FFmpeg: libavcodec/h263dec.c Source File

FFmpeg

[フレーム]

libavcodec

h263dec.c

Go to the documentation of this file.

1 /*

2 * H.263 decoder

5 *

6 * This file is part of FFmpeg.

7 *

8 * FFmpeg is free software; you can redistribute it and/or

9 * modify it under the terms of the GNU Lesser General Public

10 * License as published by the Free Software Foundation; either

11 * version 2.1 of the License, or (at your option) any later version.

12 *

13 * FFmpeg is distributed in the hope that it will be useful,

14 * but WITHOUT ANY WARRANTY; without even the implied warranty of

15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

16 * Lesser General Public License for more details.

17 *

18 * You should have received a copy of the GNU Lesser General Public

19 * License along with FFmpeg; if not, write to the Free Software

20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

21 */

23 /**

24 * @file

25 * H.263 decoder.

26 */

28 #define UNCHECKED_BITSTREAM_READER 1

30 #include "libavutil/cpu.h"

31 #include "avcodec.h"

32 #include "error_resilience.h"

33 #include "flv.h"

34 #include "h263.h"

35 #include "h263_parser.h"

36 #include "internal.h"

37 #include "mpeg_er.h"

38 #include "mpeg4video.h"

39 #include "mpeg4video_parser.h"

40 #include "mpegvideo.h"

41 #include "msmpeg4.h"

42 #include "qpeldsp.h"

43 #include "vdpau_internal.h"

44 #include "thread.h"

46 static enum AVPixelFormat h263_get_format(AVCodecContext *avctx)

47 {

48 if (avctx->codec->id == AV_CODEC_ID_MSS2)

49 return AV_PIX_FMT_YUV420P;

51 return avctx->pix_fmt = ff_get_format(avctx, avctx->codec->pix_fmts);

52 }

54 av_cold int ff_h263_decode_init(AVCodecContext *avctx)

55 {

56 MpegEncContext *s = avctx->priv_data;

57 int ret;

59 s->out_format = FMT_H263;

61 // set defaults

62 ff_mpv_decode_defaults(s);

63 ff_mpv_decode_init(s, avctx);

65 s->quant_precision = 5;

66 s->decode_mb = ff_h263_decode_mb;

67 s->low_delay = 1;

68 s->unrestricted_mv = 1;

70 /* select sub codec */

71 switch (avctx->codec->id) {

72 case AV_CODEC_ID_H263:

73 case AV_CODEC_ID_H263P:

74 s->unrestricted_mv = 0;

75 avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;

76 break;

77 case AV_CODEC_ID_MPEG4:

78 break;

79 case AV_CODEC_ID_MSMPEG4V1:

80 s->h263_pred = 1;

81 s->msmpeg4_version = 1;

82 break;

83 case AV_CODEC_ID_MSMPEG4V2:

84 s->h263_pred = 1;

85 s->msmpeg4_version = 2;

86 break;

87 case AV_CODEC_ID_MSMPEG4V3:

88 s->h263_pred = 1;

89 s->msmpeg4_version = 3;

90 break;

91 case AV_CODEC_ID_WMV1:

92 s->h263_pred = 1;

93 s->msmpeg4_version = 4;

94 break;

95 case AV_CODEC_ID_WMV2:

96 s->h263_pred = 1;

97 s->msmpeg4_version = 5;

98 break;

99 case AV_CODEC_ID_VC1:

100 case AV_CODEC_ID_WMV3:

101 case AV_CODEC_ID_VC1IMAGE:

102 case AV_CODEC_ID_WMV3IMAGE:

103 case AV_CODEC_ID_MSS2:

104 s->h263_pred = 1;

105 s->msmpeg4_version = 6;

106 avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;

107 break;

108 case AV_CODEC_ID_H263I:

109 break;

110 case AV_CODEC_ID_FLV1:

111 s->h263_flv = 1;

112 break;

113 default:

114 av_log(avctx, AV_LOG_ERROR, "Unsupported codec %d\n",

115 avctx->codec->id);

116 return AVERROR(ENOSYS);

117 }

118 s->codec_id = avctx->codec->id;

119

120 if (avctx->codec_tag == AV_RL32("L263") || avctx->codec_tag == AV_RL32("S263"))

121 if (avctx->extradata_size == 56 && avctx->extradata[0] == 1)

122 s->ehc_mode = 1;

123

124 /* for h263, we allocate the images after having read the header */

125 if (avctx->codec->id != AV_CODEC_ID_H263 &&

126 avctx->codec->id != AV_CODEC_ID_H263P &&

127 avctx->codec->id != AV_CODEC_ID_MPEG4) {

128 avctx->pix_fmt = h263_get_format(avctx);

129 ff_mpv_idct_init(s);

130 if ((ret = ff_mpv_common_init(s)) < 0)

131 return ret;

132 }

133

134 ff_h263dsp_init(&s->h263dsp);

135 ff_qpeldsp_init(&s->qdsp);

136 ff_h263_decode_init_vlc();

137

138 return 0;

139 }

140

141 av_cold int ff_h263_decode_end(AVCodecContext *avctx)

142 {

143 MpegEncContext *s = avctx->priv_data;

144

145 ff_mpv_common_end(s);

146 return 0;

147 }

148

149 /**

150 * Return the number of bytes consumed for building the current frame.

151 */

152 static int get_consumed_bytes(MpegEncContext *s, int buf_size)

153 {

154 int pos = (get_bits_count(&s->gb) + 7) >> 3;

155

156 if (s->divx_packed || s->avctx->hwaccel) {

157 /* We would have to scan through the whole buf to handle the weird

158 * reordering ... */

159 return buf_size;

160 } else if (s->flags & CODEC_FLAG_TRUNCATED) {

161 pos -= s->parse_context.last_index;

162 // padding is not really read so this might be -1

163 if (pos < 0)

164 pos = 0;

165 return pos;

166 } else {

167 // avoid infinite loops (maybe not needed...)

168 if (pos == 0)

169 pos = 1;

170 // oops ;)

171 if (pos + 10 > buf_size)

172 pos = buf_size;

173

174 return pos;

175 }

176 }

177

178 static int decode_slice(MpegEncContext *s)

179 {

180 const int part_mask = s->partitioned_frame

181 ? (ER_AC_END | ER_AC_ERROR) : 0x7F;

182 const int mb_size = 16 >> s->avctx->lowres;

183 int ret;

184

185 s->last_resync_gb = s->gb;

186 s->first_slice_line = 1;

187 s->resync_mb_x = s->mb_x;

188 s->resync_mb_y = s->mb_y;

189

190 ff_set_qscale(s, s->qscale);

191

192 if (s->avctx->hwaccel) {

193 const uint8_t *start = s->gb.buffer + get_bits_count(&s->gb) / 8;

194 ret = s->avctx->hwaccel->decode_slice(s->avctx, start, s->gb.buffer_end - start);

195 // ensure we exit decode loop

196 s->mb_y = s->mb_height;

197 return ret;

198 }

199

200 if (s->partitioned_frame) {

201 const int qscale = s->qscale;

202

203 if (CONFIG_MPEG4_DECODER && s->codec_id == AV_CODEC_ID_MPEG4)

204 if ((ret = ff_mpeg4_decode_partitions(s->avctx->priv_data)) < 0)

205 return ret;

206

207 /* restore variables which were modified */

208 s->first_slice_line = 1;

209 s->mb_x = s->resync_mb_x;

210 s->mb_y = s->resync_mb_y;

211 ff_set_qscale(s, qscale);

212 }

213

214 for (; s->mb_y < s->mb_height; s->mb_y++) {

215 /* per-row end of slice checks */

216 if (s->msmpeg4_version) {

217 if (s->resync_mb_y + s->slice_height == s->mb_y) {

218 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,

219 s->mb_x - 1, s->mb_y, ER_MB_END);

220

221 return 0;

222 }

223 }

224

225 if (s->msmpeg4_version == 1) {

226 s->last_dc[0] =

227 s->last_dc[1] =

228 s->last_dc[2] = 128;

229 }

230

231 ff_init_block_index(s);

232 for (; s->mb_x < s->mb_width; s->mb_x++) {

233 int ret;

234

235 ff_update_block_index(s);

236

237 if (s->resync_mb_x == s->mb_x && s->resync_mb_y + 1 == s->mb_y)

238 s->first_slice_line = 0;

239

240 /* DCT & quantize */

241

242 s->mv_dir = MV_DIR_FORWARD;

243 s->mv_type = MV_TYPE_16X16;

244 av_dlog(s, "%d %d %06X\n",

245 ret, get_bits_count(&s->gb), show_bits(&s->gb, 24));

246

247 tprintf(NULL, "Decoding MB at %dx%d\n", s->mb_x, s->mb_y);

248 ret = s->decode_mb(s, s->block);

249

250 if (s->pict_type != AV_PICTURE_TYPE_B)

251 ff_h263_update_motion_val(s);

252

253 if (ret < 0) {

254 const int xy = s->mb_x + s->mb_y * s->mb_stride;

255 if (ret == SLICE_END) {

256 ff_mpv_decode_mb(s, s->block);

257 if (s->loop_filter)

258 ff_h263_loop_filter(s);

259

260 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,

261 s->mb_x, s->mb_y, ER_MB_END & part_mask);

262

263 s->padding_bug_score--;

264

265 if (++s->mb_x >= s->mb_width) {

266 s->mb_x = 0;

267 ff_mpeg_draw_horiz_band(s, s->mb_y * mb_size, mb_size);

268 ff_mpv_report_decode_progress(s);

269 s->mb_y++;

270 }

271 return 0;

272 } else if (ret == SLICE_NOEND) {

273 av_log(s->avctx, AV_LOG_ERROR,

274 "Slice mismatch at MB: %d\n", xy);

275 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,

276 s->mb_x + 1, s->mb_y,

277 ER_MB_END & part_mask);

278 return AVERROR_INVALIDDATA;

279 }

280 av_log(s->avctx, AV_LOG_ERROR, "Error at MB: %d\n", xy);

281 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,

282 s->mb_x, s->mb_y, ER_MB_ERROR & part_mask);

283

284 if (s->err_recognition & AV_EF_IGNORE_ERR)

285 continue;

286 return AVERROR_INVALIDDATA;

287 }

288

289 ff_mpv_decode_mb(s, s->block);

290 if (s->loop_filter)

291 ff_h263_loop_filter(s);

292 }

293

294 ff_mpeg_draw_horiz_band(s, s->mb_y * mb_size, mb_size);

295 ff_mpv_report_decode_progress(s);

296

297 s->mb_x = 0;

298 }

299

300 av_assert1(s->mb_x == 0 && s->mb_y == s->mb_height);

301

302 if (s->codec_id == AV_CODEC_ID_MPEG4 &&

303 (s->workaround_bugs & FF_BUG_AUTODETECT) &&

304 get_bits_left(&s->gb) >= 48 &&

305 show_bits(&s->gb, 24) == 0x4010 &&

306 !s->data_partitioning)

307 s->padding_bug_score += 32;

308

309 /* try to detect the padding bug */

310 if (s->codec_id == AV_CODEC_ID_MPEG4 &&

311 (s->workaround_bugs & FF_BUG_AUTODETECT) &&

312 get_bits_left(&s->gb) >= 0 &&

313 get_bits_left(&s->gb) < 137 &&

314 !s->data_partitioning) {

315 const int bits_count = get_bits_count(&s->gb);

316 const int bits_left = s->gb.size_in_bits - bits_count;

317

318 if (bits_left == 0) {

319 s->padding_bug_score += 16;

320 } else if (bits_left != 1) {

321 int v = show_bits(&s->gb, 8);

322 v |= 0x7F >> (7 - (bits_count & 7));

323

324 if (v == 0x7F && bits_left <= 8)

325 s->padding_bug_score--;

326 else if (v == 0x7F && ((get_bits_count(&s->gb) + 8) & 8) &&

327 bits_left <= 16)

328 s->padding_bug_score += 4;

329 else

330 s->padding_bug_score++;

331 }

332 }

333

334 if (s->codec_id == AV_CODEC_ID_H263 &&

335 (s->workaround_bugs & FF_BUG_AUTODETECT) &&

336 get_bits_left(&s->gb) >= 8 &&

337 get_bits_left(&s->gb) < 300 &&

338 s->pict_type == AV_PICTURE_TYPE_I &&

339 show_bits(&s->gb, 8) == 0 &&

340 !s->data_partitioning) {

341

342 s->padding_bug_score += 32;

343 }

344

345 if (s->codec_id == AV_CODEC_ID_H263 &&

346 (s->workaround_bugs & FF_BUG_AUTODETECT) &&

347 get_bits_left(&s->gb) >= 64 &&

348 AV_RB64(s->gb.buffer_end - 8) == 0xCDCDCDCDFC7F0000) {

349

350 s->padding_bug_score += 32;

351 }

352

353 if (s->workaround_bugs & FF_BUG_AUTODETECT) {

354 if (

355 (s->padding_bug_score > -2 && !s->data_partitioning))

356 s->workaround_bugs |= FF_BUG_NO_PADDING;

357 else

358 s->workaround_bugs &= ~FF_BUG_NO_PADDING;

359 }

360

361 // handle formats which don't have unique end markers

362 if (s->msmpeg4_version || (s->workaround_bugs & FF_BUG_NO_PADDING)) { // FIXME perhaps solve this more cleanly

363 int left = get_bits_left(&s->gb);

364 int max_extra = 7;

365

366 /* no markers in M$ crap */

367 if (s->msmpeg4_version && s->pict_type == AV_PICTURE_TYPE_I)

368 max_extra += 17;

369

370 /* buggy padding but the frame should still end approximately at

371 * the bitstream end */

372 if ((s->workaround_bugs & FF_BUG_NO_PADDING) &&

373 (s->err_recognition & (AV_EF_BUFFER|AV_EF_AGGRESSIVE)))

374 max_extra += 48;

375 else if ((s->workaround_bugs & FF_BUG_NO_PADDING))

376 max_extra += 256 * 256 * 256 * 64;

377

378 if (left > max_extra)

379 av_log(s->avctx, AV_LOG_ERROR,

380 "discarding %d junk bits at end, next would be %X\n",

381 left, show_bits(&s->gb, 24));

382 else if (left < 0)

383 av_log(s->avctx, AV_LOG_ERROR, "overreading %d bits\n", -left);

384 else

385 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,

386 s->mb_x - 1, s->mb_y, ER_MB_END);

387

388 return 0;

389 }

390

391 av_log(s->avctx, AV_LOG_ERROR,

392 "slice end not reached but screenspace end (%d left %06X, score= %d)\n",

393 get_bits_left(&s->gb), show_bits(&s->gb, 24), s->padding_bug_score);

394

395 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y,

396 ER_MB_END & part_mask);

397

398 return AVERROR_INVALIDDATA;

399 }

400

401 int ff_h263_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,

402 AVPacket *avpkt)

403 {

404 const uint8_t *buf = avpkt->data;

405 int buf_size = avpkt->size;

406 MpegEncContext *s = avctx->priv_data;

407 int ret;

408 int slice_ret = 0;

409 AVFrame *pict = data;

410

411 s->flags = avctx->flags;

412 s->flags2 = avctx->flags2;

413

414 /* no supplementary picture */

415 if (buf_size == 0) {

416 /* special case for last picture */

417 if (s->low_delay == 0 && s->next_picture_ptr) {

418 if ((ret = av_frame_ref(pict, s->next_picture_ptr->f)) < 0)

419 return ret;

420 s->next_picture_ptr = NULL;

421

422 *got_frame = 1;

423 }

424

425 return 0;

426 }

427

428 if (s->flags & CODEC_FLAG_TRUNCATED) {

429 int next;

430

431 if (CONFIG_MPEG4_DECODER && s->codec_id == AV_CODEC_ID_MPEG4) {

432 next = ff_mpeg4_find_frame_end(&s->parse_context, buf, buf_size);

433 } else if (CONFIG_H263_DECODER && s->codec_id == AV_CODEC_ID_H263) {

434 next = ff_h263_find_frame_end(&s->parse_context, buf, buf_size);

435 } else if (CONFIG_H263P_DECODER && s->codec_id == AV_CODEC_ID_H263P) {

436 next = ff_h263_find_frame_end(&s->parse_context, buf, buf_size);

437 } else {

438 av_log(s->avctx, AV_LOG_ERROR,

439 "this codec does not support truncated bitstreams\n");

440 return AVERROR(ENOSYS);

441 }

442

443 if (ff_combine_frame(&s->parse_context, next, (const uint8_t **)&buf,

444 &buf_size) < 0)

445 return buf_size;

446 }

447

448 retry:

449 if (s->divx_packed && s->bitstream_buffer_size) {

450 int i;

451 for(i=0; i < buf_size-3; i++) {

452 if (buf[i]==0 && buf[i+1]==0 && buf[i+2]==1) {

453 if (buf[i+3]==0xB0) {

454 av_log(s->avctx, AV_LOG_WARNING, "Discarding excessive bitstream in packed xvid\n");

455 s->bitstream_buffer_size = 0;

456 }

457 break;

458 }

459 }

460 }

461

462 if (s->bitstream_buffer_size && (s->divx_packed || buf_size < 20)) // divx 5.01+/xvid frame reorder

463 ret = init_get_bits8(&s->gb, s->bitstream_buffer,

464 s->bitstream_buffer_size);

465 else

466 ret = init_get_bits8(&s->gb, buf, buf_size);

467

468 s->bitstream_buffer_size = 0;

469 if (ret < 0)

470 return ret;

471

472 if (!s->context_initialized)

473 // we need the idct permutaton for reading a custom matrix

474 ff_mpv_idct_init(s);

475

476 /* let's go :-) */

477 if (CONFIG_WMV2_DECODER && s->msmpeg4_version == 5) {

478 ret = ff_wmv2_decode_picture_header(s);

479 } else if (CONFIG_MSMPEG4_DECODER && s->msmpeg4_version) {

480 ret = ff_msmpeg4_decode_picture_header(s);

481 } else if (CONFIG_MPEG4_DECODER && avctx->codec_id == AV_CODEC_ID_MPEG4) {

482 if (s->avctx->extradata_size && s->picture_number == 0) {

483 GetBitContext gb;

484

485 if (init_get_bits8(&gb, s->avctx->extradata, s->avctx->extradata_size) >= 0 )

486 ff_mpeg4_decode_picture_header(avctx->priv_data, &gb);

487 }

488 ret = ff_mpeg4_decode_picture_header(avctx->priv_data, &s->gb);

489 } else if (CONFIG_H263I_DECODER && s->codec_id == AV_CODEC_ID_H263I) {

490 ret = ff_intel_h263_decode_picture_header(s);

491 } else if (CONFIG_FLV_DECODER && s->h263_flv) {

492 ret = ff_flv_decode_picture_header(s);

493 } else {

494 ret = ff_h263_decode_picture_header(s);

495 }

496

497 if (ret < 0 || ret == FRAME_SKIPPED) {

498 if ( s->width != avctx->coded_width

499 || s->height != avctx->coded_height) {

500 av_log(s->avctx, AV_LOG_WARNING, "Reverting picture dimensions change due to header decoding failure\n");

501 s->width = avctx->coded_width;

502 s->height= avctx->coded_height;

503 }

504 }

505 if (ret == FRAME_SKIPPED)

506 return get_consumed_bytes(s, buf_size);

507

508 /* skip if the header was thrashed */

509 if (ret < 0) {

510 av_log(s->avctx, AV_LOG_ERROR, "header damaged\n");

511 return ret;

512 }

513

514 if (!s->context_initialized) {

515 avctx->pix_fmt = h263_get_format(avctx);

516 if ((ret = ff_mpv_common_init(s)) < 0)

517 return ret;

518 }

519

520 if (!s->current_picture_ptr || s->current_picture_ptr->f->data[0]) {

521 int i = ff_find_unused_picture(s, 0);

522 if (i < 0)

523 return i;

524 s->current_picture_ptr = &s->picture[i];

525 }

526

527 avctx->has_b_frames = !s->low_delay;

528

529 if (CONFIG_MPEG4_DECODER && avctx->codec_id == AV_CODEC_ID_MPEG4) {

530 if (ff_mpeg4_workaround_bugs(avctx) == 1)

531 goto retry;

532 }

533

534 /* After H263 & mpeg4 header decode we have the height, width,

535 * and other parameters. So then we could init the picture.

536 * FIXME: By the way H263 decoder is evolving it should have

537 * an H263EncContext */

538 if (s->width != avctx->coded_width ||

539 s->height != avctx->coded_height ||

540 s->context_reinit) {

541 /* H.263 could change picture size any time */

542 s->context_reinit = 0;

543

544 ret = ff_set_dimensions(avctx, s->width, s->height);

545 if (ret < 0)

546 return ret;

547

548 ff_set_sar(avctx, avctx->sample_aspect_ratio);

549

550 if ((ret = ff_mpv_common_frame_size_change(s)))

551 return ret;

552

553 if (avctx->pix_fmt != h263_get_format(avctx)) {

554 av_log(avctx, AV_LOG_ERROR, "format change not supported\n");

555 avctx->pix_fmt = AV_PIX_FMT_NONE;

556 return AVERROR_UNKNOWN;

557 }

558 }

559

560 if (s->codec_id == AV_CODEC_ID_H263 ||

561 s->codec_id == AV_CODEC_ID_H263P ||

562 s->codec_id == AV_CODEC_ID_H263I)

563 s->gob_index = ff_h263_get_gob_height(s);

564

565 // for skipping the frame

566 s->current_picture.f->pict_type = s->pict_type;

567 s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;

568

569 /* skip B-frames if we don't have reference frames */

570 if (!s->last_picture_ptr &&

571 (s->pict_type == AV_PICTURE_TYPE_B || s->droppable))

572 return get_consumed_bytes(s, buf_size);

573 if ((avctx->skip_frame >= AVDISCARD_NONREF &&

574 s->pict_type == AV_PICTURE_TYPE_B) ||

575 (avctx->skip_frame >= AVDISCARD_NONKEY &&

576 s->pict_type != AV_PICTURE_TYPE_I) ||

577 avctx->skip_frame >= AVDISCARD_ALL)

578 return get_consumed_bytes(s, buf_size);

579

580 if (s->next_p_frame_damaged) {

581 if (s->pict_type == AV_PICTURE_TYPE_B)

582 return get_consumed_bytes(s, buf_size);

583 else

584 s->next_p_frame_damaged = 0;

585 }

586

587 if ((!s->no_rounding) || s->pict_type == AV_PICTURE_TYPE_B) {

588 s->me.qpel_put = s->qdsp.put_qpel_pixels_tab;

589 s->me.qpel_avg = s->qdsp.avg_qpel_pixels_tab;

590 } else {

591 s->me.qpel_put = s->qdsp.put_no_rnd_qpel_pixels_tab;

592 s->me.qpel_avg = s->qdsp.avg_qpel_pixels_tab;

593 }

594

595 if ((ret = ff_mpv_frame_start(s, avctx)) < 0)

596 return ret;

597

598 if (!s->divx_packed && !avctx->hwaccel)

599 ff_thread_finish_setup(avctx);

600

601 if (CONFIG_MPEG4_VDPAU_DECODER && (s->avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)) {

602 ff_vdpau_mpeg4_decode_picture(avctx->priv_data, s->gb.buffer, s->gb.buffer_end - s->gb.buffer);

603 goto frame_end;

604 }

605

606 if (avctx->hwaccel) {

607 ret = avctx->hwaccel->start_frame(avctx, s->gb.buffer,

608 s->gb.buffer_end - s->gb.buffer);

609 if (ret < 0 )

610 return ret;

611 }

612

613 ff_mpeg_er_frame_start(s);

614

615 /* the second part of the wmv2 header contains the MB skip bits which

616 * are stored in current_picture->mb_type which is not available before

617 * ff_mpv_frame_start() */

618 if (CONFIG_WMV2_DECODER && s->msmpeg4_version == 5) {

619 ret = ff_wmv2_decode_secondary_picture_header(s);

620 if (ret < 0)

621 return ret;

622 if (ret == 1)

623 goto frame_end;

624 }

625

626 /* decode each macroblock */

627 s->mb_x = 0;

628 s->mb_y = 0;

629

630 slice_ret = decode_slice(s);

631 while (s->mb_y < s->mb_height) {

632 if (s->msmpeg4_version) {

633 if (s->slice_height == 0 || s->mb_x != 0 ||

634 (s->mb_y % s->slice_height) != 0 || get_bits_left(&s->gb) < 0)

635 break;

636 } else {

637 int prev_x = s->mb_x, prev_y = s->mb_y;

638 if (ff_h263_resync(s) < 0)

639 break;

640 if (prev_y * s->mb_width + prev_x < s->mb_y * s->mb_width + s->mb_x)

641 s->er.error_occurred = 1;

642 }

643

644 if (s->msmpeg4_version < 4 && s->h263_pred)

645 ff_mpeg4_clean_buffers(s);

646

647 if (decode_slice(s) < 0)

648 slice_ret = AVERROR_INVALIDDATA;

649 }

650

651 if (s->msmpeg4_version && s->msmpeg4_version < 4 &&

652 s->pict_type == AV_PICTURE_TYPE_I)

653 if (!CONFIG_MSMPEG4_DECODER ||

654 ff_msmpeg4_decode_ext_header(s, buf_size) < 0)

655 s->er.error_status_table[s->mb_num - 1] = ER_MB_ERROR;

656

657 av_assert1(s->bitstream_buffer_size == 0);

658 frame_end:

659 ff_er_frame_end(&s->er);

660

661 if (avctx->hwaccel) {

662 ret = avctx->hwaccel->end_frame(avctx);

663 if (ret < 0)

664 return ret;

665 }

666

667 ff_mpv_frame_end(s);

668

669 if (CONFIG_MPEG4_DECODER && avctx->codec_id == AV_CODEC_ID_MPEG4)

670 ff_mpeg4_frame_end(avctx, buf, buf_size);

671

672 if (!s->divx_packed && avctx->hwaccel)

673 ff_thread_finish_setup(avctx);

674

675 av_assert1(s->current_picture.f->pict_type == s->current_picture_ptr->f->pict_type);

676 av_assert1(s->current_picture.f->pict_type == s->pict_type);

677 if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {

678 if ((ret = av_frame_ref(pict, s->current_picture_ptr->f)) < 0)

679 return ret;

680 ff_print_debug_info(s, s->current_picture_ptr, pict);

681 ff_mpv_export_qp_table(s, pict, s->current_picture_ptr, FF_QSCALE_TYPE_MPEG1);

682 } else if (s->last_picture_ptr) {

683 if ((ret = av_frame_ref(pict, s->last_picture_ptr->f)) < 0)

684 return ret;

685 ff_print_debug_info(s, s->last_picture_ptr, pict);

686 ff_mpv_export_qp_table(s, pict, s->last_picture_ptr, FF_QSCALE_TYPE_MPEG1);

687 }

688

689 if (s->last_picture_ptr || s->low_delay) {

690 if ( pict->format == AV_PIX_FMT_YUV420P

691 && (s->codec_tag == AV_RL32("GEOV") || s->codec_tag == AV_RL32("GEOX"))) {

692 int x, y, p;

693 av_frame_make_writable(pict);

694 for (p=0; p<3; p++) {

695 int w = FF_CEIL_RSHIFT(pict-> width, !!p);

696 int h = FF_CEIL_RSHIFT(pict->height, !!p);

697 int linesize = pict->linesize[p];

698 for (y=0; y<(h>>1); y++)

699 for (x=0; x<w; x++)

700 FFSWAP(int,

701 pict->data[p][x + y*linesize],

702 pict->data[p][x + (h-1-y)*linesize]);

703 }

704 }

705 *got_frame = 1;

706 }

707

708 if (slice_ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))

709 return ret;

710 else

711 return get_consumed_bytes(s, buf_size);

712 }

713

714 const enum AVPixelFormat ff_h263_hwaccel_pixfmt_list_420[] = {

715 #if CONFIG_H263_VAAPI_HWACCEL || CONFIG_MPEG4_VAAPI_HWACCEL

716 AV_PIX_FMT_VAAPI_VLD,

717 #endif

718 #if CONFIG_H263_VDPAU_HWACCEL || CONFIG_MPEG4_VDPAU_HWACCEL

719 AV_PIX_FMT_VDPAU,

720 #endif

721 AV_PIX_FMT_YUV420P,

722 AV_PIX_FMT_NONE

723 };

724

725 AVCodec ff_h263_decoder = {

726 .name = "h263",

727 .long_name = NULL_IF_CONFIG_SMALL("H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2"),

728 .type = AVMEDIA_TYPE_VIDEO,

729 .id = AV_CODEC_ID_H263,

730 .priv_data_size = sizeof(MpegEncContext),

731 .init = ff_h263_decode_init,

732 .close = ff_h263_decode_end,

733 .decode = ff_h263_decode_frame,

734 .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |

735 CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,

736 .flush = ff_mpeg_flush,

737 .max_lowres = 3,

738 .pix_fmts = ff_h263_hwaccel_pixfmt_list_420,

739 };

740

741 AVCodec ff_h263p_decoder = {

742 .name = "h263p",

743 .long_name = NULL_IF_CONFIG_SMALL("H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2"),

744 .type = AVMEDIA_TYPE_VIDEO,

745 .id = AV_CODEC_ID_H263P,

746 .priv_data_size = sizeof(MpegEncContext),

747 .init = ff_h263_decode_init,

748 .close = ff_h263_decode_end,

749 .decode = ff_h263_decode_frame,

750 .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |

751 CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,

752 .flush = ff_mpeg_flush,

753 .max_lowres = 3,

754 .pix_fmts = ff_h263_hwaccel_pixfmt_list_420,

755 };

Generated on Sun Mar 8 2015 02:34:52 for FFmpeg by doxygen 1.8.2