FFmpeg: libavcodec/flashsv.c Source File

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libavcodec

flashsv.c

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1 /*

2 * Flash Screen Video 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 * Flash Screen Video decoder

26 * @author Alex Beregszaszi

27 * @author Benjamin Larsson

28 * @author Daniel Verkamp

29 * @author Konstantin Shishkov

30 *

31 * A description of the bitstream format for Flash Screen Video version 1/2

32 * is part of the SWF File Format Specification (version 10), which can be

33 * downloaded from http://www.adobe.com/devnet/swf.html.

34 */

36 #include <stdio.h>

37 #include <stdlib.h>

38 #include <zlib.h>

40 #include "libavutil/intreadwrite.h"

41 #include "avcodec.h"

42 #include "bytestream.h"

43 #include "get_bits.h"

44 #include "internal.h"

46 typedef struct BlockInfo {

47 uint8_t *pos;

48 int size;

49 } BlockInfo;

51 typedef struct FlashSVContext {

52 AVCodecContext *avctx;

53 AVFrame *frame;

54 int image_width, image_height;

55 int block_width, block_height;

56 uint8_t *tmpblock;

57 int block_size;

58 z_stream zstream;

59 int ver;

60 const uint32_t *pal;

61 int is_keyframe;

62 uint8_t *keyframedata;

63 uint8_t *keyframe;

64 BlockInfo *blocks;

65 uint8_t *deflate_block;

66 int deflate_block_size;

67 int color_depth;

68 int zlibprime_curr, zlibprime_prev;

69 int diff_start, diff_height;

70 } FlashSVContext;

72 static int decode_hybrid(const uint8_t *sptr, const uint8_t *sptr_end, uint8_t *dptr, int dx, int dy,

73 int h, int w, int stride, const uint32_t *pal)

74 {

75 int x, y;

76 const uint8_t *orig_src = sptr;

78 for (y = dx + h; y > dx; y--) {

79 uint8_t *dst = dptr + (y * stride) + dy * 3;

80 for (x = 0; x < w; x++) {

81 if (sptr >= sptr_end)

82 return AVERROR_INVALIDDATA;

83 if (*sptr & 0x80) {

84 /* 15-bit color */

85 unsigned c = AV_RB16(sptr) & ~0x8000;

86 unsigned b = c & 0x1F;

87 unsigned g = (c >> 5) & 0x1F;

88 unsigned r = c >> 10;

89 /* 000aaabb -> aaabbaaa */

90 *dst++ = (b << 3) | (b >> 2);

91 *dst++ = (g << 3) | (g >> 2);

92 *dst++ = (r << 3) | (r >> 2);

93 sptr += 2;

94 } else {

95 /* palette index */

96 uint32_t c = pal[*sptr++];

97 bytestream_put_le24(&dst, c);

98 }

99 }

100 }

101 return sptr - orig_src;

102 }

103

104 static av_cold int flashsv_decode_end(AVCodecContext *avctx)

105 {

106 FlashSVContext *s = avctx->priv_data;

107 inflateEnd(&s->zstream);

108 /* release the frame if needed */

109 av_frame_free(&s->frame);

110

111 /* free the tmpblock */

112 av_freep(&s->tmpblock);

113

114 return 0;

115 }

116

117 static av_cold int flashsv_decode_init(AVCodecContext *avctx)

118 {

119 FlashSVContext *s = avctx->priv_data;

120 int zret; // Zlib return code

121

122 s->avctx = avctx;

123 s->zstream.zalloc = Z_NULL;

124 s->zstream.zfree = Z_NULL;

125 s->zstream.opaque = Z_NULL;

126 zret = inflateInit(&s->zstream);

127 if (zret != Z_OK) {

128 av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);

129 return 1;

130 }

131 avctx->pix_fmt = AV_PIX_FMT_BGR24;

132

133 s->frame = av_frame_alloc();

134 if (!s->frame) {

135 flashsv_decode_end(avctx);

136 return AVERROR(ENOMEM);

137 }

138

139 return 0;

140 }

141

142 static int flashsv2_prime(FlashSVContext *s, uint8_t *src, int size)

143 {

144 z_stream zs;

145 int zret; // Zlib return code

146

147 if (!src)

148 return AVERROR_INVALIDDATA;

149

150 zs.zalloc = NULL;

151 zs.zfree = NULL;

152 zs.opaque = NULL;

153

154 s->zstream.next_in = src;

155 s->zstream.avail_in = size;

156 s->zstream.next_out = s->tmpblock;

157 s->zstream.avail_out = s->block_size * 3;

158 inflate(&s->zstream, Z_SYNC_FLUSH);

159

160 if (deflateInit(&zs, 0) != Z_OK)

161 return -1;

162 zs.next_in = s->tmpblock;

163 zs.avail_in = s->block_size * 3 - s->zstream.avail_out;

164 zs.next_out = s->deflate_block;

165 zs.avail_out = s->deflate_block_size;

166 deflate(&zs, Z_SYNC_FLUSH);

167 deflateEnd(&zs);

168

169 if ((zret = inflateReset(&s->zstream)) != Z_OK) {

170 av_log(s->avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);

171 return AVERROR_UNKNOWN;

172 }

173

174 s->zstream.next_in = s->deflate_block;

175 s->zstream.avail_in = s->deflate_block_size - zs.avail_out;

176 s->zstream.next_out = s->tmpblock;

177 s->zstream.avail_out = s->block_size * 3;

178 inflate(&s->zstream, Z_SYNC_FLUSH);

179

180 return 0;

181 }

182

183 static int flashsv_decode_block(AVCodecContext *avctx, AVPacket *avpkt,

184 GetBitContext *gb, int block_size,

185 int width, int height, int x_pos, int y_pos,

186 int blk_idx)

187 {

188 struct FlashSVContext *s = avctx->priv_data;

189 uint8_t *line = s->tmpblock;

190 int k;

191 int ret = inflateReset(&s->zstream);

192 if (ret != Z_OK) {

193 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);

194 return AVERROR_UNKNOWN;

195 }

196 if (s->zlibprime_curr || s->zlibprime_prev) {

197 ret = flashsv2_prime(s,

198 s->blocks[blk_idx].pos,

199 s->blocks[blk_idx].size);

200 if (ret < 0)

201 return ret;

202 }

203 s->zstream.next_in = avpkt->data + get_bits_count(gb) / 8;

204 s->zstream.avail_in = block_size;

205 s->zstream.next_out = s->tmpblock;

206 s->zstream.avail_out = s->block_size * 3;

207 ret = inflate(&s->zstream, Z_FINISH);

208 if (ret == Z_DATA_ERROR) {

209 av_log(avctx, AV_LOG_ERROR, "Zlib resync occurred\n");

210 inflateSync(&s->zstream);

211 ret = inflate(&s->zstream, Z_FINISH);

212 }

213

214 if (ret != Z_OK && ret != Z_STREAM_END) {

215 //return -1;

216 }

217

218 if (s->is_keyframe) {

219 s->blocks[blk_idx].pos = s->keyframedata + (get_bits_count(gb) / 8);

220 s->blocks[blk_idx].size = block_size;

221 }

222

223 y_pos += s->diff_start;

224

225 if (!s->color_depth) {

226 /* Flash Screen Video stores the image upside down, so copy

227 * lines to destination in reverse order. */

228 for (k = 1; k <= s->diff_height; k++) {

229 memcpy(s->frame->data[0] + x_pos * 3 +

230 (s->image_height - y_pos - k) * s->frame->linesize[0],

231 line, width * 3);

232 /* advance source pointer to next line */

233 line += width * 3;

234 }

235 } else {

236 /* hybrid 15-bit/palette mode */

237 ret = decode_hybrid(s->tmpblock, s->zstream.next_out,

238 s->frame->data[0],

239 s->image_height - (y_pos + 1 + s->diff_height),

240 x_pos, s->diff_height, width,

241 s->frame->linesize[0], s->pal);

242 if (ret < 0) {

243 av_log(avctx, AV_LOG_ERROR, "decode_hybrid failed\n");

244 return ret;

245 }

246 }

247 skip_bits_long(gb, 8 * block_size); /* skip the consumed bits */

248 return 0;

249 }

250

251 static int calc_deflate_block_size(int tmpblock_size)

252 {

253 z_stream zstream;

254 int size;

255

256 zstream.zalloc = Z_NULL;

257 zstream.zfree = Z_NULL;

258 zstream.opaque = Z_NULL;

259 if (deflateInit(&zstream, 0) != Z_OK)

260 return -1;

261 size = deflateBound(&zstream, tmpblock_size);

262 deflateEnd(&zstream);

263

264 return size;

265 }

266

267 static int flashsv_decode_frame(AVCodecContext *avctx, void *data,

268 int *got_frame, AVPacket *avpkt)

269 {

270 int buf_size = avpkt->size;

271 FlashSVContext *s = avctx->priv_data;

272 int h_blocks, v_blocks, h_part, v_part, i, j, ret;

273 GetBitContext gb;

274 int last_blockwidth = s->block_width;

275 int last_blockheight= s->block_height;

276

277 /* no supplementary picture */

278 if (buf_size == 0)

279 return 0;

280 if (buf_size < 4)

281 return -1;

282

283 if ((ret = init_get_bits8(&gb, avpkt->data, buf_size)) < 0)

284 return ret;

285

286 /* start to parse the bitstream */

287 s->block_width = 16 * (get_bits(&gb, 4) + 1);

288 s->image_width = get_bits(&gb, 12);

289 s->block_height = 16 * (get_bits(&gb, 4) + 1);

290 s->image_height = get_bits(&gb, 12);

291

292 if ( last_blockwidth != s->block_width

293 || last_blockheight!= s->block_height)

294 av_freep(&s->blocks);

295

296 if (s->ver == 2) {

297 skip_bits(&gb, 6);

298 if (get_bits1(&gb)) {

299 avpriv_request_sample(avctx, "iframe");

300 return AVERROR_PATCHWELCOME;

301 }

302 if (get_bits1(&gb)) {

303 avpriv_request_sample(avctx, "Custom palette");

304 return AVERROR_PATCHWELCOME;

305 }

306 }

307

308 /* calculate number of blocks and size of border (partial) blocks */

309 h_blocks = s->image_width / s->block_width;

310 h_part = s->image_width % s->block_width;

311 v_blocks = s->image_height / s->block_height;

312 v_part = s->image_height % s->block_height;

313

314 /* the block size could change between frames, make sure the buffer

315 * is large enough, if not, get a larger one */

316 if (s->block_size < s->block_width * s->block_height) {

317 int tmpblock_size = 3 * s->block_width * s->block_height, err;

318

319 if ((err = av_reallocp(&s->tmpblock, tmpblock_size)) < 0) {

320 s->block_size = 0;

321 av_log(avctx, AV_LOG_ERROR,

322 "Cannot allocate decompression buffer.\n");

323 return err;

324 }

325 if (s->ver == 2) {

326 s->deflate_block_size = calc_deflate_block_size(tmpblock_size);

327 if (s->deflate_block_size <= 0) {

328 av_log(avctx, AV_LOG_ERROR,

329 "Cannot determine deflate buffer size.\n");

330 return -1;

331 }

332 if ((err = av_reallocp(&s->deflate_block, s->deflate_block_size)) < 0) {

333 s->block_size = 0;

334 av_log(avctx, AV_LOG_ERROR, "Cannot allocate deflate buffer.\n");

335 return err;

336 }

337 }

338 }

339 s->block_size = s->block_width * s->block_height;

340

341 /* initialize the image size once */

342 if (avctx->width == 0 && avctx->height == 0) {

343 if ((ret = ff_set_dimensions(avctx, s->image_width, s->image_height)) < 0)

344 return ret;

345 }

346

347 /* check for changes of image width and image height */

348 if (avctx->width != s->image_width || avctx->height != s->image_height) {

349 av_log(avctx, AV_LOG_ERROR,

350 "Frame width or height differs from first frame!\n");

351 av_log(avctx, AV_LOG_ERROR, "fh = %d, fv %d vs ch = %d, cv = %d\n",

352 avctx->height, avctx->width, s->image_height, s->image_width);

353 return AVERROR_INVALIDDATA;

354 }

355

356 /* we care for keyframes only in Screen Video v2 */

357 s->is_keyframe = (avpkt->flags & AV_PKT_FLAG_KEY) && (s->ver == 2);

358 if (s->is_keyframe) {

359 int err;

360 if ((err = av_reallocp(&s->keyframedata, avpkt->size)) < 0)

361 return err;

362 memcpy(s->keyframedata, avpkt->data, avpkt->size);

363 }

364 if(s->ver == 2 && !s->blocks)

365 s->blocks = av_mallocz((v_blocks + !!v_part) * (h_blocks + !!h_part) *

366 sizeof(s->blocks[0]));

367

368 av_dlog(avctx, "image: %dx%d block: %dx%d num: %dx%d part: %dx%d\n",

369 s->image_width, s->image_height, s->block_width, s->block_height,

370 h_blocks, v_blocks, h_part, v_part);

371

372 if ((ret = ff_reget_buffer(avctx, s->frame)) < 0)

373 return ret;

374

375 /* loop over all block columns */

376 for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {

377

378 int y_pos = j * s->block_height; // vertical position in frame

379 int cur_blk_height = (j < v_blocks) ? s->block_height : v_part;

380

381 /* loop over all block rows */

382 for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {

383 int x_pos = i * s->block_width; // horizontal position in frame

384 int cur_blk_width = (i < h_blocks) ? s->block_width : h_part;

385 int has_diff = 0;

386

387 /* get the size of the compressed zlib chunk */

388 int size = get_bits(&gb, 16);

389

390 s->color_depth = 0;

391 s->zlibprime_curr = 0;

392 s->zlibprime_prev = 0;

393 s->diff_start = 0;

394 s->diff_height = cur_blk_height;

395

396 if (8 * size > get_bits_left(&gb)) {

397 av_frame_unref(s->frame);

398 return AVERROR_INVALIDDATA;

399 }

400

401 if (s->ver == 2 && size) {

402 skip_bits(&gb, 3);

403 s->color_depth = get_bits(&gb, 2);

404 has_diff = get_bits1(&gb);

405 s->zlibprime_curr = get_bits1(&gb);

406 s->zlibprime_prev = get_bits1(&gb);

407

408 if (s->color_depth != 0 && s->color_depth != 2) {

409 av_log(avctx, AV_LOG_ERROR,

410 "%dx%d invalid color depth %d\n",

411 i, j, s->color_depth);

412 return AVERROR_INVALIDDATA;

413 }

414

415 if (has_diff) {

416 if (!s->keyframe) {

417 av_log(avctx, AV_LOG_ERROR,

418 "Inter frame without keyframe\n");

419 return AVERROR_INVALIDDATA;

420 }

421 s->diff_start = get_bits(&gb, 8);

422 s->diff_height = get_bits(&gb, 8);

423 if (s->diff_start + s->diff_height > cur_blk_height) {

424 av_log(avctx, AV_LOG_ERROR,

425 "Block parameters invalid: %d + %d > %d\n",

426 s->diff_start, s->diff_height, cur_blk_height);

427 return AVERROR_INVALIDDATA;

428 }

429 av_log(avctx, AV_LOG_DEBUG,

430 "%dx%d diff start %d height %d\n",

431 i, j, s->diff_start, s->diff_height);

432 size -= 2;

433 }

434

435 if (s->zlibprime_prev)

436 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_prev\n", i, j);

437

438 if (s->zlibprime_curr) {

439 int col = get_bits(&gb, 8);

440 int row = get_bits(&gb, 8);

441 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_curr %dx%d\n",

442 i, j, col, row);

443 size -= 2;

444 avpriv_request_sample(avctx, "zlibprime_curr");

445 return AVERROR_PATCHWELCOME;

446 }

447 if (!s->blocks && (s->zlibprime_curr || s->zlibprime_prev)) {

448 av_log(avctx, AV_LOG_ERROR,

449 "no data available for zlib priming\n");

450 return AVERROR_INVALIDDATA;

451 }

452 size--; // account for flags byte

453 }

454

455 if (has_diff) {

456 int k;

457 int off = (s->image_height - y_pos - 1) * s->frame->linesize[0];

458

459 for (k = 0; k < cur_blk_height; k++) {

460 int x = off - k * s->frame->linesize[0] + x_pos * 3;

461 memcpy(s->frame->data[0] + x, s->keyframe + x,

462 cur_blk_width * 3);

463 }

464 }

465

466 /* skip unchanged blocks, which have size 0 */

467 if (size) {

468 if (flashsv_decode_block(avctx, avpkt, &gb, size,

469 cur_blk_width, cur_blk_height,

470 x_pos, y_pos,

471 i + j * (h_blocks + !!h_part)))

472 av_log(avctx, AV_LOG_ERROR,

473 "error in decompression of block %dx%d\n", i, j);

474 }

475 }

476 }

477 if (s->is_keyframe && s->ver == 2) {

478 if (!s->keyframe) {

479 s->keyframe = av_malloc(s->frame->linesize[0] * avctx->height);

480 if (!s->keyframe) {

481 av_log(avctx, AV_LOG_ERROR, "Cannot allocate image data\n");

482 return AVERROR(ENOMEM);

483 }

484 }

485 memcpy(s->keyframe, s->frame->data[0],

486 s->frame->linesize[0] * avctx->height);

487 }

488

489 if ((ret = av_frame_ref(data, s->frame)) < 0)

490 return ret;

491

492 *got_frame = 1;

493

494 if ((get_bits_count(&gb) / 8) != buf_size)

495 av_log(avctx, AV_LOG_ERROR, "buffer not fully consumed (%d != %d)\n",

496 buf_size, (get_bits_count(&gb) / 8));

497

498 /* report that the buffer was completely consumed */

499 return buf_size;

500 }

501

502 #if CONFIG_FLASHSV_DECODER

503 AVCodec ff_flashsv_decoder = {

504 .name = "flashsv",

505 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v1"),

506 .type = AVMEDIA_TYPE_VIDEO,

507 .id = AV_CODEC_ID_FLASHSV,

508 .priv_data_size = sizeof(FlashSVContext),

509 .init = flashsv_decode_init,

510 .close = flashsv_decode_end,

511 .decode = flashsv_decode_frame,

512 .capabilities = CODEC_CAP_DR1,

513 .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },

514 };

515 #endif /* CONFIG_FLASHSV_DECODER */

516

517 #if CONFIG_FLASHSV2_DECODER

518 static const uint32_t ff_flashsv2_default_palette[128] = {

519 0x000000, 0x333333, 0x666666, 0x999999, 0xCCCCCC, 0xFFFFFF,

520 0x330000, 0x660000, 0x990000, 0xCC0000, 0xFF0000, 0x003300,

521 0x006600, 0x009900, 0x00CC00, 0x00FF00, 0x000033, 0x000066,

522 0x000099, 0x0000CC, 0x0000FF, 0x333300, 0x666600, 0x999900,

523 0xCCCC00, 0xFFFF00, 0x003333, 0x006666, 0x009999, 0x00CCCC,

524 0x00FFFF, 0x330033, 0x660066, 0x990099, 0xCC00CC, 0xFF00FF,

525 0xFFFF33, 0xFFFF66, 0xFFFF99, 0xFFFFCC, 0xFF33FF, 0xFF66FF,

526 0xFF99FF, 0xFFCCFF, 0x33FFFF, 0x66FFFF, 0x99FFFF, 0xCCFFFF,

527 0xCCCC33, 0xCCCC66, 0xCCCC99, 0xCCCCFF, 0xCC33CC, 0xCC66CC,

528 0xCC99CC, 0xCCFFCC, 0x33CCCC, 0x66CCCC, 0x99CCCC, 0xFFCCCC,

529 0x999933, 0x999966, 0x9999CC, 0x9999FF, 0x993399, 0x996699,

530 0x99CC99, 0x99FF99, 0x339999, 0x669999, 0xCC9999, 0xFF9999,

531 0x666633, 0x666699, 0x6666CC, 0x6666FF, 0x663366, 0x669966,

532 0x66CC66, 0x66FF66, 0x336666, 0x996666, 0xCC6666, 0xFF6666,

533 0x333366, 0x333399, 0x3333CC, 0x3333FF, 0x336633, 0x339933,

534 0x33CC33, 0x33FF33, 0x663333, 0x993333, 0xCC3333, 0xFF3333,

535 0x003366, 0x336600, 0x660033, 0x006633, 0x330066, 0x663300,

536 0x336699, 0x669933, 0x993366, 0x339966, 0x663399, 0x996633,

537 0x6699CC, 0x99CC66, 0xCC6699, 0x66CC99, 0x9966CC, 0xCC9966,

538 0x99CCFF, 0xCCFF99, 0xFF99CC, 0x99FFCC, 0xCC99FF, 0xFFCC99,

539 0x111111, 0x222222, 0x444444, 0x555555, 0xAAAAAA, 0xBBBBBB,

540 0xDDDDDD, 0xEEEEEE

541 };

542

543 static av_cold int flashsv2_decode_init(AVCodecContext *avctx)

544 {

545 FlashSVContext *s = avctx->priv_data;

546 flashsv_decode_init(avctx);

547 s->pal = ff_flashsv2_default_palette;

548 s->ver = 2;

549

550 return 0;

551 }

552

553 static av_cold int flashsv2_decode_end(AVCodecContext *avctx)

554 {

555 FlashSVContext *s = avctx->priv_data;

556

557 av_freep(&s->keyframedata);

558 av_freep(&s->blocks);

559 av_freep(&s->keyframe);

560 av_freep(&s->deflate_block);

561 flashsv_decode_end(avctx);

562

563 return 0;

564 }

565

566 AVCodec ff_flashsv2_decoder = {

567 .name = "flashsv2",

568 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v2"),

569 .type = AVMEDIA_TYPE_VIDEO,

570 .id = AV_CODEC_ID_FLASHSV2,

571 .priv_data_size = sizeof(FlashSVContext),

572 .init = flashsv2_decode_init,

573 .close = flashsv2_decode_end,

574 .decode = flashsv_decode_frame,

575 .capabilities = CODEC_CAP_DR1,

576 .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },

577 };

578 #endif /* CONFIG_FLASHSV2_DECODER */

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