FFmpeg: libavcodec/g2meet.c Source File

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g2meet.c

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1 /*

2 * Go2Webinar 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 * Go2Webinar decoder

25 */

27 #include <zlib.h>

29 #include "libavutil/intreadwrite.h"

30 #include "avcodec.h"

31 #include "bytestream.h"

32 #include "dsputil.h"

33 #include "get_bits.h"

34 #include "internal.h"

35 #include "mjpeg.h"

37 enum ChunkType {

38 FRAME_INFO = 0xC8,

39 TILE_DATA,

40 CURSOR_POS,

41 CURSOR_SHAPE,

42 CHUNK_CC,

43 CHUNK_CD

44 };

46 enum Compression {

47 COMPR_EPIC_J_B = 2,

48 COMPR_KEMPF_J_B,

49 };

51 static const uint8_t luma_quant[64] = {

52 8, 6, 5, 8, 12, 20, 26, 31,

53 6, 6, 7, 10, 13, 29, 30, 28,

54 7, 7, 8, 12, 20, 29, 35, 28,

55 7, 9, 11, 15, 26, 44, 40, 31,

56 9, 11, 19, 28, 34, 55, 52, 39,

57 12, 18, 28, 32, 41, 52, 57, 46,

58 25, 32, 39, 44, 52, 61, 60, 51,

59 36, 46, 48, 49, 56, 50, 52, 50

60 };

62 static const uint8_t chroma_quant[64] = {

63 9, 9, 12, 24, 50, 50, 50, 50,

64 9, 11, 13, 33, 50, 50, 50, 50,

65 12, 13, 28, 50, 50, 50, 50, 50,

66 24, 33, 50, 50, 50, 50, 50, 50,

67 50, 50, 50, 50, 50, 50, 50, 50,

68 50, 50, 50, 50, 50, 50, 50, 50,

69 50, 50, 50, 50, 50, 50, 50, 50,

70 50, 50, 50, 50, 50, 50, 50, 50,

71 };

73 typedef struct JPGContext {

74 DSPContext dsp;

75 ScanTable scantable;

77 VLC dc_vlc[2], ac_vlc[2];

78 int prev_dc[3];

79 DECLARE_ALIGNED(16, int16_t, block)[6][64];

81 uint8_t *buf;

82 } JPGContext;

84 typedef struct G2MContext {

85 JPGContext jc;

86 int version;

88 int compression;

89 int width, height, bpp;

90 int tile_width, tile_height;

91 int tiles_x, tiles_y, tile_x, tile_y;

93 int got_header;

95 uint8_t *framebuf;

96 int framebuf_stride, old_width, old_height;

98 uint8_t *synth_tile, *jpeg_tile;

99 int tile_stride, old_tile_w, old_tile_h;

100

101 uint8_t *kempf_buf, *kempf_flags;

102

103 uint8_t *cursor;

104 int cursor_stride;

105 int cursor_fmt;

106 int cursor_w, cursor_h, cursor_x, cursor_y;

107 int cursor_hot_x, cursor_hot_y;

108 } G2MContext;

109

110 static av_cold int build_vlc(VLC *vlc, const uint8_t *bits_table,

111 const uint8_t *val_table, int nb_codes,

112 int is_ac)

113 {

114 uint8_t huff_size[256] = { 0 };

115 uint16_t huff_code[256];

116 uint16_t huff_sym[256];

117 int i;

118

119 ff_mjpeg_build_huffman_codes(huff_size, huff_code, bits_table, val_table);

120

121 for (i = 0; i < 256; i++)

122 huff_sym[i] = i + 16 * is_ac;

123

124 if (is_ac)

125 huff_sym[0] = 16 * 256;

126

127 return ff_init_vlc_sparse(vlc, 9, nb_codes, huff_size, 1, 1,

128 huff_code, 2, 2, huff_sym, 2, 2, 0);

129 }

130

131 static av_cold int jpg_init(AVCodecContext *avctx, JPGContext *c)

132 {

133 int ret;

134

135 ret = build_vlc(&c->dc_vlc[0], avpriv_mjpeg_bits_dc_luminance,

136 avpriv_mjpeg_val_dc, 12, 0);

137 if (ret)

138 return ret;

139 ret = build_vlc(&c->dc_vlc[1], avpriv_mjpeg_bits_dc_chrominance,

140 avpriv_mjpeg_val_dc, 12, 0);

141 if (ret)

142 return ret;

143 ret = build_vlc(&c->ac_vlc[0], avpriv_mjpeg_bits_ac_luminance,

144 avpriv_mjpeg_val_ac_luminance, 251, 1);

145 if (ret)

146 return ret;

147 ret = build_vlc(&c->ac_vlc[1], avpriv_mjpeg_bits_ac_chrominance,

148 avpriv_mjpeg_val_ac_chrominance, 251, 1);

149 if (ret)

150 return ret;

151

152 ff_dsputil_init(&c->dsp, avctx);

153 ff_init_scantable(c->dsp.idct_permutation, &c->scantable,

154 ff_zigzag_direct);

155

156 return 0;

157 }

158

159 static av_cold void jpg_free_context(JPGContext *ctx)

160 {

161 int i;

162

163 for (i = 0; i < 2; i++) {

164 ff_free_vlc(&ctx->dc_vlc[i]);

165 ff_free_vlc(&ctx->ac_vlc[i]);

166 }

167

168 av_freep(&ctx->buf);

169 }

170

171 static void jpg_unescape(const uint8_t *src, int src_size,

172 uint8_t *dst, int *dst_size)

173 {

174 const uint8_t *src_end = src + src_size;

175 uint8_t *dst_start = dst;

176

177 while (src < src_end) {

178 uint8_t x = *src++;

179

180 *dst++ = x;

181

182 if (x == 0xFF && !*src)

183 src++;

184 }

185 *dst_size = dst - dst_start;

186 }

187

188 static int jpg_decode_block(JPGContext *c, GetBitContext *gb,

189 int plane, int16_t *block)

190 {

191 int dc, val, pos;

192 const int is_chroma = !!plane;

193 const uint8_t *qmat = is_chroma ? chroma_quant : luma_quant;

194

195 c->dsp.clear_block(block);

196 dc = get_vlc2(gb, c->dc_vlc[is_chroma].table, 9, 3);

197 if (dc < 0)

198 return AVERROR_INVALIDDATA;

199 if (dc)

200 dc = get_xbits(gb, dc);

201 dc = dc * qmat[0] + c->prev_dc[plane];

202 block[0] = dc;

203 c->prev_dc[plane] = dc;

204

205 pos = 0;

206 while (pos < 63) {

207 val = get_vlc2(gb, c->ac_vlc[is_chroma].table, 9, 3);

208 if (val < 0)

209 return AVERROR_INVALIDDATA;

210 pos += val >> 4;

211 val &= 0xF;

212 if (pos > 63)

213 return val ? AVERROR_INVALIDDATA : 0;

214 if (val) {

215 int nbits = val;

216

217 val = get_xbits(gb, nbits);

218 val *= qmat[ff_zigzag_direct[pos]];

219 block[c->scantable.permutated[pos]] = val;

220 }

221 }

222 return 0;

223 }

224

225 static inline void yuv2rgb(uint8_t *out, int Y, int U, int V)

226 {

227 out[0] = av_clip_uint8(Y + ( 91881 * V + 32768 >> 16));

228 out[1] = av_clip_uint8(Y + (-22554 * U - 46802 * V + 32768 >> 16));

229 out[2] = av_clip_uint8(Y + (116130 * U + 32768 >> 16));

230 }

231

232 static int jpg_decode_data(JPGContext *c, int width, int height,

233 const uint8_t *src, int src_size,

234 uint8_t *dst, int dst_stride,

235 const uint8_t *mask, int mask_stride, int num_mbs,

236 int swapuv)

237 {

238 GetBitContext gb;

239 uint8_t *tmp;

240 int mb_w, mb_h, mb_x, mb_y, i, j;

241 int bx, by;

242 int unesc_size;

243 int ret;

244

245 tmp = av_realloc(c->buf, src_size + FF_INPUT_BUFFER_PADDING_SIZE);

246 if (!tmp)

247 return AVERROR(ENOMEM);

248 c->buf = tmp;

249 jpg_unescape(src, src_size, c->buf, &unesc_size);

250 memset(c->buf + unesc_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);

251 init_get_bits(&gb, c->buf, unesc_size * 8);

252

253 width = FFALIGN(width, 16);

254 mb_w = width >> 4;

255 mb_h = (height + 15) >> 4;

256

257 if (!num_mbs)

258 num_mbs = mb_w * mb_h;

259

260 for (i = 0; i < 3; i++)

261 c->prev_dc[i] = 1024;

262 bx = by = 0;

263 for (mb_y = 0; mb_y < mb_h; mb_y++) {

264 for (mb_x = 0; mb_x < mb_w; mb_x++) {

265 if (mask && !mask[mb_x]) {

266 bx += 16;

267 continue;

268 }

269 for (j = 0; j < 2; j++) {

270 for (i = 0; i < 2; i++) {

271 if ((ret = jpg_decode_block(c, &gb, 0,

272 c->block[i + j * 2])) != 0)

273 return ret;

274 c->dsp.idct(c->block[i + j * 2]);

275 }

276 }

277 for (i = 1; i < 3; i++) {

278 if ((ret = jpg_decode_block(c, &gb, i, c->block[i + 3])) != 0)

279 return ret;

280 c->dsp.idct(c->block[i + 3]);

281 }

282

283 for (j = 0; j < 16; j++) {

284 uint8_t *out = dst + bx * 3 + (by + j) * dst_stride;

285 for (i = 0; i < 16; i++) {

286 int Y, U, V;

287

288 Y = c->block[(j >> 3) * 2 + (i >> 3)][(i & 7) + (j & 7) * 8];

289 U = c->block[4 ^ swapuv][(i >> 1) + (j >> 1) * 8] - 128;

290 V = c->block[5 ^ swapuv][(i >> 1) + (j >> 1) * 8] - 128;

291 yuv2rgb(out + i * 3, Y, U, V);

292 }

293 }

294

295 if (!--num_mbs)

296 return 0;

297 bx += 16;

298 }

299 bx = 0;

300 by += 16;

301 if (mask)

302 mask += mask_stride;

303 }

304

305 return 0;

306 }

307

308 static void kempf_restore_buf(const uint8_t *src, int len,

309 uint8_t *dst, int stride,

310 const uint8_t *jpeg_tile, int tile_stride,

311 int width, int height,

312 const uint8_t *pal, int npal, int tidx)

313 {

314 GetBitContext gb;

315 int i, j, nb, col;

316

317 init_get_bits(&gb, src, len * 8);

318

319 if (npal <= 2) nb = 1;

320 else if (npal <= 4) nb = 2;

321 else if (npal <= 16) nb = 4;

322 else nb = 8;

323

324 for (j = 0; j < height; j++, dst += stride, jpeg_tile += tile_stride) {

325 if (get_bits(&gb, 8))

326 continue;

327 for (i = 0; i < width; i++) {

328 col = get_bits(&gb, nb);

329 if (col != tidx)

330 memcpy(dst + i * 3, pal + col * 3, 3);

331 else

332 memcpy(dst + i * 3, jpeg_tile + i * 3, 3);

333 }

334 }

335 }

336

337 static int kempf_decode_tile(G2MContext *c, int tile_x, int tile_y,

338 const uint8_t *src, int src_size)

339 {

340 int width, height;

341 int hdr, zsize, npal, tidx = -1, ret;

342 int i, j;

343 const uint8_t *src_end = src + src_size;

344 uint8_t pal[768], transp[3];

345 uLongf dlen = (c->tile_width + 1) * c->tile_height;

346 int sub_type;

347 int nblocks, cblocks, bstride;

348 int bits, bitbuf, coded;

349 uint8_t *dst = c->framebuf + tile_x * c->tile_width * 3 +

350 tile_y * c->tile_height * c->framebuf_stride;

351

352 if (src_size < 2)

353 return AVERROR_INVALIDDATA;

354

355 width = FFMIN(c->width - tile_x * c->tile_width, c->tile_width);

356 height = FFMIN(c->height - tile_y * c->tile_height, c->tile_height);

357

358 hdr = *src++;

359 sub_type = hdr >> 5;

360 if (sub_type == 0) {

361 int j;

362 memcpy(transp, src, 3);

363 src += 3;

364 for (j = 0; j < height; j++, dst += c->framebuf_stride)

365 for (i = 0; i < width; i++)

366 memcpy(dst + i * 3, transp, 3);

367 return 0;

368 } else if (sub_type == 1) {

369 return jpg_decode_data(&c->jc, width, height, src, src_end - src,

370 dst, c->framebuf_stride, NULL, 0, 0, 0);

371 }

372

373 if (sub_type != 2) {

374 memcpy(transp, src, 3);

375 src += 3;

376 }

377 npal = *src++ + 1;

378 memcpy(pal, src, npal * 3); src += npal * 3;

379 if (sub_type != 2) {

380 for (i = 0; i < npal; i++) {

381 if (!memcmp(pal + i * 3, transp, 3)) {

382 tidx = i;

383 break;

384 }

385 }

386 }

387

388 if (src_end - src < 2)

389 return 0;

390 zsize = (src[0] << 8) | src[1]; src += 2;

391

392 if (src_end - src < zsize)

393 return AVERROR_INVALIDDATA;

394

395 ret = uncompress(c->kempf_buf, &dlen, src, zsize);

396 if (ret)

397 return AVERROR_INVALIDDATA;

398 src += zsize;

399

400 if (sub_type == 2) {

401 kempf_restore_buf(c->kempf_buf, dlen, dst, c->framebuf_stride,

402 NULL, 0, width, height, pal, npal, tidx);

403 return 0;

404 }

405

406 nblocks = *src++ + 1;

407 cblocks = 0;

408 bstride = FFALIGN(width, 16) >> 4;

409 // blocks are coded LSB and we need normal bitreader for JPEG data

410 bits = 0;

411 for (i = 0; i < (FFALIGN(height, 16) >> 4); i++) {

412 for (j = 0; j < (FFALIGN(width, 16) >> 4); j++) {

413 if (!bits) {

414 bitbuf = *src++;

415 bits = 8;

416 }

417 coded = bitbuf & 1;

418 bits--;

419 bitbuf >>= 1;

420 cblocks += coded;

421 if (cblocks > nblocks)

422 return AVERROR_INVALIDDATA;

423 c->kempf_flags[j + i * bstride] = coded;

424 }

425 }

426

427 memset(c->jpeg_tile, 0, c->tile_stride * height);

428 jpg_decode_data(&c->jc, width, height, src, src_end - src,

429 c->jpeg_tile, c->tile_stride,

430 c->kempf_flags, bstride, nblocks, 0);

431

432 kempf_restore_buf(c->kempf_buf, dlen, dst, c->framebuf_stride,

433 c->jpeg_tile, c->tile_stride,

434 width, height, pal, npal, tidx);

435

436 return 0;

437 }

438

439 static int g2m_init_buffers(G2MContext *c)

440 {

441 int aligned_height;

442

443 if (!c->framebuf || c->old_width < c->width || c->old_height < c->height) {

444 c->framebuf_stride = FFALIGN(c->width * 3, 16);

445 aligned_height = FFALIGN(c->height, 16);

446 av_free(c->framebuf);

447 c->framebuf = av_mallocz(c->framebuf_stride * aligned_height);

448 if (!c->framebuf)

449 return AVERROR(ENOMEM);

450 }

451 if (!c->synth_tile || !c->jpeg_tile ||

452 c->old_tile_w < c->tile_width ||

453 c->old_tile_h < c->tile_height) {

454 c->tile_stride = FFALIGN(c->tile_width * 3, 16);

455 aligned_height = FFALIGN(c->tile_height, 16);

456 av_free(c->synth_tile);

457 av_free(c->jpeg_tile);

458 av_free(c->kempf_buf);

459 av_free(c->kempf_flags);

460 c->synth_tile = av_mallocz(c->tile_stride * aligned_height);

461 c->jpeg_tile = av_mallocz(c->tile_stride * aligned_height);

462 c->kempf_buf = av_mallocz((c->tile_width + 1) * aligned_height

463 + FF_INPUT_BUFFER_PADDING_SIZE);

464 c->kempf_flags = av_mallocz( c->tile_width * aligned_height);

465 if (!c->synth_tile || !c->jpeg_tile ||

466 !c->kempf_buf || !c->kempf_flags)

467 return AVERROR(ENOMEM);

468 }

469

470 return 0;

471 }

472

473 static int g2m_load_cursor(AVCodecContext *avctx, G2MContext *c,

474 GetByteContext *gb)

475 {

476 int i, j, k;

477 uint8_t *dst;

478 uint32_t bits;

479 uint32_t cur_size, cursor_w, cursor_h, cursor_stride;

480 uint32_t cursor_hot_x, cursor_hot_y;

481 int cursor_fmt;

482 uint8_t *tmp;

483

484 cur_size = bytestream2_get_be32(gb);

485 cursor_w = bytestream2_get_byte(gb);

486 cursor_h = bytestream2_get_byte(gb);

487 cursor_hot_x = bytestream2_get_byte(gb);

488 cursor_hot_y = bytestream2_get_byte(gb);

489 cursor_fmt = bytestream2_get_byte(gb);

490

491 cursor_stride = cursor_w * 4;

492

493 if (cursor_w < 1 || cursor_w > 256 ||

494 cursor_h < 1 || cursor_h > 256) {

495 av_log(avctx, AV_LOG_ERROR, "Invalid cursor dimensions %dx%d\n",

496 cursor_w, cursor_h);

497 return AVERROR_INVALIDDATA;

498 }

499 if (cursor_hot_x > cursor_w || cursor_hot_y > cursor_h) {

500 av_log(avctx, AV_LOG_WARNING, "Invalid hotspot position %d,%d\n",

501 cursor_hot_x, cursor_hot_y);

502 cursor_hot_x = FFMIN(cursor_hot_x, cursor_w - 1);

503 cursor_hot_y = FFMIN(cursor_hot_y, cursor_h - 1);

504 }

505 if (cur_size - 9 > bytestream2_get_bytes_left(gb) ||

506 c->cursor_w * c->cursor_h / 4 > cur_size) {

507 av_log(avctx, AV_LOG_ERROR, "Invalid cursor data size %d/%d\n",

508 cur_size, bytestream2_get_bytes_left(gb));

509 return AVERROR_INVALIDDATA;

510 }

511 if (cursor_fmt != 1 && cursor_fmt != 32) {

512 avpriv_report_missing_feature(avctx, "Cursor format %d",

513 cursor_fmt);

514 return AVERROR_PATCHWELCOME;

515 }

516

517 if (cursor_fmt == 1 && cursor_w % 32) {

518 avpriv_report_missing_feature(avctx, "odd monochrome cursor width %d", cursor_w);

519 return AVERROR_PATCHWELCOME;

520 }

521

522 tmp = av_realloc(c->cursor, cursor_stride * cursor_h);

523 if (!tmp) {

524 av_log(avctx, AV_LOG_ERROR, "Cannot allocate cursor buffer\n");

525 return AVERROR(ENOMEM);

526 }

527

528 c->cursor = tmp;

529 c->cursor_w = cursor_w;

530 c->cursor_h = cursor_h;

531 c->cursor_hot_x = cursor_hot_x;

532 c->cursor_hot_y = cursor_hot_y;

533 c->cursor_fmt = cursor_fmt;

534 c->cursor_stride = cursor_stride;

535

536 dst = c->cursor;

537 switch (c->cursor_fmt) {

538 case 1: // old monochrome

539 for (j = 0; j < c->cursor_h; j++) {

540 for (i = 0; i < c->cursor_w; i += 32) {

541 bits = bytestream2_get_be32(gb);

542 for (k = 0; k < 32; k++) {

543 dst[0] = !!(bits & 0x80000000);

544 dst += 4;

545 bits <<= 1;

546 }

547 }

548 }

549

550 dst = c->cursor;

551 for (j = 0; j < c->cursor_h; j++) {

552 for (i = 0; i < c->cursor_w; i += 32) {

553 bits = bytestream2_get_be32(gb);

554 for (k = 0; k < 32; k++) {

555 int mask_bit = !!(bits & 0x80000000);

556 switch (dst[0] * 2 + mask_bit) {

557 case 0:

558 dst[0] = 0xFF; dst[1] = 0x00;

559 dst[2] = 0x00; dst[3] = 0x00;

560 break;

561 case 1:

562 dst[0] = 0xFF; dst[1] = 0xFF;

563 dst[2] = 0xFF; dst[3] = 0xFF;

564 break;

565 default:

566 dst[0] = 0x00; dst[1] = 0x00;

567 dst[2] = 0x00; dst[3] = 0x00;

568 }

569 dst += 4;

570 bits <<= 1;

571 }

572 }

573 }

574 break;

575 case 32: // full colour

576 /* skip monochrome version of the cursor and decode RGBA instead */

577 bytestream2_skip(gb, c->cursor_h * (FFALIGN(c->cursor_w, 32) >> 3));

578 for (j = 0; j < c->cursor_h; j++) {

579 for (i = 0; i < c->cursor_w; i++) {

580 int val = bytestream2_get_be32(gb);

581 *dst++ = val >> 0;

582 *dst++ = val >> 8;

583 *dst++ = val >> 16;

584 *dst++ = val >> 24;

585 }

586 }

587 break;

588 default:

589 return AVERROR_PATCHWELCOME;

590 }

591 return 0;

592 }

593

594 #define APPLY_ALPHA(src, new, alpha) \

595 src = (src * (256 - alpha) + new * alpha) >> 8

596

597 static void g2m_paint_cursor(G2MContext *c, uint8_t *dst, int stride)

598 {

599 int i, j;

600 int x, y, w, h;

601 const uint8_t *cursor;

602

603 if (!c->cursor)

604 return;

605

606 x = c->cursor_x - c->cursor_hot_x;

607 y = c->cursor_y - c->cursor_hot_y;

608

609 cursor = c->cursor;

610 w = c->cursor_w;

611 h = c->cursor_h;

612

613 if (x + w > c->width)

614 w = c->width - x;

615 if (y + h > c->height)

616 h = c->height - y;

617 if (x < 0) {

618 w += x;

619 cursor += -x * 4;

620 } else {

621 dst += x * 3;

622 }

623 if (y < 0) {

624 h += y;

625 cursor += -y * c->cursor_stride;

626 } else {

627 dst += y * stride;

628 }

629 if (w < 0 || h < 0)

630 return;

631

632 for (j = 0; j < h; j++) {

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

634 uint8_t alpha = cursor[i * 4];

635 APPLY_ALPHA(dst[i * 3 + 0], cursor[i * 4 + 1], alpha);

636 APPLY_ALPHA(dst[i * 3 + 1], cursor[i * 4 + 2], alpha);

637 APPLY_ALPHA(dst[i * 3 + 2], cursor[i * 4 + 3], alpha);

638 }

639 dst += stride;

640 cursor += c->cursor_stride;

641 }

642 }

643

644 static int g2m_decode_frame(AVCodecContext *avctx, void *data,

645 int *got_picture_ptr, AVPacket *avpkt)

646 {

647 const uint8_t *buf = avpkt->data;

648 int buf_size = avpkt->size;

649 G2MContext *c = avctx->priv_data;

650 AVFrame *pic = data;

651 GetByteContext bc, tbc;

652 int magic;

653 int got_header = 0;

654 uint32_t chunk_size;

655 int chunk_type;

656 int i;

657 int ret;

658

659 if (buf_size < 12) {

660 av_log(avctx, AV_LOG_ERROR,

661 "Frame should have at least 12 bytes, got %d instead\n",

662 buf_size);

663 return AVERROR_INVALIDDATA;

664 }

665

666 bytestream2_init(&bc, buf, buf_size);

667

668 magic = bytestream2_get_be32(&bc);

669 if ((magic & ~0xF) != MKBETAG('G', '2', 'M', '0') ||

670 (magic & 0xF) < 2 || (magic & 0xF) > 4) {

671 av_log(avctx, AV_LOG_ERROR, "Wrong magic %08X\n", magic);

672 return AVERROR_INVALIDDATA;

673 }

674

675 if ((magic & 0xF) != 4) {

676 av_log(avctx, AV_LOG_ERROR, "G2M2 and G2M3 are not yet supported\n");

677 return AVERROR(ENOSYS);

678 }

679

680 while (bytestream2_get_bytes_left(&bc) > 5) {

681 chunk_size = bytestream2_get_le32(&bc) - 1;

682 chunk_type = bytestream2_get_byte(&bc);

683 if (chunk_size > bytestream2_get_bytes_left(&bc)) {

684 av_log(avctx, AV_LOG_ERROR, "Invalid chunk size %d type %02X\n",

685 chunk_size, chunk_type);

686 break;

687 }

688 switch (chunk_type) {

689 case FRAME_INFO:

690 c->got_header = 0;

691 if (chunk_size < 21) {

692 av_log(avctx, AV_LOG_ERROR, "Invalid frame info size %d\n",

693 chunk_size);

694 break;

695 }

696 c->width = bytestream2_get_be32(&bc);

697 c->height = bytestream2_get_be32(&bc);

698 if (c->width < 16 || c->width > avctx->width ||

699 c->height < 16 || c->height > avctx->height) {

700 av_log(avctx, AV_LOG_ERROR,

701 "Invalid frame dimensions %dx%d\n",

702 c->width, c->height);

703 ret = AVERROR_INVALIDDATA;

704 goto header_fail;

705 }

706 if (c->width != avctx->width || c->height != avctx->height)

707 avcodec_set_dimensions(avctx, c->width, c->height);

708 c->compression = bytestream2_get_be32(&bc);

709 if (c->compression != 2 && c->compression != 3) {

710 av_log(avctx, AV_LOG_ERROR,

711 "Unknown compression method %d\n",

712 c->compression);

713 return AVERROR_PATCHWELCOME;

714 }

715 c->tile_width = bytestream2_get_be32(&bc);

716 c->tile_height = bytestream2_get_be32(&bc);

717 if (!c->tile_width || !c->tile_height) {

718 av_log(avctx, AV_LOG_ERROR,

719 "Invalid tile dimensions %dx%d\n",

720 c->tile_width, c->tile_height);

721 ret = AVERROR_INVALIDDATA;

722 goto header_fail;

723 }

724 c->tiles_x = (c->width + c->tile_width - 1) / c->tile_width;

725 c->tiles_y = (c->height + c->tile_height - 1) / c->tile_height;

726 c->bpp = bytestream2_get_byte(&bc);

727 chunk_size -= 21;

728 bytestream2_skip(&bc, chunk_size);

729 if (g2m_init_buffers(c)) {

730 ret = AVERROR(ENOMEM);

731 goto header_fail;

732 }

733 got_header = 1;

734 break;

735 case TILE_DATA:

736 if (!c->tiles_x || !c->tiles_y) {

737 av_log(avctx, AV_LOG_WARNING,

738 "No frame header - skipping tile\n");

739 bytestream2_skip(&bc, bytestream2_get_bytes_left(&bc));

740 break;

741 }

742 if (chunk_size < 2) {

743 av_log(avctx, AV_LOG_ERROR, "Invalid tile data size %d\n",

744 chunk_size);

745 break;

746 }

747 c->tile_x = bytestream2_get_byte(&bc);

748 c->tile_y = bytestream2_get_byte(&bc);

749 if (c->tile_x >= c->tiles_x || c->tile_y >= c->tiles_y) {

750 av_log(avctx, AV_LOG_ERROR,

751 "Invalid tile pos %d,%d (in %dx%d grid)\n",

752 c->tile_x, c->tile_y, c->tiles_x, c->tiles_y);

753 break;

754 }

755 chunk_size -= 2;

756 ret = 0;

757 switch (c->compression) {

758 case COMPR_EPIC_J_B:

759 av_log(avctx, AV_LOG_ERROR,

760 "ePIC j-b compression is not implemented yet\n");

761 return AVERROR(ENOSYS);

762 case COMPR_KEMPF_J_B:

763 ret = kempf_decode_tile(c, c->tile_x, c->tile_y,

764 buf + bytestream2_tell(&bc),

765 chunk_size);

766 break;

767 }

768 if (ret && c->framebuf)

769 av_log(avctx, AV_LOG_ERROR, "Error decoding tile %d,%d\n",

770 c->tile_x, c->tile_y);

771 bytestream2_skip(&bc, chunk_size);

772 break;

773 case CURSOR_POS:

774 if (chunk_size < 5) {

775 av_log(avctx, AV_LOG_ERROR, "Invalid cursor pos size %d\n",

776 chunk_size);

777 break;

778 }

779 c->cursor_x = bytestream2_get_be16(&bc);

780 c->cursor_y = bytestream2_get_be16(&bc);

781 bytestream2_skip(&bc, chunk_size - 4);

782 break;

783 case CURSOR_SHAPE:

784 if (chunk_size < 8) {

785 av_log(avctx, AV_LOG_ERROR, "Invalid cursor data size %d\n",

786 chunk_size);

787 break;

788 }

789 bytestream2_init(&tbc, buf + bytestream2_tell(&bc),

790 chunk_size - 4);

791 g2m_load_cursor(avctx, c, &tbc);

792 bytestream2_skip(&bc, chunk_size);

793 break;

794 case CHUNK_CC:

795 case CHUNK_CD:

796 bytestream2_skip(&bc, chunk_size);

797 break;

798 default:

799 av_log(avctx, AV_LOG_WARNING, "Skipping chunk type %02X\n",

800 chunk_type);

801 bytestream2_skip(&bc, chunk_size);

802 }

803 }

804 if (got_header)

805 c->got_header = 1;

806

807 if (c->width && c->height && c->framebuf) {

808 if ((ret = ff_get_buffer(avctx, pic, 0)) < 0) {

809 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");

810 return ret;

811 }

812

813 pic->key_frame = got_header;

814 pic->pict_type = got_header ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;

815

816 for (i = 0; i < avctx->height; i++)

817 memcpy(pic->data[0] + i * pic->linesize[0],

818 c->framebuf + i * c->framebuf_stride,

819 c->width * 3);

820 g2m_paint_cursor(c, pic->data[0], pic->linesize[0]);

821

822 *got_picture_ptr = 1;

823 }

824

825 return buf_size;

826 header_fail:

827 c->width = c->height = 0;

828 c->tiles_x = c->tiles_y = 0;

829 return ret;

830 }

831

832 static av_cold int g2m_decode_init(AVCodecContext *avctx)

833 {

834 G2MContext * const c = avctx->priv_data;

835 int ret;

836

837 if ((ret = jpg_init(avctx, &c->jc)) != 0) {

838 av_log(avctx, AV_LOG_ERROR, "Cannot initialise VLCs\n");

839 jpg_free_context(&c->jc);

840 return AVERROR(ENOMEM);

841 }

842

843 avctx->pix_fmt = AV_PIX_FMT_RGB24;

844

845 return 0;

846 }

847

848 static av_cold int g2m_decode_end(AVCodecContext *avctx)

849 {

850 G2MContext * const c = avctx->priv_data;

851

852 jpg_free_context(&c->jc);

853

854 av_freep(&c->kempf_buf);

855 av_freep(&c->kempf_flags);

856 av_freep(&c->synth_tile);

857 av_freep(&c->jpeg_tile);

858 av_freep(&c->cursor);

859 av_freep(&c->framebuf);

860

861 return 0;

862 }

863

864 AVCodec ff_g2m_decoder = {

865 .name = "g2m",

866 .long_name = NULL_IF_CONFIG_SMALL("Go2Meeting"),

867 .type = AVMEDIA_TYPE_VIDEO,

868 .id = AV_CODEC_ID_G2M,

869 .priv_data_size = sizeof(G2MContext),

870 .init = g2m_decode_init,

871 .close = g2m_decode_end,

872 .decode = g2m_decode_frame,

873 .capabilities = CODEC_CAP_DR1,

874 };

Generated on Wed Jul 10 2013 23:47:58 for FFmpeg by doxygen 1.8.2