1 /* 2 * jcmarker.c 3 * 4 * Copyright (C) 1991-1998, Thomas G. Lane. 5 * Modified 2003-2012 by Guido Vollbeding. 6 * This file is part of the Independent JPEG Group's software. 7 * For conditions of distribution and use, see the accompanying README file. 8 * 9 * This file contains routines to write JPEG datastream markers. 10 */ 11 12 #define JPEG_INTERNALS 13 #include "jinclude.h" 14 #include "jpeglib.h" 15 16 17 typedef enum { /* JPEG marker codes */ 18 M_SOF0 = 0xc0, 19 M_SOF1 = 0xc1, 20 M_SOF2 = 0xc2, 21 M_SOF3 = 0xc3, 22 23 M_SOF5 = 0xc5, 24 M_SOF6 = 0xc6, 25 M_SOF7 = 0xc7, 26 27 M_JPG = 0xc8, 28 M_SOF9 = 0xc9, 29 M_SOF10 = 0xca, 30 M_SOF11 = 0xcb, 31 32 M_SOF13 = 0xcd, 33 M_SOF14 = 0xce, 34 M_SOF15 = 0xcf, 35 36 M_DHT = 0xc4, 37 38 M_DAC = 0xcc, 39 40 M_RST0 = 0xd0, 41 M_RST1 = 0xd1, 42 M_RST2 = 0xd2, 43 M_RST3 = 0xd3, 44 M_RST4 = 0xd4, 45 M_RST5 = 0xd5, 46 M_RST6 = 0xd6, 47 M_RST7 = 0xd7, 48 49 M_SOI = 0xd8, 50 M_EOI = 0xd9, 51 M_SOS = 0xda, 52 M_DQT = 0xdb, 53 M_DNL = 0xdc, 54 M_DRI = 0xdd, 55 M_DHP = 0xde, 56 M_EXP = 0xdf, 57 58 M_APP0 = 0xe0, 59 M_APP1 = 0xe1, 60 M_APP2 = 0xe2, 61 M_APP3 = 0xe3, 62 M_APP4 = 0xe4, 63 M_APP5 = 0xe5, 64 M_APP6 = 0xe6, 65 M_APP7 = 0xe7, 66 M_APP8 = 0xe8, 67 M_APP9 = 0xe9, 68 M_APP10 = 0xea, 69 M_APP11 = 0xeb, 70 M_APP12 = 0xec, 71 M_APP13 = 0xed, 72 M_APP14 = 0xee, 73 M_APP15 = 0xef, 74 75 M_JPG0 = 0xf0, 76 M_JPG8 = 0xf8, 77 M_JPG13 = 0xfd, 78 M_COM = 0xfe, 79 80 M_TEM = 0x01, 81 82 M_ERROR = 0x100 83 } JPEG_MARKER; 84 85 86 /* Private state */ 87 88 typedef struct { 89 struct jpeg_marker_writer pub; /* public fields */ 90 91 unsigned int last_restart_interval; /* last DRI value emitted; 0 after SOI */ 92 } my_marker_writer; 93 94 typedef my_marker_writer * my_marker_ptr; 95 96 97 /* 98 * Basic output routines. 99 * 100 * Note that we do not support suspension while writing a marker. 101 * Therefore, an application using suspension must ensure that there is 102 * enough buffer space for the initial markers (typ. 600-700 bytes) before 103 * calling jpeg_start_compress, and enough space to write the trailing EOI 104 * (a few bytes) before calling jpeg_finish_compress. Multipass compression 105 * modes are not supported at all with suspension, so those two are the only 106 * points where markers will be written. 107 */ 108 109 LOCAL(void) 110 emit_byte (j_compress_ptr cinfo, int val) 111 /* Emit a byte */ 112 { 113 struct jpeg_destination_mgr * dest = cinfo->dest; 114 115 *(dest->next_output_byte)++ = (JOCTET) val; 116 if (--dest->free_in_buffer == 0) { 117 if (! (*dest->empty_output_buffer) (cinfo)) 118 ERREXIT(cinfo, JERR_CANT_SUSPEND); 119 } 120 } 121 122 123 LOCAL(void) 124 emit_marker (j_compress_ptr cinfo, JPEG_MARKER mark) 125 /* Emit a marker code */ 126 { 127 emit_byte(cinfo, 0xFF); 128 emit_byte(cinfo, (int) mark); 129 } 130 131 132 LOCAL(void) 133 emit_2bytes (j_compress_ptr cinfo, int value) 134 /* Emit a 2-byte integer; these are always MSB first in JPEG files */ 135 { 136 emit_byte(cinfo, (value >> 8) & 0xFF); 137 emit_byte(cinfo, value & 0xFF); 138 } 139 140 141 /* 142 * Routines to write specific marker types. 143 */ 144 145 LOCAL(int) 146 emit_dqt (j_compress_ptr cinfo, int index) 147 /* Emit a DQT marker */ 148 /* Returns the precision used (0 = 8bits, 1 = 16bits) for baseline checking */ 149 { 150 JQUANT_TBL * qtbl = cinfo->quant_tbl_ptrs[index]; 151 int prec; 152 int i; 153 154 if (qtbl == NULL) 155 ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, index); 156 157 prec = 0; 158 for (i = 0; i <= cinfo->lim_Se; i++) { 159 if (qtbl->quantval[cinfo->natural_order[i]] > 255) 160 prec = 1; 161 } 162 163 if (! qtbl->sent_table) { 164 emit_marker(cinfo, M_DQT); 165 166 emit_2bytes(cinfo, 167 prec ? cinfo->lim_Se * 2 + 2 + 1 + 2 : cinfo->lim_Se + 1 + 1 + 2); 168 169 emit_byte(cinfo, index + (prec<<4)); 170 171 for (i = 0; i <= cinfo->lim_Se; i++) { 172 /* The table entries must be emitted in zigzag order. */ 173 unsigned int qval = qtbl->quantval[cinfo->natural_order[i]]; 174 if (prec) 175 emit_byte(cinfo, (int) (qval >> 8)); 176 emit_byte(cinfo, (int) (qval & 0xFF)); 177 } 178 179 qtbl->sent_table = TRUE; 180 } 181 182 return prec; 183 } 184 185 186 LOCAL(void) 187 emit_dht (j_compress_ptr cinfo, int index, boolean is_ac) 188 /* Emit a DHT marker */ 189 { 190 JHUFF_TBL * htbl; 191 int length, i; 192 193 if (is_ac) { 194 htbl = cinfo->ac_huff_tbl_ptrs[index]; 195 index += 0x10; /* output index has AC bit set */ 196 } else { 197 htbl = cinfo->dc_huff_tbl_ptrs[index]; 198 } 199 200 if (htbl == NULL) 201 ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, index); 202 203 if (! htbl->sent_table) { 204 emit_marker(cinfo, M_DHT); 205 206 length = 0; 207 for (i = 1; i <= 16; i++) 208 length += htbl->bits[i]; 209 210 emit_2bytes(cinfo, length + 2 + 1 + 16); 211 emit_byte(cinfo, index); 212 213 for (i = 1; i <= 16; i++) 214 emit_byte(cinfo, htbl->bits[i]); 215 216 for (i = 0; i < length; i++) 217 emit_byte(cinfo, htbl->huffval[i]); 218 219 htbl->sent_table = TRUE; 220 } 221 } 222 223 224 LOCAL(void) 225 emit_dac (j_compress_ptr cinfo) 226 /* Emit a DAC marker */ 227 /* Since the useful info is so small, we want to emit all the tables in */ 228 /* one DAC marker. Therefore this routine does its own scan of the table. */ 229 { 230 #ifdef C_ARITH_CODING_SUPPORTED 231 char dc_in_use[NUM_ARITH_TBLS]; 232 char ac_in_use[NUM_ARITH_TBLS]; 233 int length, i; 234 jpeg_component_info *compptr; 235 236 for (i = 0; i < NUM_ARITH_TBLS; i++) 237 dc_in_use[i] = ac_in_use[i] = 0; 238 239 for (i = 0; i < cinfo->comps_in_scan; i++) { 240 compptr = cinfo->cur_comp_info[i]; 241 /* DC needs no table for refinement scan */ 242 if (cinfo->Ss == 0 && cinfo->Ah == 0) 243 dc_in_use[compptr->dc_tbl_no] = 1; 244 /* AC needs no table when not present */ 245 if (cinfo->Se) 246 ac_in_use[compptr->ac_tbl_no] = 1; 247 } 248 249 length = 0; 250 for (i = 0; i < NUM_ARITH_TBLS; i++) 251 length += dc_in_use[i] + ac_in_use[i]; 252 253 if (length) { 254 emit_marker(cinfo, M_DAC); 255 256 emit_2bytes(cinfo, length*2 + 2); 257 258 for (i = 0; i < NUM_ARITH_TBLS; i++) { 259 if (dc_in_use[i]) { 260 emit_byte(cinfo, i); 261 emit_byte(cinfo, cinfo->arith_dc_L[i] + (cinfo->arith_dc_U[i]<<4)); 262 } 263 if (ac_in_use[i]) { 264 emit_byte(cinfo, i + 0x10); 265 emit_byte(cinfo, cinfo->arith_ac_K[i]); 266 } 267 } 268 } 269 #endif /* C_ARITH_CODING_SUPPORTED */ 270 } 271 272 273 LOCAL(void) 274 emit_dri (j_compress_ptr cinfo) 275 /* Emit a DRI marker */ 276 { 277 emit_marker(cinfo, M_DRI); 278 279 emit_2bytes(cinfo, 4); /* fixed length */ 280 281 emit_2bytes(cinfo, (int) cinfo->restart_interval); 282 } 283 284 285 LOCAL(void) 286 emit_lse_ict (j_compress_ptr cinfo) 287 /* Emit an LSE inverse color transform specification marker */ 288 { 289 /* Support only 1 transform */ 290 if (cinfo->color_transform != JCT_SUBTRACT_GREEN || 291 cinfo->num_components < 3) 292 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); 293 294 emit_marker(cinfo, M_JPG8); 295 296 emit_2bytes(cinfo, 24); /* fixed length */ 297 298 emit_byte(cinfo, 0x0D); /* ID inverse transform specification */ 299 emit_2bytes(cinfo, MAXJSAMPLE); /* MAXTRANS */ 300 emit_byte(cinfo, 3); /* Nt=3 */ 301 emit_byte(cinfo, cinfo->comp_info[1].component_id); 302 emit_byte(cinfo, cinfo->comp_info[0].component_id); 303 emit_byte(cinfo, cinfo->comp_info[2].component_id); 304 emit_byte(cinfo, 0x80); /* F1: CENTER1=1, NORM1=0 */ 305 emit_2bytes(cinfo, 0); /* A(1,1)=0 */ 306 emit_2bytes(cinfo, 0); /* A(1,2)=0 */ 307 emit_byte(cinfo, 0); /* F2: CENTER2=0, NORM2=0 */ 308 emit_2bytes(cinfo, 1); /* A(2,1)=1 */ 309 emit_2bytes(cinfo, 0); /* A(2,2)=0 */ 310 emit_byte(cinfo, 0); /* F3: CENTER3=0, NORM3=0 */ 311 emit_2bytes(cinfo, 1); /* A(3,1)=1 */ 312 emit_2bytes(cinfo, 0); /* A(3,2)=0 */ 313 } 314 315 316 LOCAL(void) 317 emit_sof (j_compress_ptr cinfo, JPEG_MARKER code) 318 /* Emit a SOF marker */ 319 { 320 int ci; 321 jpeg_component_info *compptr; 322 323 emit_marker(cinfo, code); 324 325 emit_2bytes(cinfo, 3 * cinfo->num_components + 2 + 5 + 1); /* length */ 326 327 /* Make sure image isn't bigger than SOF field can handle */ 328 if ((long) cinfo->jpeg_height > 65535L || 329 (long) cinfo->jpeg_width > 65535L) 330 ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) 65535); 331 332 emit_byte(cinfo, cinfo->data_precision); 333 emit_2bytes(cinfo, (int) cinfo->jpeg_height); 334 emit_2bytes(cinfo, (int) cinfo->jpeg_width); 335 336 emit_byte(cinfo, cinfo->num_components); 337 338 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; 339 ci++, compptr++) { 340 emit_byte(cinfo, compptr->component_id); 341 emit_byte(cinfo, (compptr->h_samp_factor << 4) + compptr->v_samp_factor); 342 emit_byte(cinfo, compptr->quant_tbl_no); 343 } 344 } 345 346 347 LOCAL(void) 348 emit_sos (j_compress_ptr cinfo) 349 /* Emit a SOS marker */ 350 { 351 int i, td, ta; 352 jpeg_component_info *compptr; 353 354 emit_marker(cinfo, M_SOS); 355 356 emit_2bytes(cinfo, 2 * cinfo->comps_in_scan + 2 + 1 + 3); /* length */ 357 358 emit_byte(cinfo, cinfo->comps_in_scan); 359 360 for (i = 0; i < cinfo->comps_in_scan; i++) { 361 compptr = cinfo->cur_comp_info[i]; 362 emit_byte(cinfo, compptr->component_id); 363 364 /* We emit 0 for unused field(s); this is recommended by the P&M text 365 * but does not seem to be specified in the standard. 366 */ 367 368 /* DC needs no table for refinement scan */ 369 td = cinfo->Ss == 0 && cinfo->Ah == 0 ? compptr->dc_tbl_no : 0; 370 /* AC needs no table when not present */ 371 ta = cinfo->Se ? compptr->ac_tbl_no : 0; 372 373 emit_byte(cinfo, (td << 4) + ta); 374 } 375 376 emit_byte(cinfo, cinfo->Ss); 377 emit_byte(cinfo, cinfo->Se); 378 emit_byte(cinfo, (cinfo->Ah << 4) + cinfo->Al); 379 } 380 381 382 LOCAL(void) 383 emit_pseudo_sos (j_compress_ptr cinfo) 384 /* Emit a pseudo SOS marker */ 385 { 386 emit_marker(cinfo, M_SOS); 387 388 emit_2bytes(cinfo, 2 + 1 + 3); /* length */ 389 390 emit_byte(cinfo, 0); /* Ns */ 391 392 emit_byte(cinfo, 0); /* Ss */ 393 emit_byte(cinfo, cinfo->block_size * cinfo->block_size - 1); /* Se */ 394 emit_byte(cinfo, 0); /* Ah/Al */ 395 } 396 397 398 LOCAL(void) 399 emit_jfif_app0 (j_compress_ptr cinfo) 400 /* Emit a JFIF-compliant APP0 marker */ 401 { 402 /* 403 * Length of APP0 block (2 bytes) 404 * Block ID (4 bytes - ASCII "JFIF") 405 * Zero byte (1 byte to terminate the ID string) 406 * Version Major, Minor (2 bytes - major first) 407 * Units (1 byte - 0x00 = none, 0x01 = inch, 0x02 = cm) 408 * Xdpu (2 bytes - dots per unit horizontal) 409 * Ydpu (2 bytes - dots per unit vertical) 410 * Thumbnail X size (1 byte) 411 * Thumbnail Y size (1 byte) 412 */ 413 414 emit_marker(cinfo, M_APP0); 415 416 emit_2bytes(cinfo, 2 + 4 + 1 + 2 + 1 + 2 + 2 + 1 + 1); /* length */ 417 418 emit_byte(cinfo, 0x4A); /* Identifier: ASCII "JFIF" */ 419 emit_byte(cinfo, 0x46); 420 emit_byte(cinfo, 0x49); 421 emit_byte(cinfo, 0x46); 422 emit_byte(cinfo, 0); 423 emit_byte(cinfo, cinfo->JFIF_major_version); /* Version fields */ 424 emit_byte(cinfo, cinfo->JFIF_minor_version); 425 emit_byte(cinfo, cinfo->density_unit); /* Pixel size information */ 426 emit_2bytes(cinfo, (int) cinfo->X_density); 427 emit_2bytes(cinfo, (int) cinfo->Y_density); 428 emit_byte(cinfo, 0); /* No thumbnail image */ 429 emit_byte(cinfo, 0); 430 } 431 432 433 LOCAL(void) 434 emit_adobe_app14 (j_compress_ptr cinfo) 435 /* Emit an Adobe APP14 marker */ 436 { 437 /* 438 * Length of APP14 block (2 bytes) 439 * Block ID (5 bytes - ASCII "Adobe") 440 * Version Number (2 bytes - currently 100) 441 * Flags0 (2 bytes - currently 0) 442 * Flags1 (2 bytes - currently 0) 443 * Color transform (1 byte) 444 * 445 * Although Adobe TN 5116 mentions Version = 101, all the Adobe files 446 * now in circulation seem to use Version = 100, so that's what we write. 447 * 448 * We write the color transform byte as 1 if the JPEG color space is 449 * YCbCr, 2 if it's YCCK, 0 otherwise. Adobe's definition has to do with 450 * whether the encoder performed a transformation, which is pretty useless. 451 */ 452 453 emit_marker(cinfo, M_APP14); 454 455 emit_2bytes(cinfo, 2 + 5 + 2 + 2 + 2 + 1); /* length */ 456 457 emit_byte(cinfo, 0x41); /* Identifier: ASCII "Adobe" */ 458 emit_byte(cinfo, 0x64); 459 emit_byte(cinfo, 0x6F); 460 emit_byte(cinfo, 0x62); 461 emit_byte(cinfo, 0x65); 462 emit_2bytes(cinfo, 100); /* Version */ 463 emit_2bytes(cinfo, 0); /* Flags0 */ 464 emit_2bytes(cinfo, 0); /* Flags1 */ 465 switch (cinfo->jpeg_color_space) { 466 case JCS_YCbCr: 467 emit_byte(cinfo, 1); /* Color transform = 1 */ 468 break; 469 case JCS_YCCK: 470 emit_byte(cinfo, 2); /* Color transform = 2 */ 471 break; 472 default: 473 emit_byte(cinfo, 0); /* Color transform = 0 */ 474 break; 475 } 476 } 477 478 479 /* 480 * These routines allow writing an arbitrary marker with parameters. 481 * The only intended use is to emit COM or APPn markers after calling 482 * write_file_header and before calling write_frame_header. 483 * Other uses are not guaranteed to produce desirable results. 484 * Counting the parameter bytes properly is the caller's responsibility. 485 */ 486 487 METHODDEF(void) 488 write_marker_header (j_compress_ptr cinfo, int marker, unsigned int datalen) 489 /* Emit an arbitrary marker header */ 490 { 491 if (datalen > (unsigned int) 65533) /* safety check */ 492 ERREXIT(cinfo, JERR_BAD_LENGTH); 493 494 emit_marker(cinfo, (JPEG_MARKER) marker); 495 496 emit_2bytes(cinfo, (int) (datalen + 2)); /* total length */ 497 } 498 499 METHODDEF(void) 500 write_marker_byte (j_compress_ptr cinfo, int val) 501 /* Emit one byte of marker parameters following write_marker_header */ 502 { 503 emit_byte(cinfo, val); 504 } 505 506 507 /* 508 * Write datastream header. 509 * This consists of an SOI and optional APPn markers. 510 * We recommend use of the JFIF marker, but not the Adobe marker, 511 * when using YCbCr or grayscale data. The JFIF marker should NOT 512 * be used for any other JPEG colorspace. The Adobe marker is helpful 513 * to distinguish RGB, CMYK, and YCCK colorspaces. 514 * Note that an application can write additional header markers after 515 * jpeg_start_compress returns. 516 */ 517 518 METHODDEF(void) 519 write_file_header (j_compress_ptr cinfo) 520 { 521 my_marker_ptr marker = (my_marker_ptr) cinfo->marker; 522 523 emit_marker(cinfo, M_SOI); /* first the SOI */ 524 525 /* SOI is defined to reset restart interval to 0 */ 526 marker->last_restart_interval = 0; 527 528 if (cinfo->write_JFIF_header) /* next an optional JFIF APP0 */ 529 emit_jfif_app0(cinfo); 530 if (cinfo->write_Adobe_marker) /* next an optional Adobe APP14 */ 531 emit_adobe_app14(cinfo); 532 } 533 534 535 /* 536 * Write frame header. 537 * This consists of DQT and SOFn markers, 538 * a conditional LSE marker and a conditional pseudo SOS marker. 539 * Note that we do not emit the SOF until we have emitted the DQT(s). 540 * This avoids compatibility problems with incorrect implementations that 541 * try to error-check the quant table numbers as soon as they see the SOF. 542 */ 543 544 METHODDEF(void) 545 write_frame_header (j_compress_ptr cinfo) 546 { 547 int ci, prec; 548 boolean is_baseline; 549 jpeg_component_info *compptr; 550 551 /* Emit DQT for each quantization table. 552 * Note that emit_dqt() suppresses any duplicate tables. 553 */ 554 prec = 0; 555 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; 556 ci++, compptr++) { 557 prec += emit_dqt(cinfo, compptr->quant_tbl_no); 558 } 559 /* now prec is nonzero iff there are any 16-bit quant tables. */ 560 561 /* Check for a non-baseline specification. 562 * Note we assume that Huffman table numbers won't be changed later. 563 */ 564 if (cinfo->arith_code || cinfo->progressive_mode || 565 cinfo->data_precision != 8 || cinfo->block_size != DCTSIZE) { 566 is_baseline = FALSE; 567 } else { 568 is_baseline = TRUE; 569 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; 570 ci++, compptr++) { 571 if (compptr->dc_tbl_no > 1 || compptr->ac_tbl_no > 1) 572 is_baseline = FALSE; 573 } 574 if (prec && is_baseline) { 575 is_baseline = FALSE; 576 /* If it's baseline except for quantizer size, warn the user */ 577 TRACEMS(cinfo, 0, JTRC_16BIT_TABLES); 578 } 579 } 580 581 /* Emit the proper SOF marker */ 582 if (cinfo->arith_code) { 583 if (cinfo->progressive_mode) 584 emit_sof(cinfo, M_SOF10); /* SOF code for progressive arithmetic */ 585 else 586 emit_sof(cinfo, M_SOF9); /* SOF code for sequential arithmetic */ 587 } else { 588 if (cinfo->progressive_mode) 589 emit_sof(cinfo, M_SOF2); /* SOF code for progressive Huffman */ 590 else if (is_baseline) 591 emit_sof(cinfo, M_SOF0); /* SOF code for baseline implementation */ 592 else 593 emit_sof(cinfo, M_SOF1); /* SOF code for non-baseline Huffman file */ 594 } 595 596 /* Check to emit LSE inverse color transform specification marker */ 597 if (cinfo->color_transform) 598 emit_lse_ict(cinfo); 599 600 /* Check to emit pseudo SOS marker */ 601 if (cinfo->progressive_mode && cinfo->block_size != DCTSIZE) 602 emit_pseudo_sos(cinfo); 603 } 604 605 606 /* 607 * Write scan header. 608 * This consists of DHT or DAC markers, optional DRI, and SOS. 609 * Compressed data will be written following the SOS. 610 */ 611 612 METHODDEF(void) 613 write_scan_header (j_compress_ptr cinfo) 614 { 615 my_marker_ptr marker = (my_marker_ptr) cinfo->marker; 616 int i; 617 jpeg_component_info *compptr; 618 619 if (cinfo->arith_code) { 620 /* Emit arith conditioning info. We may have some duplication 621 * if the file has multiple scans, but it's so small it's hardly 622 * worth worrying about. 623 */ 624 emit_dac(cinfo); 625 } else { 626 /* Emit Huffman tables. 627 * Note that emit_dht() suppresses any duplicate tables. 628 */ 629 for (i = 0; i < cinfo->comps_in_scan; i++) { 630 compptr = cinfo->cur_comp_info[i]; 631 /* DC needs no table for refinement scan */ 632 if (cinfo->Ss == 0 && cinfo->Ah == 0) 633 emit_dht(cinfo, compptr->dc_tbl_no, FALSE); 634 /* AC needs no table when not present */ 635 if (cinfo->Se) 636 emit_dht(cinfo, compptr->ac_tbl_no, TRUE); 637 } 638 } 639 640 /* Emit DRI if required --- note that DRI value could change for each scan. 641 * We avoid wasting space with unnecessary DRIs, however. 642 */ 643 if (cinfo->restart_interval != marker->last_restart_interval) { 644 emit_dri(cinfo); 645 marker->last_restart_interval = cinfo->restart_interval; 646 } 647 648 emit_sos(cinfo); 649 } 650 651 652 /* 653 * Write datastream trailer. 654 */ 655 656 METHODDEF(void) 657 write_file_trailer (j_compress_ptr cinfo) 658 { 659 emit_marker(cinfo, M_EOI); 660 } 661 662 663 /* 664 * Write an abbreviated table-specification datastream. 665 * This consists of SOI, DQT and DHT tables, and EOI. 666 * Any table that is defined and not marked sent_table = TRUE will be 667 * emitted. Note that all tables will be marked sent_table = TRUE at exit. 668 */ 669 670 METHODDEF(void) 671 write_tables_only (j_compress_ptr cinfo) 672 { 673 int i; 674 675 emit_marker(cinfo, M_SOI); 676 677 for (i = 0; i < NUM_QUANT_TBLS; i++) { 678 if (cinfo->quant_tbl_ptrs[i] != NULL) 679 (void) emit_dqt(cinfo, i); 680 } 681 682 if (! cinfo->arith_code) { 683 for (i = 0; i < NUM_HUFF_TBLS; i++) { 684 if (cinfo->dc_huff_tbl_ptrs[i] != NULL) 685 emit_dht(cinfo, i, FALSE); 686 if (cinfo->ac_huff_tbl_ptrs[i] != NULL) 687 emit_dht(cinfo, i, TRUE); 688 } 689 } 690 691 emit_marker(cinfo, M_EOI); 692 } 693 694 695 /* 696 * Initialize the marker writer module. 697 */ 698 699 GLOBAL(void) 700 jinit_marker_writer (j_compress_ptr cinfo) 701 { 702 my_marker_ptr marker; 703 704 /* Create the subobject */ 705 marker = (my_marker_ptr) 706 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, 707 SIZEOF(my_marker_writer)); 708 cinfo->marker = &marker->pub; 709 /* Initialize method pointers */ 710 marker->pub.write_file_header = write_file_header; 711 marker->pub.write_frame_header = write_frame_header; 712 marker->pub.write_scan_header = write_scan_header; 713 marker->pub.write_file_trailer = write_file_trailer; 714 marker->pub.write_tables_only = write_tables_only; 715 marker->pub.write_marker_header = write_marker_header; 716 marker->pub.write_marker_byte = write_marker_byte; 717 /* Initialize private state */ 718 marker->last_restart_interval = 0; 719 } 720
