1/** 2 * @file libavcodec/vp6.c 3 * VP6 compatible video decoder 4 * 5 * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org> 6 * 7 * The VP6F decoder accepts an optional 1 byte extradata. It is composed of: 8 * - upper 4bits: difference between encoded width and visible width 9 * - lower 4bits: difference between encoded height and visible height 10 * 11 * This file is part of FFmpeg. 12 * 13 * FFmpeg is free software; you can redistribute it and/or 14 * modify it under the terms of the GNU Lesser General Public 15 * License as published by the Free Software Foundation; either 16 * version 2.1 of the License, or (at your option) any later version. 17 * 18 * FFmpeg is distributed in the hope that it will be useful, 19 * but WITHOUT ANY WARRANTY; without even the implied warranty of 20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 21 * Lesser General Public License for more details. 22 * 23 * You should have received a copy of the GNU Lesser General Public 24 * License along with FFmpeg; if not, write to the Free Software 25 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 26 */ 27 28#include <stdlib.h> 29 30#include "avcodec.h" 31#include "dsputil.h" 32#include "bitstream.h" 33#include "huffman.h" 34 35#include "vp56.h" 36#include "vp56data.h" 37#include "vp6data.h" 38 39 40static void vp6_parse_coeff(VP56Context *s); 41static void vp6_parse_coeff_huffman(VP56Context *s); 42 43static int vp6_parse_header(VP56Context *s, const uint8_t *buf, int buf_size, 44 int *golden_frame) 45{ 46 VP56RangeCoder *c = &s->c; 47 int parse_filter_info = 0; 48 int coeff_offset = 0; 49 int vrt_shift = 0; 50 int sub_version; 51 int rows, cols; 52 int res = 1; 53 int separated_coeff = buf[0] & 1; 54 55 s->framep[VP56_FRAME_CURRENT]->key_frame = !(buf[0] & 0x80); 56 vp56_init_dequant(s, (buf[0] >> 1) & 0x3F); 57 58 if (s->framep[VP56_FRAME_CURRENT]->key_frame) { 59 sub_version = buf[1] >> 3; 60 if (sub_version > 8) 61 return 0; 62 s->filter_header = buf[1] & 0x06; 63 if (buf[1] & 1) { 64 av_log(s->avctx, AV_LOG_ERROR, "interlacing not supported\n"); 65 return 0; 66 } 67 if (separated_coeff || !s->filter_header) { 68 coeff_offset = AV_RB16(buf+2) - 2; 69 buf += 2; 70 buf_size -= 2; 71 } 72 73 rows = buf[2]; /* number of stored macroblock rows */ 74 cols = buf[3]; /* number of stored macroblock cols */ 75 /* buf[4] is number of displayed macroblock rows */ 76 /* buf[5] is number of displayed macroblock cols */ 77 78 if (!s->macroblocks || /* first frame */ 79 16*cols != s->avctx->coded_width || 80 16*rows != s->avctx->coded_height) { 81 avcodec_set_dimensions(s->avctx, 16*cols, 16*rows); 82 if (s->avctx->extradata_size == 1) { 83 s->avctx->width -= s->avctx->extradata[0] >> 4; 84 s->avctx->height -= s->avctx->extradata[0] & 0x0F; 85 } 86 res = 2; 87 } 88 89 vp56_init_range_decoder(c, buf+6, buf_size-6); 90 vp56_rac_gets(c, 2); 91 92 parse_filter_info = s->filter_header; 93 if (sub_version < 8) 94 vrt_shift = 5; 95 s->sub_version = sub_version; 96 } else { 97 if (!s->sub_version) 98 return 0; 99 100 if (separated_coeff || !s->filter_header) { 101 coeff_offset = AV_RB16(buf+1) - 2; 102 buf += 2; 103 buf_size -= 2; 104 } 105 vp56_init_range_decoder(c, buf+1, buf_size-1); 106 107 *golden_frame = vp56_rac_get(c); 108 if (s->filter_header) { 109 s->deblock_filtering = vp56_rac_get(c); 110 if (s->deblock_filtering) 111 vp56_rac_get(c); 112 if (s->sub_version > 7) 113 parse_filter_info = vp56_rac_get(c); 114 } 115 } 116 117 if (parse_filter_info) { 118 if (vp56_rac_get(c)) { 119 s->filter_mode = 2; 120 s->sample_variance_threshold = vp56_rac_gets(c, 5) << vrt_shift; 121 s->max_vector_length = 2 << vp56_rac_gets(c, 3); 122 } else if (vp56_rac_get(c)) { 123 s->filter_mode = 1; 124 } else { 125 s->filter_mode = 0; 126 } 127 if (s->sub_version > 7) 128 s->filter_selection = vp56_rac_gets(c, 4); 129 else 130 s->filter_selection = 16; 131 } 132 133 s->use_huffman = vp56_rac_get(c); 134 135 s->parse_coeff = vp6_parse_coeff; 136 if (coeff_offset) { 137 buf += coeff_offset; 138 buf_size -= coeff_offset; 139 if (buf_size < 0) 140 return 0; 141 if (s->use_huffman) { 142 s->parse_coeff = vp6_parse_coeff_huffman; 143 init_get_bits(&s->gb, buf, buf_size<<3); 144 } else { 145 vp56_init_range_decoder(&s->cc, buf, buf_size); 146 s->ccp = &s->cc; 147 } 148 } else { 149 s->ccp = &s->c; 150 } 151 152 return res; 153} 154 155static void vp6_coeff_order_table_init(VP56Context *s) 156{ 157 int i, pos, idx = 1; 158 159 s->modelp->coeff_index_to_pos[0] = 0; 160 for (i=0; i<16; i++) 161 for (pos=1; pos<64; pos++) 162 if (s->modelp->coeff_reorder[pos] == i) 163 s->modelp->coeff_index_to_pos[idx++] = pos; 164} 165 166static void vp6_default_models_init(VP56Context *s) 167{ 168 VP56Model *model = s->modelp; 169 170 model->vector_dct[0] = 0xA2; 171 model->vector_dct[1] = 0xA4; 172 model->vector_sig[0] = 0x80; 173 model->vector_sig[1] = 0x80; 174 175 memcpy(model->mb_types_stats, vp56_def_mb_types_stats, sizeof(model->mb_types_stats)); 176 memcpy(model->vector_fdv, vp6_def_fdv_vector_model, sizeof(model->vector_fdv)); 177 memcpy(model->vector_pdv, vp6_def_pdv_vector_model, sizeof(model->vector_pdv)); 178 memcpy(model->coeff_runv, vp6_def_runv_coeff_model, sizeof(model->coeff_runv)); 179 memcpy(model->coeff_reorder, vp6_def_coeff_reorder, sizeof(model->coeff_reorder)); 180 181 vp6_coeff_order_table_init(s); 182} 183 184static void vp6_parse_vector_models(VP56Context *s) 185{ 186 VP56RangeCoder *c = &s->c; 187 VP56Model *model = s->modelp; 188 int comp, node; 189 190 for (comp=0; comp<2; comp++) { 191 if (vp56_rac_get_prob(c, vp6_sig_dct_pct[comp][0])) 192 model->vector_dct[comp] = vp56_rac_gets_nn(c, 7); 193 if (vp56_rac_get_prob(c, vp6_sig_dct_pct[comp][1])) 194 model->vector_sig[comp] = vp56_rac_gets_nn(c, 7); 195 } 196 197 for (comp=0; comp<2; comp++) 198 for (node=0; node<7; node++) 199 if (vp56_rac_get_prob(c, vp6_pdv_pct[comp][node])) 200 model->vector_pdv[comp][node] = vp56_rac_gets_nn(c, 7); 201 202 for (comp=0; comp<2; comp++) 203 for (node=0; node<8; node++) 204 if (vp56_rac_get_prob(c, vp6_fdv_pct[comp][node])) 205 model->vector_fdv[comp][node] = vp56_rac_gets_nn(c, 7); 206} 207 208/* nodes must ascend by count, but with descending symbol order */ 209static int vp6_huff_cmp(const void *va, const void *vb) 210{ 211 const Node *a = va, *b = vb; 212 return (a->count - b->count)*16 + (b->sym - a->sym); 213} 214 215static void vp6_build_huff_tree(VP56Context *s, uint8_t coeff_model[], 216 const uint8_t *map, unsigned size, VLC *vlc) 217{ 218 Node nodes[2*size], *tmp = &nodes[size]; 219 int a, b, i; 220 221 /* first compute probabilities from model */ 222 tmp[0].count = 256; 223 for (i=0; i<size-1; i++) { 224 a = tmp[i].count * coeff_model[i] >> 8; 225 b = tmp[i].count * (255 - coeff_model[i]) >> 8; 226 nodes[map[2*i ]].count = a + !a; 227 nodes[map[2*i+1]].count = b + !b; 228 } 229 230 /* then build the huffman tree accodring to probabilities */ 231 ff_huff_build_tree(s->avctx, vlc, size, nodes, vp6_huff_cmp, 232 FF_HUFFMAN_FLAG_HNODE_FIRST); 233} 234 235static void vp6_parse_coeff_models(VP56Context *s) 236{ 237 VP56RangeCoder *c = &s->c; 238 VP56Model *model = s->modelp; 239 int def_prob[11]; 240 int node, cg, ctx, pos; 241 int ct; /* code type */ 242 int pt; /* plane type (0 for Y, 1 for U or V) */ 243 244 memset(def_prob, 0x80, sizeof(def_prob)); 245 246 for (pt=0; pt<2; pt++) 247 for (node=0; node<11; node++) 248 if (vp56_rac_get_prob(c, vp6_dccv_pct[pt][node])) { 249 def_prob[node] = vp56_rac_gets_nn(c, 7); 250 model->coeff_dccv[pt][node] = def_prob[node]; 251 } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) { 252 model->coeff_dccv[pt][node] = def_prob[node]; 253 } 254 255 if (vp56_rac_get(c)) { 256 for (pos=1; pos<64; pos++) 257 if (vp56_rac_get_prob(c, vp6_coeff_reorder_pct[pos])) 258 model->coeff_reorder[pos] = vp56_rac_gets(c, 4); 259 vp6_coeff_order_table_init(s); 260 } 261 262 for (cg=0; cg<2; cg++) 263 for (node=0; node<14; node++) 264 if (vp56_rac_get_prob(c, vp6_runv_pct[cg][node])) 265 model->coeff_runv[cg][node] = vp56_rac_gets_nn(c, 7); 266 267 for (ct=0; ct<3; ct++) 268 for (pt=0; pt<2; pt++) 269 for (cg=0; cg<6; cg++) 270 for (node=0; node<11; node++) 271 if (vp56_rac_get_prob(c, vp6_ract_pct[ct][pt][cg][node])) { 272 def_prob[node] = vp56_rac_gets_nn(c, 7); 273 model->coeff_ract[pt][ct][cg][node] = def_prob[node]; 274 } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) { 275 model->coeff_ract[pt][ct][cg][node] = def_prob[node]; 276 } 277 278 if (s->use_huffman) { 279 for (pt=0; pt<2; pt++) { 280 vp6_build_huff_tree(s, model->coeff_dccv[pt], 281 vp6_huff_coeff_map, 12, &s->dccv_vlc[pt]); 282 vp6_build_huff_tree(s, model->coeff_runv[pt], 283 vp6_huff_run_map, 9, &s->runv_vlc[pt]); 284 for (ct=0; ct<3; ct++) 285 for (cg = 0; cg < 6; cg++) 286 vp6_build_huff_tree(s, model->coeff_ract[pt][ct][cg], 287 vp6_huff_coeff_map, 12, 288 &s->ract_vlc[pt][ct][cg]); 289 } 290 memset(s->nb_null, 0, sizeof(s->nb_null)); 291 } else { 292 /* coeff_dcct is a linear combination of coeff_dccv */ 293 for (pt=0; pt<2; pt++) 294 for (ctx=0; ctx<3; ctx++) 295 for (node=0; node<5; node++) 296 model->coeff_dcct[pt][ctx][node] = av_clip(((model->coeff_dccv[pt][node] * vp6_dccv_lc[ctx][node][0] + 128) >> 8) + vp6_dccv_lc[ctx][node][1], 1, 255); 297 } 298} 299 300static void vp6_parse_vector_adjustment(VP56Context *s, VP56mv *vect) 301{ 302 VP56RangeCoder *c = &s->c; 303 VP56Model *model = s->modelp; 304 int comp; 305 306 *vect = (VP56mv) {0,0}; 307 if (s->vector_candidate_pos < 2) 308 *vect = s->vector_candidate[0]; 309 310 for (comp=0; comp<2; comp++) { 311 int i, delta = 0; 312 313 if (vp56_rac_get_prob(c, model->vector_dct[comp])) { 314 static const uint8_t prob_order[] = {0, 1, 2, 7, 6, 5, 4}; 315 for (i=0; i<sizeof(prob_order); i++) { 316 int j = prob_order[i]; 317 delta |= vp56_rac_get_prob(c, model->vector_fdv[comp][j])<<j; 318 } 319 if (delta & 0xF0) 320 delta |= vp56_rac_get_prob(c, model->vector_fdv[comp][3])<<3; 321 else 322 delta |= 8; 323 } else { 324 delta = vp56_rac_get_tree(c, vp56_pva_tree, 325 model->vector_pdv[comp]); 326 } 327 328 if (delta && vp56_rac_get_prob(c, model->vector_sig[comp])) 329 delta = -delta; 330 331 if (!comp) 332 vect->x += delta; 333 else 334 vect->y += delta; 335 } 336} 337 338/** 339 * Read number of consecutive blocks with null DC or AC. 340 * This value is < 74. 341 */ 342static unsigned vp6_get_nb_null(VP56Context *s) 343{ 344 unsigned val = get_bits(&s->gb, 2); 345 if (val == 2) 346 val += get_bits(&s->gb, 2); 347 else if (val == 3) { 348 val = get_bits1(&s->gb) << 2; 349 val = 6+val + get_bits(&s->gb, 2+val); 350 } 351 return val; 352} 353 354static void vp6_parse_coeff_huffman(VP56Context *s) 355{ 356 VP56Model *model = s->modelp; 357 uint8_t *permute = s->scantable.permutated; 358 VLC *vlc_coeff; 359 int coeff, sign, coeff_idx; 360 int b, cg, idx; 361 int pt = 0; /* plane type (0 for Y, 1 for U or V) */ 362 363 for (b=0; b<6; b++) { 364 int ct = 0; /* code type */ 365 if (b > 3) pt = 1; 366 vlc_coeff = &s->dccv_vlc[pt]; 367 368 for (coeff_idx=0; coeff_idx<64; ) { 369 int run = 1; 370 if (coeff_idx<2 && s->nb_null[coeff_idx][pt]) { 371 s->nb_null[coeff_idx][pt]--; 372 if (coeff_idx) 373 break; 374 } else { 375 coeff = get_vlc2(&s->gb, vlc_coeff->table, 9, 3); 376 if (coeff == 0) { 377 if (coeff_idx) { 378 int pt = (coeff_idx >= 6); 379 run += get_vlc2(&s->gb, s->runv_vlc[pt].table, 9, 3); 380 if (run >= 9) 381 run += get_bits(&s->gb, 6); 382 } else 383 s->nb_null[0][pt] = vp6_get_nb_null(s); 384 ct = 0; 385 } else if (coeff == 11) { /* end of block */ 386 if (coeff_idx == 1) /* first AC coeff ? */ 387 s->nb_null[1][pt] = vp6_get_nb_null(s); 388 break; 389 } else { 390 int coeff2 = vp56_coeff_bias[coeff]; 391 if (coeff > 4) 392 coeff2 += get_bits(&s->gb, coeff <= 9 ? coeff - 4 : 11); 393 ct = 1 + (coeff2 > 1); 394 sign = get_bits1(&s->gb); 395 coeff2 = (coeff2 ^ -sign) + sign; 396 if (coeff_idx) 397 coeff2 *= s->dequant_ac; 398 idx = model->coeff_index_to_pos[coeff_idx]; 399 s->block_coeff[b][permute[idx]] = coeff2; 400 } 401 } 402 coeff_idx+=run; 403 cg = FFMIN(vp6_coeff_groups[coeff_idx], 3); 404 vlc_coeff = &s->ract_vlc[pt][ct][cg]; 405 } 406 } 407} 408 409static void vp6_parse_coeff(VP56Context *s) 410{ 411 VP56RangeCoder *c = s->ccp; 412 VP56Model *model = s->modelp; 413 uint8_t *permute = s->scantable.permutated; 414 uint8_t *model1, *model2, *model3; 415 int coeff, sign, coeff_idx; 416 int b, i, cg, idx, ctx; 417 int pt = 0; /* plane type (0 for Y, 1 for U or V) */ 418 419 for (b=0; b<6; b++) { 420 int ct = 1; /* code type */ 421 int run = 1; 422 423 if (b > 3) pt = 1; 424 425 ctx = s->left_block[vp56_b6to4[b]].not_null_dc 426 + s->above_blocks[s->above_block_idx[b]].not_null_dc; 427 model1 = model->coeff_dccv[pt]; 428 model2 = model->coeff_dcct[pt][ctx]; 429 430 for (coeff_idx=0; coeff_idx<64; ) { 431 if ((coeff_idx>1 && ct==0) || vp56_rac_get_prob(c, model2[0])) { 432 /* parse a coeff */ 433 if (vp56_rac_get_prob(c, model2[2])) { 434 if (vp56_rac_get_prob(c, model2[3])) { 435 idx = vp56_rac_get_tree(c, vp56_pc_tree, model1); 436 coeff = vp56_coeff_bias[idx+5]; 437 for (i=vp56_coeff_bit_length[idx]; i>=0; i--) 438 coeff += vp56_rac_get_prob(c, vp56_coeff_parse_table[idx][i]) << i; 439 } else { 440 if (vp56_rac_get_prob(c, model2[4])) 441 coeff = 3 + vp56_rac_get_prob(c, model1[5]); 442 else 443 coeff = 2; 444 } 445 ct = 2; 446 } else { 447 ct = 1; 448 coeff = 1; 449 } 450 sign = vp56_rac_get(c); 451 coeff = (coeff ^ -sign) + sign; 452 if (coeff_idx) 453 coeff *= s->dequant_ac; 454 idx = model->coeff_index_to_pos[coeff_idx]; 455 s->block_coeff[b][permute[idx]] = coeff; 456 run = 1; 457 } else { 458 /* parse a run */ 459 ct = 0; 460 if (coeff_idx > 0) { 461 if (!vp56_rac_get_prob(c, model2[1])) 462 break; 463 464 model3 = model->coeff_runv[coeff_idx >= 6]; 465 run = vp56_rac_get_tree(c, vp6_pcr_tree, model3); 466 if (!run) 467 for (run=9, i=0; i<6; i++) 468 run += vp56_rac_get_prob(c, model3[i+8]) << i; 469 } 470 } 471 472 cg = vp6_coeff_groups[coeff_idx+=run]; 473 model1 = model2 = model->coeff_ract[pt][ct][cg]; 474 } 475 476 s->left_block[vp56_b6to4[b]].not_null_dc = 477 s->above_blocks[s->above_block_idx[b]].not_null_dc = !!s->block_coeff[b][0]; 478 } 479} 480 481static int vp6_adjust(int v, int t) 482{ 483 int V = v, s = v >> 31; 484 V ^= s; 485 V -= s; 486 if (V-t-1 >= (unsigned)(t-1)) 487 return v; 488 V = 2*t - V; 489 V += s; 490 V ^= s; 491 return V; 492} 493 494static int vp6_block_variance(uint8_t *src, int stride) 495{ 496 int sum = 0, square_sum = 0; 497 int y, x; 498 499 for (y=0; y<8; y+=2) { 500 for (x=0; x<8; x+=2) { 501 sum += src[x]; 502 square_sum += src[x]*src[x]; 503 } 504 src += 2*stride; 505 } 506 return (16*square_sum - sum*sum) >> 8; 507} 508 509static void vp6_filter_hv4(uint8_t *dst, uint8_t *src, int stride, 510 int delta, const int16_t *weights) 511{ 512 int x, y; 513 514 for (y=0; y<8; y++) { 515 for (x=0; x<8; x++) { 516 dst[x] = av_clip_uint8(( src[x-delta ] * weights[0] 517 + src[x ] * weights[1] 518 + src[x+delta ] * weights[2] 519 + src[x+2*delta] * weights[3] + 64) >> 7); 520 } 521 src += stride; 522 dst += stride; 523 } 524} 525 526static void vp6_filter_diag2(VP56Context *s, uint8_t *dst, uint8_t *src, 527 int stride, int h_weight, int v_weight) 528{ 529 uint8_t *tmp = s->edge_emu_buffer+16; 530 s->dsp.put_h264_chroma_pixels_tab[0](tmp, src, stride, 9, h_weight, 0); 531 s->dsp.put_h264_chroma_pixels_tab[0](dst, tmp, stride, 8, 0, v_weight); 532} 533 534static void vp6_filter(VP56Context *s, uint8_t *dst, uint8_t *src, 535 int offset1, int offset2, int stride, 536 VP56mv mv, int mask, int select, int luma) 537{ 538 int filter4 = 0; 539 int x8 = mv.x & mask; 540 int y8 = mv.y & mask; 541 542 if (luma) { 543 x8 *= 2; 544 y8 *= 2; 545 filter4 = s->filter_mode; 546 if (filter4 == 2) { 547 if (s->max_vector_length && 548 (FFABS(mv.x) > s->max_vector_length || 549 FFABS(mv.y) > s->max_vector_length)) { 550 filter4 = 0; 551 } else if (s->sample_variance_threshold 552 && (vp6_block_variance(src+offset1, stride) 553 < s->sample_variance_threshold)) { 554 filter4 = 0; 555 } 556 } 557 } 558 559 if ((y8 && (offset2-offset1)*s->flip<0) || (!y8 && offset1 > offset2)) { 560 offset1 = offset2; 561 } 562 563 if (filter4) { 564 if (!y8) { /* left or right combine */ 565 vp6_filter_hv4(dst, src+offset1, stride, 1, 566 vp6_block_copy_filter[select][x8]); 567 } else if (!x8) { /* above or below combine */ 568 vp6_filter_hv4(dst, src+offset1, stride, stride, 569 vp6_block_copy_filter[select][y8]); 570 } else { 571 s->dsp.vp6_filter_diag4(dst, src+offset1+((mv.x^mv.y)>>31), stride, 572 vp6_block_copy_filter[select][x8], 573 vp6_block_copy_filter[select][y8]); 574 } 575 } else { 576 if (!x8 || !y8) { 577 s->dsp.put_h264_chroma_pixels_tab[0](dst, src+offset1, stride, 8, x8, y8); 578 } else { 579 vp6_filter_diag2(s, dst, src+offset1 + ((mv.x^mv.y)>>31), stride, x8, y8); 580 } 581 } 582} 583 584static av_cold int vp6_decode_init(AVCodecContext *avctx) 585{ 586 VP56Context *s = avctx->priv_data; 587 588 vp56_init(avctx, avctx->codec->id == CODEC_ID_VP6, 589 avctx->codec->id == CODEC_ID_VP6A); 590 s->vp56_coord_div = vp6_coord_div; 591 s->parse_vector_adjustment = vp6_parse_vector_adjustment; 592 s->adjust = vp6_adjust; 593 s->filter = vp6_filter; 594 s->default_models_init = vp6_default_models_init; 595 s->parse_vector_models = vp6_parse_vector_models; 596 s->parse_coeff_models = vp6_parse_coeff_models; 597 s->parse_header = vp6_parse_header; 598 599 return 0; 600} 601 602AVCodec vp6_decoder = { 603 "vp6", 604 CODEC_TYPE_VIDEO, 605 CODEC_ID_VP6, 606 sizeof(VP56Context), 607 vp6_decode_init, 608 NULL, 609 vp56_free, 610 vp56_decode_frame, 611 CODEC_CAP_DR1, 612 .long_name = NULL_IF_CONFIG_SMALL("On2 VP6"), 613}; 614 615/* flash version, not flipped upside-down */ 616AVCodec vp6f_decoder = { 617 "vp6f", 618 CODEC_TYPE_VIDEO, 619 CODEC_ID_VP6F, 620 sizeof(VP56Context), 621 vp6_decode_init, 622 NULL, 623 vp56_free, 624 vp56_decode_frame, 625 CODEC_CAP_DR1, 626 .long_name = NULL_IF_CONFIG_SMALL("On2 VP6 (Flash version)"), 627}; 628 629/* flash version, not flipped upside-down, with alpha channel */ 630AVCodec vp6a_decoder = { 631 "vp6a", 632 CODEC_TYPE_VIDEO, 633 CODEC_ID_VP6A, 634 sizeof(VP56Context), 635 vp6_decode_init, 636 NULL, 637 vp56_free, 638 vp56_decode_frame, 639 CODEC_CAP_DR1, 640 .long_name = NULL_IF_CONFIG_SMALL("On2 VP6 (Flash version, with alpha channel)"), 641}; 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