FFmpeg: libavcodec/lagarith.c Source File

FFmpeg

[フレーム]

libavcodec

lagarith.c

Go to the documentation of this file.

1 /*

2 * Lagarith lossless decoder

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 */

22 /**

23 * @file

24 * Lagarith lossless decoder

25 * @author Nathan Caldwell

26 */

28 #include "avcodec.h"

29 #include "get_bits.h"

30 #include "mathops.h"

31 #include "dsputil.h"

32 #include "lagarithrac.h"

33 #include "thread.h"

35 enum LagarithFrameType {

36 FRAME_RAW = 1, /**< uncompressed */

37 FRAME_U_RGB24 = 2, /**< unaligned RGB24 */

38 FRAME_ARITH_YUY2 = 3, /**< arithmetic coded YUY2 */

39 FRAME_ARITH_RGB24 = 4, /**< arithmetic coded RGB24 */

40 FRAME_SOLID_GRAY = 5, /**< solid grayscale color frame */

41 FRAME_SOLID_COLOR = 6, /**< solid non-grayscale color frame */

42 FRAME_OLD_ARITH_RGB = 7, /**< obsolete arithmetic coded RGB (no longer encoded by upstream since version 1.1.0) */

43 FRAME_ARITH_RGBA = 8, /**< arithmetic coded RGBA */

44 FRAME_SOLID_RGBA = 9, /**< solid RGBA color frame */

45 FRAME_ARITH_YV12 = 10, /**< arithmetic coded YV12 */

46 FRAME_REDUCED_RES = 11, /**< reduced resolution YV12 frame */

47 };

49 typedef struct LagarithContext {

50 AVCodecContext *avctx;

51 DSPContext dsp;

52 int zeros; /**< number of consecutive zero bytes encountered */

53 int zeros_rem; /**< number of zero bytes remaining to output */

54 uint8_t *rgb_planes;

55 int rgb_stride;

56 } LagarithContext;

58 /**

59 * Compute the 52bit mantissa of 1/(double)denom.

60 * This crazy format uses floats in an entropy coder and we have to match x86

61 * rounding exactly, thus ordinary floats aren't portable enough.

62 * @param denom denominator

63 * @return 52bit mantissa

64 * @see softfloat_mul

65 */

66 static uint64_t softfloat_reciprocal(uint32_t denom)

67 {

68 int shift = av_log2(denom - 1) + 1;

69 uint64_t ret = (1ULL << 52) / denom;

70 uint64_t err = (1ULL << 52) - ret * denom;

71 ret <<= shift;

72 err <<= shift;

73 err += denom / 2;

74 return ret + err / denom;

75 }

77 /**

78 * (uint32_t)(x*f), where f has the given mantissa, and exponent 0

79 * Used in combination with softfloat_reciprocal computes x/(double)denom.

80 * @param x 32bit integer factor

81 * @param mantissa mantissa of f with exponent 0

82 * @return 32bit integer value (x*f)

83 * @see softfloat_reciprocal

84 */

85 static uint32_t softfloat_mul(uint32_t x, uint64_t mantissa)

86 {

87 uint64_t l = x * (mantissa & 0xffffffff);

88 uint64_t h = x * (mantissa >> 32);

89 h += l >> 32;

90 l &= 0xffffffff;

91 l += 1 << av_log2(h >> 21);

92 h += l >> 32;

93 return h >> 20;

94 }

96 static uint8_t lag_calc_zero_run(int8_t x)

97 {

98 return (x << 1) ^ (x >> 7);

99 }

100

101 static int lag_decode_prob(GetBitContext *gb, uint32_t *value)

102 {

103 static const uint8_t series[] = { 1, 2, 3, 5, 8, 13, 21 };

104 int i;

105 int bit = 0;

106 int bits = 0;

107 int prevbit = 0;

108 unsigned val;

109

110 for (i = 0; i < 7; i++) {

111 if (prevbit && bit)

112 break;

113 prevbit = bit;

114 bit = get_bits1(gb);

115 if (bit && !prevbit)

116 bits += series[i];

117 }

118 bits--;

119 if (bits < 0 || bits > 31) {

120 *value = 0;

121 return -1;

122 } else if (bits == 0) {

123 *value = 0;

124 return 0;

125 }

126

127 val = get_bits_long(gb, bits);

128 val |= 1 << bits;

129

130 *value = val - 1;

131

132 return 0;

133 }

134

135 static int lag_read_prob_header(lag_rac *rac, GetBitContext *gb)

136 {

137 int i, j, scale_factor;

138 unsigned prob, cumulative_target;

139 unsigned cumul_prob = 0;

140 unsigned scaled_cumul_prob = 0;

141

142 rac->prob[0] = 0;

143 rac->prob[257] = UINT_MAX;

144 /* Read probabilities from bitstream */

145 for (i = 1; i < 257; i++) {

146 if (lag_decode_prob(gb, &rac->prob[i]) < 0) {

147 av_log(rac->avctx, AV_LOG_ERROR, "Invalid probability encountered.\n");

148 return -1;

149 }

150 if ((uint64_t)cumul_prob + rac->prob[i] > UINT_MAX) {

151 av_log(rac->avctx, AV_LOG_ERROR, "Integer overflow encountered in cumulative probability calculation.\n");

152 return -1;

153 }

154 cumul_prob += rac->prob[i];

155 if (!rac->prob[i]) {

156 if (lag_decode_prob(gb, &prob)) {

157 av_log(rac->avctx, AV_LOG_ERROR, "Invalid probability run encountered.\n");

158 return -1;

159 }

160 if (prob > 256 - i)

161 prob = 256 - i;

162 for (j = 0; j < prob; j++)

163 rac->prob[++i] = 0;

164 }

165 }

166

167 if (!cumul_prob) {

168 av_log(rac->avctx, AV_LOG_ERROR, "All probabilities are 0!\n");

169 return -1;

170 }

171

172 /* Scale probabilities so cumulative probability is an even power of 2. */

173 scale_factor = av_log2(cumul_prob);

174

175 if (cumul_prob & (cumul_prob - 1)) {

176 uint64_t mul = softfloat_reciprocal(cumul_prob);

177 for (i = 1; i < 257; i++) {

178 rac->prob[i] = softfloat_mul(rac->prob[i], mul);

179 scaled_cumul_prob += rac->prob[i];

180 }

181

182 scale_factor++;

183 cumulative_target = 1 << scale_factor;

184

185 if (scaled_cumul_prob > cumulative_target) {

186 av_log(rac->avctx, AV_LOG_ERROR,

187 "Scaled probabilities are larger than target!\n");

188 return -1;

189 }

190

191 scaled_cumul_prob = cumulative_target - scaled_cumul_prob;

192

193 for (i = 1; scaled_cumul_prob; i = (i & 0x7f) + 1) {

194 if (rac->prob[i]) {

195 rac->prob[i]++;

196 scaled_cumul_prob--;

197 }

198 /* Comment from reference source:

199 * if (b & 0x80 == 0) { // order of operations is 'wrong'; it has been left this way

200 * // since the compression change is negligible and fixing it

201 * // breaks backwards compatibility

202 * b =- (signed int)b;

203 * b &= 0xFF;

204 * } else {

205 * b++;

206 * b &= 0x7f;

207 * }

208 */

209 }

210 }

211

212 rac->scale = scale_factor;

213

214 /* Fill probability array with cumulative probability for each symbol. */

215 for (i = 1; i < 257; i++)

216 rac->prob[i] += rac->prob[i - 1];

217

218 return 0;

219 }

220

221 static void add_lag_median_prediction(uint8_t *dst, uint8_t *src1,

222 uint8_t *diff, int w, int *left,

223 int *left_top)

224 {

225 /* This is almost identical to add_hfyu_median_prediction in dsputil.h.

226 * However the &0xFF on the gradient predictor yealds incorrect output

227 * for lagarith.

228 */

229 int i;

230 uint8_t l, lt;

231

232 l = *left;

233 lt = *left_top;

234

235 for (i = 0; i < w; i++) {

236 l = mid_pred(l, src1[i], l + src1[i] - lt) + diff[i];

237 lt = src1[i];

238 dst[i] = l;

239 }

240

241 *left = l;

242 *left_top = lt;

243 }

244

245 static void lag_pred_line(LagarithContext *l, uint8_t *buf,

246 int width, int stride, int line)

247 {

248 int L, TL;

249

250 if (!line) {

251 /* Left prediction only for first line */

252 L = l->dsp.add_hfyu_left_prediction(buf, buf,

253 width, 0);

254 } else {

255 /* Left pixel is actually prev_row[width] */

256 L = buf[width - stride - 1];

257

258 if (line == 1) {

259 /* Second line, left predict first pixel, the rest of the line is median predicted

260 * NOTE: In the case of RGB this pixel is top predicted */

261 TL = l->avctx->pix_fmt == AV_PIX_FMT_YUV420P ? buf[-stride] : L;

262 } else {

263 /* Top left is 2 rows back, last pixel */

264 TL = buf[width - (2 * stride) - 1];

265 }

266

267 add_lag_median_prediction(buf, buf - stride, buf,

268 width, &L, &TL);

269 }

270 }

271

272 static void lag_pred_line_yuy2(LagarithContext *l, uint8_t *buf,

273 int width, int stride, int line,

274 int is_luma)

275 {

276 int L, TL;

277

278 if (!line) {

279 L= buf[0];

280 if (is_luma)

281 buf[0] = 0;

282 l->dsp.add_hfyu_left_prediction(buf, buf, width, 0);

283 if (is_luma)

284 buf[0] = L;

285 return;

286 }

287 if (line == 1) {

288 const int HEAD = is_luma ? 4 : 2;

289 int i;

290

291 L = buf[width - stride - 1];

292 TL = buf[HEAD - stride - 1];

293 for (i = 0; i < HEAD; i++) {

294 L += buf[i];

295 buf[i] = L;

296 }

297 for (; i<width; i++) {

298 L = mid_pred(L&0xFF, buf[i-stride], (L + buf[i-stride] - TL)&0xFF) + buf[i];

299 TL = buf[i-stride];

300 buf[i]= L;

301 }

302 } else {

303 TL = buf[width - (2 * stride) - 1];

304 L = buf[width - stride - 1];

305 l->dsp.add_hfyu_median_prediction(buf, buf - stride, buf, width,

306 &L, &TL);

307 }

308 }

309

310 static int lag_decode_line(LagarithContext *l, lag_rac *rac,

311 uint8_t *dst, int width, int stride,

312 int esc_count)

313 {

314 int i = 0;

315 int ret = 0;

316

317 if (!esc_count)

318 esc_count = -1;

319

320 /* Output any zeros remaining from the previous run */

321 handle_zeros:

322 if (l->zeros_rem) {

323 int count = FFMIN(l->zeros_rem, width - i);

324 memset(dst + i, 0, count);

325 i += count;

326 l->zeros_rem -= count;

327 }

328

329 while (i < width) {

330 dst[i] = lag_get_rac(rac);

331 ret++;

332

333 if (dst[i])

334 l->zeros = 0;

335 else

336 l->zeros++;

337

338 i++;

339 if (l->zeros == esc_count) {

340 int index = lag_get_rac(rac);

341 ret++;

342

343 l->zeros = 0;

344

345 l->zeros_rem = lag_calc_zero_run(index);

346 goto handle_zeros;

347 }

348 }

349 return ret;

350 }

351

352 static int lag_decode_zero_run_line(LagarithContext *l, uint8_t *dst,

353 const uint8_t *src, const uint8_t *src_end,

354 int width, int esc_count)

355 {

356 int i = 0;

357 int count;

358 uint8_t zero_run = 0;

359 const uint8_t *src_start = src;

360 uint8_t mask1 = -(esc_count < 2);

361 uint8_t mask2 = -(esc_count < 3);

362 uint8_t *end = dst + (width - 2);

363

364 output_zeros:

365 if (l->zeros_rem) {

366 count = FFMIN(l->zeros_rem, width - i);

367 if (end - dst < count) {

368 av_log(l->avctx, AV_LOG_ERROR, "Too many zeros remaining.\n");

369 return AVERROR_INVALIDDATA;

370 }

371

372 memset(dst, 0, count);

373 l->zeros_rem -= count;

374 dst += count;

375 }

376

377 while (dst < end) {

378 i = 0;

379 while (!zero_run && dst + i < end) {

380 i++;

381 if (i+2 >= src_end - src)

382 return AVERROR_INVALIDDATA;

383 zero_run =

384 !(src[i] | (src[i + 1] & mask1) | (src[i + 2] & mask2));

385 }

386 if (zero_run) {

387 zero_run = 0;

388 i += esc_count;

389 memcpy(dst, src, i);

390 dst += i;

391 l->zeros_rem = lag_calc_zero_run(src[i]);

392

393 src += i + 1;

394 goto output_zeros;

395 } else {

396 memcpy(dst, src, i);

397 src += i;

398 dst += i;

399 }

400 }

401 return src - src_start;

402 }

403

404

405

406 static int lag_decode_arith_plane(LagarithContext *l, uint8_t *dst,

407 int width, int height, int stride,

408 const uint8_t *src, int src_size)

409 {

410 int i = 0;

411 int read = 0;

412 uint32_t length;

413 uint32_t offset = 1;

414 int esc_count;

415 GetBitContext gb;

416 lag_rac rac;

417 const uint8_t *src_end = src + src_size;

418

419 rac.avctx = l->avctx;

420 l->zeros = 0;

421

422 if(src_size < 2)

423 return AVERROR_INVALIDDATA;

424

425 esc_count = src[0];

426 if (esc_count < 4) {

427 length = width * height;

428 if(src_size < 5)

429 return AVERROR_INVALIDDATA;

430 if (esc_count && AV_RL32(src + 1) < length) {

431 length = AV_RL32(src + 1);

432 offset += 4;

433 }

434

435 init_get_bits(&gb, src + offset, src_size * 8);

436

437 if (lag_read_prob_header(&rac, &gb) < 0)

438 return -1;

439

440 ff_lag_rac_init(&rac, &gb, length - stride);

441

442 for (i = 0; i < height; i++)

443 read += lag_decode_line(l, &rac, dst + (i * stride), width,

444 stride, esc_count);

445

446 if (read > length)

447 av_log(l->avctx, AV_LOG_WARNING,

448 "Output more bytes than length (%d of %d)\n", read,

449 length);

450 } else if (esc_count < 8) {

451 esc_count -= 4;

452 if (esc_count > 0) {

453 /* Zero run coding only, no range coding. */

454 for (i = 0; i < height; i++) {

455 int res = lag_decode_zero_run_line(l, dst + (i * stride), src,

456 src_end, width, esc_count);

457 if (res < 0)

458 return res;

459 src += res;

460 }

461 } else {

462 if (src_size < width * height)

463 return AVERROR_INVALIDDATA; // buffer not big enough

464 /* Plane is stored uncompressed */

465 for (i = 0; i < height; i++) {

466 memcpy(dst + (i * stride), src, width);

467 src += width;

468 }

469 }

470 } else if (esc_count == 0xff) {

471 /* Plane is a solid run of given value */

472 for (i = 0; i < height; i++)

473 memset(dst + i * stride, src[1], width);

474 /* Do not apply prediction.

475 Note: memset to 0 above, setting first value to src[1]

476 and applying prediction gives the same result. */

477 return 0;

478 } else {

479 av_log(l->avctx, AV_LOG_ERROR,

480 "Invalid zero run escape code! (%#x)\n", esc_count);

481 return -1;

482 }

483

484 if (l->avctx->pix_fmt != AV_PIX_FMT_YUV422P) {

485 for (i = 0; i < height; i++) {

486 lag_pred_line(l, dst, width, stride, i);

487 dst += stride;

488 }

489 } else {

490 for (i = 0; i < height; i++) {

491 lag_pred_line_yuy2(l, dst, width, stride, i,

492 width == l->avctx->width);

493 dst += stride;

494 }

495 }

496

497 return 0;

498 }

499

500 /**

501 * Decode a frame.

502 * @param avctx codec context

503 * @param data output AVFrame

504 * @param data_size size of output data or 0 if no picture is returned

505 * @param avpkt input packet

506 * @return number of consumed bytes on success or negative if decode fails

507 */

508 static int lag_decode_frame(AVCodecContext *avctx,

509 void *data, int *got_frame, AVPacket *avpkt)

510 {

511 const uint8_t *buf = avpkt->data;

512 unsigned int buf_size = avpkt->size;

513 LagarithContext *l = avctx->priv_data;

514 ThreadFrame frame = { .f = data };

515 AVFrame *const p = data;

516 uint8_t frametype = 0;

517 uint32_t offset_gu = 0, offset_bv = 0, offset_ry = 9;

518 uint32_t offs[4];

519 uint8_t *srcs[4], *dst;

520 int i, j, planes = 3;

521 int ret;

522

523 p->key_frame = 1;

524

525 frametype = buf[0];

526

527 offset_gu = AV_RL32(buf + 1);

528 offset_bv = AV_RL32(buf + 5);

529

530 switch (frametype) {

531 case FRAME_SOLID_RGBA:

532 avctx->pix_fmt = AV_PIX_FMT_RGB32;

533 case FRAME_SOLID_GRAY:

534 if (frametype == FRAME_SOLID_GRAY)

535 if (avctx->bits_per_coded_sample == 24) {

536 avctx->pix_fmt = AV_PIX_FMT_RGB24;

537 } else {

538 avctx->pix_fmt = AV_PIX_FMT_0RGB32;

539 planes = 4;

540 }

541

542 if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)

543 return ret;

544

545 dst = p->data[0];

546 if (frametype == FRAME_SOLID_RGBA) {

547 for (j = 0; j < avctx->height; j++) {

548 for (i = 0; i < avctx->width; i++)

549 AV_WN32(dst + i * 4, offset_gu);

550 dst += p->linesize[0];

551 }

552 } else {

553 for (j = 0; j < avctx->height; j++) {

554 memset(dst, buf[1], avctx->width * planes);

555 dst += p->linesize[0];

556 }

557 }

558 break;

559 case FRAME_SOLID_COLOR:

560 if (avctx->bits_per_coded_sample == 24) {

561 avctx->pix_fmt = AV_PIX_FMT_RGB24;

562 } else {

563 avctx->pix_fmt = AV_PIX_FMT_RGB32;

564 offset_gu |= 0xFFU << 24;

565 }

566

567 if ((ret = ff_thread_get_buffer(avctx, &frame,0)) < 0)

568 return ret;

569

570 dst = p->data[0];

571 for (j = 0; j < avctx->height; j++) {

572 for (i = 0; i < avctx->width; i++)

573 if (avctx->bits_per_coded_sample == 24) {

574 AV_WB24(dst + i * 3, offset_gu);

575 } else {

576 AV_WN32(dst + i * 4, offset_gu);

577 }

578 dst += p->linesize[0];

579 }

580 break;

581 case FRAME_ARITH_RGBA:

582 avctx->pix_fmt = AV_PIX_FMT_RGB32;

583 planes = 4;

584 offset_ry += 4;

585 offs[3] = AV_RL32(buf + 9);

586 case FRAME_ARITH_RGB24:

587 case FRAME_U_RGB24:

588 if (frametype == FRAME_ARITH_RGB24 || frametype == FRAME_U_RGB24)

589 avctx->pix_fmt = AV_PIX_FMT_RGB24;

590

591 if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)

592 return ret;

593

594 offs[0] = offset_bv;

595 offs[1] = offset_gu;

596 offs[2] = offset_ry;

597

598 if (!l->rgb_planes) {

599 l->rgb_stride = FFALIGN(avctx->width, 16);

600 l->rgb_planes = av_malloc(l->rgb_stride * avctx->height * 4 + 16);

601 if (!l->rgb_planes) {

602 av_log(avctx, AV_LOG_ERROR, "cannot allocate temporary buffer\n");

603 return AVERROR(ENOMEM);

604 }

605 }

606 for (i = 0; i < planes; i++)

607 srcs[i] = l->rgb_planes + (i + 1) * l->rgb_stride * avctx->height - l->rgb_stride;

608 for (i = 0; i < planes; i++)

609 if (buf_size <= offs[i]) {

610 av_log(avctx, AV_LOG_ERROR,

611 "Invalid frame offsets\n");

612 return AVERROR_INVALIDDATA;

613 }

614

615 for (i = 0; i < planes; i++)

616 lag_decode_arith_plane(l, srcs[i],

617 avctx->width, avctx->height,

618 -l->rgb_stride, buf + offs[i],

619 buf_size - offs[i]);

620 dst = p->data[0];

621 for (i = 0; i < planes; i++)

622 srcs[i] = l->rgb_planes + i * l->rgb_stride * avctx->height;

623 for (j = 0; j < avctx->height; j++) {

624 for (i = 0; i < avctx->width; i++) {

625 uint8_t r, g, b, a;

626 r = srcs[0][i];

627 g = srcs[1][i];

628 b = srcs[2][i];

629 r += g;

630 b += g;

631 if (frametype == FRAME_ARITH_RGBA) {

632 a = srcs[3][i];

633 AV_WN32(dst + i * 4, MKBETAG(a, r, g, b));

634 } else {

635 dst[i * 3 + 0] = r;

636 dst[i * 3 + 1] = g;

637 dst[i * 3 + 2] = b;

638 }

639 }

640 dst += p->linesize[0];

641 for (i = 0; i < planes; i++)

642 srcs[i] += l->rgb_stride;

643 }

644 break;

645 case FRAME_ARITH_YUY2:

646 avctx->pix_fmt = AV_PIX_FMT_YUV422P;

647

648 if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)

649 return ret;

650

651 if (offset_ry >= buf_size ||

652 offset_gu >= buf_size ||

653 offset_bv >= buf_size) {

654 av_log(avctx, AV_LOG_ERROR,

655 "Invalid frame offsets\n");

656 return AVERROR_INVALIDDATA;

657 }

658

659 lag_decode_arith_plane(l, p->data[0], avctx->width, avctx->height,

660 p->linesize[0], buf + offset_ry,

661 buf_size - offset_ry);

662 lag_decode_arith_plane(l, p->data[1], avctx->width / 2,

663 avctx->height, p->linesize[1],

664 buf + offset_gu, buf_size - offset_gu);

665 lag_decode_arith_plane(l, p->data[2], avctx->width / 2,

666 avctx->height, p->linesize[2],

667 buf + offset_bv, buf_size - offset_bv);

668 break;

669 case FRAME_ARITH_YV12:

670 avctx->pix_fmt = AV_PIX_FMT_YUV420P;

671

672 if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)

673 return ret;

674 if (buf_size <= offset_ry || buf_size <= offset_gu || buf_size <= offset_bv) {

675 return AVERROR_INVALIDDATA;

676 }

677

678 if (offset_ry >= buf_size ||

679 offset_gu >= buf_size ||

680 offset_bv >= buf_size) {

681 av_log(avctx, AV_LOG_ERROR,

682 "Invalid frame offsets\n");

683 return AVERROR_INVALIDDATA;

684 }

685

686 lag_decode_arith_plane(l, p->data[0], avctx->width, avctx->height,

687 p->linesize[0], buf + offset_ry,

688 buf_size - offset_ry);

689 lag_decode_arith_plane(l, p->data[2], avctx->width / 2,

690 avctx->height / 2, p->linesize[2],

691 buf + offset_gu, buf_size - offset_gu);

692 lag_decode_arith_plane(l, p->data[1], avctx->width / 2,

693 avctx->height / 2, p->linesize[1],

694 buf + offset_bv, buf_size - offset_bv);

695 break;

696 default:

697 av_log(avctx, AV_LOG_ERROR,

698 "Unsupported Lagarith frame type: %#x\n", frametype);

699 return AVERROR_PATCHWELCOME;

700 }

701

702 *got_frame = 1;

703

704 return buf_size;

705 }

706

707 static av_cold int lag_decode_init(AVCodecContext *avctx)

708 {

709 LagarithContext *l = avctx->priv_data;

710 l->avctx = avctx;

711

712 ff_dsputil_init(&l->dsp, avctx);

713

714 return 0;

715 }

716

717 static av_cold int lag_decode_end(AVCodecContext *avctx)

718 {

719 LagarithContext *l = avctx->priv_data;

720

721 av_freep(&l->rgb_planes);

722

723 return 0;

724 }

725

726 AVCodec ff_lagarith_decoder = {

727 .name = "lagarith",

728 .type = AVMEDIA_TYPE_VIDEO,

729 .id = AV_CODEC_ID_LAGARITH,

730 .priv_data_size = sizeof(LagarithContext),

731 .init = lag_decode_init,

732 .close = lag_decode_end,

733 .decode = lag_decode_frame,

734 .capabilities = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,

735 .long_name = NULL_IF_CONFIG_SMALL("Lagarith lossless"),

736 };

Generated on Wed Jul 10 2013 23:48:00 for FFmpeg by doxygen 1.8.2