LEFT]))){
516  if(!i)
517  clip_left = uvcbp[POS_LEFT][k] & (MASK_CUR << (2*j+1)) ? clip[POS_LEFT] : 0;
518  else
519  clip_left = c_to_deblock[k] & (MASK_CUR << (ij-1)) ? clip[POS_CUR] : 0;
520  rv40_adaptive_loop_filter(&r->rdsp, C, s->uvlinesize, j*8,
521  clip_cur,
522  clip_left,
523  alpha, beta, betaC, 1, 0, 1);
524  }
525  if(!j && c_h_deblock[k] & (MASK_CUR << ij) && (mb_strong[POS_CUR] | mb_strong[POS_TOP])){
526  int clip_top = uvcbp[POS_TOP][k] & (MASK_CUR << (ij+2)) ? clip[POS_TOP] : 0;
527  rv40_adaptive_loop_filter(&r->rdsp, C, s->uvlinesize, i*8,
528  clip_cur,
529  clip_top,
530  alpha, beta, betaC, 1, 1, 0);
531  }
532  if(c_v_deblock[k] & (MASK_CUR << ij) && !i && (mb_strong[POS_CUR] | mb_strong[POS_LEFT])){
533  clip_left = uvcbp[POS_LEFT][k] & (MASK_CUR << (2*j+1)) ? clip[POS_LEFT] : 0;
534  rv40_adaptive_loop_filter(&r->rdsp, C, s->uvlinesize, j*8,
535  clip_cur,
536  clip_left,
537  alpha, beta, betaC, 1, 1, 1);
538  }
539  }
540  }
541  }
542  }
543 }
544 
545 /**
546  * Initialize decoder.
547  */
549 {
550  RV34DecContext *r = avctx->priv_data;
551 
552  r->rv30 = 0;
553  ff_rv34_decode_init(avctx);
554  if(!aic_top_vlc.bits)
562  return 0;
563 }
564 
566  .name = "rv40",
567  .type = AVMEDIA_TYPE_VIDEO,
568  .id = AV_CODEC_ID_RV40,
569  .priv_data_size = sizeof(RV34DecContext),
573  .capabilities = CODEC_CAP_DR1 | CODEC_CAP_DELAY |
575  .flush = ff_mpeg_flush,
576  .long_name = NULL_IF_CONFIG_SMALL("RealVideo 4.0"),
577  .pix_fmts = ff_pixfmt_list_420,
580 };