DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Header

Mercurial (31ec81b5d7bb)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "ImageLogging.h"
#include "nsJPEGDecoder.h"
#include "Orientation.h"
#include "EXIF.h"

#include "nsIInputStream.h"

#include "nspr.h"
#include "nsCRT.h"
#include "gfxColor.h"

#include "jerror.h"

#include "gfxPlatform.h"

extern "C" {
#include "iccjpeg.h"
}

#if defined(IS_BIG_ENDIAN)
#define MOZ_JCS_EXT_NATIVE_ENDIAN_XRGB JCS_EXT_XRGB
#else
#define MOZ_JCS_EXT_NATIVE_ENDIAN_XRGB JCS_EXT_BGRX
#endif

static void cmyk_convert_rgb(JSAMPROW row, JDIMENSION width);

namespace mozilla {
namespace image {

#if defined(PR_LOGGING)
static PRLogModuleInfo *
GetJPEGLog()
{
  static PRLogModuleInfo *sJPEGLog;
  if (!sJPEGLog)
    sJPEGLog = PR_NewLogModule("JPEGDecoder");
  return sJPEGLog;
}

static PRLogModuleInfo *
GetJPEGDecoderAccountingLog()
{
  static PRLogModuleInfo *sJPEGDecoderAccountingLog;
  if (!sJPEGDecoderAccountingLog)
    sJPEGDecoderAccountingLog = PR_NewLogModule("JPEGDecoderAccounting");
  return sJPEGDecoderAccountingLog;
}
#else
#define GetJPEGLog()
#define GetJPEGDecoderAccountingLog()
#endif

static qcms_profile*
GetICCProfile(struct jpeg_decompress_struct &info)
{
  JOCTET* profilebuf;
  uint32_t profileLength;
  qcms_profile* profile = nullptr;

  if (read_icc_profile(&info, &profilebuf, &profileLength)) {
    profile = qcms_profile_from_memory(profilebuf, profileLength);
    free(profilebuf);
  }

  return profile;
}

METHODDEF(void) init_source (j_decompress_ptr jd);
METHODDEF(boolean) fill_input_buffer (j_decompress_ptr jd);
METHODDEF(void) skip_input_data (j_decompress_ptr jd, long num_bytes);
METHODDEF(void) term_source (j_decompress_ptr jd);
METHODDEF(void) my_error_exit (j_common_ptr cinfo);

/* Normal JFIF markers can't have more bytes than this. */
#define MAX_JPEG_MARKER_LENGTH  (((uint32_t)1 << 16) - 1)


nsJPEGDecoder::nsJPEGDecoder(RasterImage& aImage, Decoder::DecodeStyle aDecodeStyle)
 : Decoder(aImage)
 , mDecodeStyle(aDecodeStyle)
{
  mState = JPEG_HEADER;
  mReading = true;
  mImageData = nullptr;

  mBytesToSkip = 0;
  memset(&mInfo, 0, sizeof(jpeg_decompress_struct));
  memset(&mSourceMgr, 0, sizeof(mSourceMgr));
  mInfo.client_data = (void*)this;

  mSegment = nullptr;
  mSegmentLen = 0;

  mBackBuffer = nullptr;
  mBackBufferLen = mBackBufferSize = mBackBufferUnreadLen = 0;

  mInProfile = nullptr;
  mTransform = nullptr;

  mCMSMode = 0;

  PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
         ("nsJPEGDecoder::nsJPEGDecoder: Creating JPEG decoder %p",
          this));
}

nsJPEGDecoder::~nsJPEGDecoder()
{
  // Step 8: Release JPEG decompression object
  mInfo.src = nullptr;
  jpeg_destroy_decompress(&mInfo);

  PR_FREEIF(mBackBuffer);
  if (mTransform)
    qcms_transform_release(mTransform);
  if (mInProfile)
    qcms_profile_release(mInProfile);

  PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
         ("nsJPEGDecoder::~nsJPEGDecoder: Destroying JPEG decoder %p",
          this));
}

Telemetry::ID
nsJPEGDecoder::SpeedHistogram()
{
  return Telemetry::IMAGE_DECODE_SPEED_JPEG;
}

void
nsJPEGDecoder::InitInternal()
{
  mCMSMode = gfxPlatform::GetCMSMode();
  if ((mDecodeFlags & DECODER_NO_COLORSPACE_CONVERSION) != 0)
    mCMSMode = eCMSMode_Off;

  /* We set up the normal JPEG error routines, then override error_exit. */
  mInfo.err = jpeg_std_error(&mErr.pub);
  /*   mInfo.err = jpeg_std_error(&mErr.pub); */
  mErr.pub.error_exit = my_error_exit;
  /* Establish the setjmp return context for my_error_exit to use. */
  if (setjmp(mErr.setjmp_buffer)) {
    /* If we get here, the JPEG code has signaled an error.
     * We need to clean up the JPEG object, close the input file, and return.
     */
    PostDecoderError(NS_ERROR_FAILURE);
    return;
  }

  /* Step 1: allocate and initialize JPEG decompression object */
  jpeg_create_decompress(&mInfo);
  /* Set the source manager */
  mInfo.src = &mSourceMgr;

  /* Step 2: specify data source (eg, a file) */

  /* Setup callback functions. */
  mSourceMgr.init_source = init_source;
  mSourceMgr.fill_input_buffer = fill_input_buffer;
  mSourceMgr.skip_input_data = skip_input_data;
  mSourceMgr.resync_to_restart = jpeg_resync_to_restart;
  mSourceMgr.term_source = term_source;

  /* Record app markers for ICC data */
  for (uint32_t m = 0; m < 16; m++)
    jpeg_save_markers(&mInfo, JPEG_APP0 + m, 0xFFFF);
}

void
nsJPEGDecoder::FinishInternal()
{
  /* If we're not in any sort of error case, flush the decoder.
   *
   * XXXbholley - It seems wrong that this should be necessary, but at the
   * moment I'm just folding the contents of Flush() into Close() so that
   * we can get rid of it.
   *
   * XXX(seth): It'd be great to get rid of this. For now, we treat this as a
   * write to a synchronous decoder, which means that this must be called only
   * on the main thread. (That's asserted in Decoder::Finish and
   * Decoder::FinishSharedDecoder.)
   */
  if ((mState != JPEG_DONE && mState != JPEG_SINK_NON_JPEG_TRAILER) &&
      (mState != JPEG_ERROR) &&
      !IsSizeDecode())
    this->Write(nullptr, 0, DECODE_SYNC);
}

void
nsJPEGDecoder::WriteInternal(const char *aBuffer, uint32_t aCount, DecodeStrategy)
{
  mSegment = (const JOCTET *)aBuffer;
  mSegmentLen = aCount;

  NS_ABORT_IF_FALSE(!HasError(), "Shouldn't call WriteInternal after error!");

  /* Return here if there is a fatal error within libjpeg. */
  nsresult error_code;
  // This cast to nsresult makes sense because setjmp() returns whatever we
  // passed to longjmp(), which was actually an nsresult.
  if ((error_code = (nsresult)setjmp(mErr.setjmp_buffer)) != NS_OK) {
    if (error_code == NS_ERROR_FAILURE) {
      PostDataError();
      /* Error due to corrupt stream - return NS_OK and consume silently
         so that libpr0n doesn't throw away a partial image load */
      mState = JPEG_SINK_NON_JPEG_TRAILER;
      PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
             ("} (setjmp returned NS_ERROR_FAILURE)"));
      return;
    } else {
      /* Error due to reasons external to the stream (probably out of
         memory) - let libpr0n attempt to clean up, even though
         mozilla is seconds away from falling flat on its face. */
      PostDecoderError(error_code);
      mState = JPEG_ERROR;
      PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
             ("} (setjmp returned an error)"));
      return;
    }
  }

  PR_LOG(GetJPEGLog(), PR_LOG_DEBUG,
         ("[this=%p] nsJPEGDecoder::Write -- processing JPEG data\n", this));

  switch (mState) {
  case JPEG_HEADER:
  {
    LOG_SCOPE(GetJPEGLog(), "nsJPEGDecoder::Write -- entering JPEG_HEADER case");

    /* Step 3: read file parameters with jpeg_read_header() */
    if (jpeg_read_header(&mInfo, TRUE) == JPEG_SUSPENDED) {
      PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
             ("} (JPEG_SUSPENDED)"));
      return; /* I/O suspension */
    }

    // Post our size to the superclass
    PostSize(mInfo.image_width, mInfo.image_height, ReadOrientationFromEXIF());
    if (HasError()) {
      // Setting the size led to an error.
      mState = JPEG_ERROR;
      return;
    }

    /* If we're doing a size decode, we're done. */
    if (IsSizeDecode())
      return;

    /* We're doing a full decode. */
    if (mCMSMode != eCMSMode_Off &&
        (mInProfile = GetICCProfile(mInfo)) != nullptr) {
      uint32_t profileSpace = qcms_profile_get_color_space(mInProfile);
      bool mismatch = false;

#ifdef DEBUG_tor
      fprintf(stderr, "JPEG profileSpace: 0x%08X\n", profileSpace);
#endif
      switch (mInfo.jpeg_color_space) {
      case JCS_GRAYSCALE:
        if (profileSpace == icSigRgbData)
          mInfo.out_color_space = JCS_RGB;
        else if (profileSpace != icSigGrayData)
          mismatch = true;
        break;
      case JCS_RGB:
        if (profileSpace != icSigRgbData)
          mismatch =  true;
        break;
      case JCS_YCbCr:
        if (profileSpace == icSigRgbData)
          mInfo.out_color_space = JCS_RGB;
        else
	  // qcms doesn't support ycbcr
          mismatch = true;
        break;
      case JCS_CMYK:
      case JCS_YCCK:
	  // qcms doesn't support cmyk
          mismatch = true;
        break;
      default:
        mState = JPEG_ERROR;
        PostDataError();
        PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
               ("} (unknown colorpsace (1))"));
        return;
      }

      if (!mismatch) {
        qcms_data_type type;
        switch (mInfo.out_color_space) {
        case JCS_GRAYSCALE:
          type = QCMS_DATA_GRAY_8;
          break;
        case JCS_RGB:
          type = QCMS_DATA_RGB_8;
          break;
        default:
          mState = JPEG_ERROR;
          PostDataError();
          PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
                 ("} (unknown colorpsace (2))"));
          return;
        }
#if 0
        /* We don't currently support CMYK profiles. The following
         * code dealt with lcms types. Add something like this
         * back when we gain support for CMYK.
         */
        /* Adobe Photoshop writes YCCK/CMYK files with inverted data */
        if (mInfo.out_color_space == JCS_CMYK)
          type |= FLAVOR_SH(mInfo.saw_Adobe_marker ? 1 : 0);
#endif

        if (gfxPlatform::GetCMSOutputProfile()) {

          /* Calculate rendering intent. */
          int intent = gfxPlatform::GetRenderingIntent();
          if (intent == -1)
              intent = qcms_profile_get_rendering_intent(mInProfile);

          /* Create the color management transform. */
          mTransform = qcms_transform_create(mInProfile,
                                          type,
                                          gfxPlatform::GetCMSOutputProfile(),
                                          QCMS_DATA_RGB_8,
                                          (qcms_intent)intent);
        }
      } else {
#ifdef DEBUG_tor
        fprintf(stderr, "ICM profile colorspace mismatch\n");
#endif
      }
    }

    if (!mTransform) {
      switch (mInfo.jpeg_color_space) {
      case JCS_GRAYSCALE:
      case JCS_RGB:
      case JCS_YCbCr:
        // if we're not color managing we can decode directly to
        // MOZ_JCS_EXT_NATIVE_ENDIAN_XRGB
        if (mCMSMode != eCMSMode_All) {
            mInfo.out_color_space = MOZ_JCS_EXT_NATIVE_ENDIAN_XRGB;
            mInfo.out_color_components = 4;
        } else {
            mInfo.out_color_space = JCS_RGB;
        }
        break;
      case JCS_CMYK:
      case JCS_YCCK:
        /* libjpeg can convert from YCCK to CMYK, but not to RGB */
        mInfo.out_color_space = JCS_CMYK;
        break;
      default:
        mState = JPEG_ERROR;
        PostDataError();
        PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
               ("} (unknown colorpsace (3))"));
        return;
        break;
      }
    }

    /*
     * Don't allocate a giant and superfluous memory buffer
     * when not doing a progressive decode.
     */
    mInfo.buffered_image = mDecodeStyle == PROGRESSIVE && jpeg_has_multiple_scans(&mInfo);

    /* Used to set up image size so arrays can be allocated */
    jpeg_calc_output_dimensions(&mInfo);

    if (!mImageData) {
      mState = JPEG_ERROR;
      PostDecoderError(NS_ERROR_OUT_OF_MEMORY);
      PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
             ("} (could not initialize image frame)"));
      return;
    }

    PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
           ("        JPEGDecoderAccounting: nsJPEGDecoder::Write -- created image frame with %ux%u pixels",
            mInfo.image_width, mInfo.image_height));

    mState = JPEG_START_DECOMPRESS;
  }

  case JPEG_START_DECOMPRESS:
  {
    LOG_SCOPE(GetJPEGLog(), "nsJPEGDecoder::Write -- entering JPEG_START_DECOMPRESS case");
    /* Step 4: set parameters for decompression */

    /* FIXME -- Should reset dct_method and dither mode
     * for final pass of progressive JPEG
     */
    mInfo.dct_method =  JDCT_ISLOW;
    mInfo.dither_mode = JDITHER_FS;
    mInfo.do_fancy_upsampling = TRUE;
    mInfo.enable_2pass_quant = FALSE;
    mInfo.do_block_smoothing = TRUE;

    /* Step 5: Start decompressor */
    if (jpeg_start_decompress(&mInfo) == FALSE) {
      PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
             ("} (I/O suspension after jpeg_start_decompress())"));
      return; /* I/O suspension */
    }


    /* If this is a progressive JPEG ... */
    mState = mInfo.buffered_image ? JPEG_DECOMPRESS_PROGRESSIVE : JPEG_DECOMPRESS_SEQUENTIAL;
  }

  case JPEG_DECOMPRESS_SEQUENTIAL:
  {
    if (mState == JPEG_DECOMPRESS_SEQUENTIAL)
    {
      LOG_SCOPE(GetJPEGLog(), "nsJPEGDecoder::Write -- JPEG_DECOMPRESS_SEQUENTIAL case");
      
      bool suspend;
      OutputScanlines(&suspend);
      
      if (suspend) {
        PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
               ("} (I/O suspension after OutputScanlines() - SEQUENTIAL)"));
        return; /* I/O suspension */
      }
      
      /* If we've completed image output ... */
      NS_ASSERTION(mInfo.output_scanline == mInfo.output_height, "We didn't process all of the data!");
      mState = JPEG_DONE;
    }
  }

  case JPEG_DECOMPRESS_PROGRESSIVE:
  {
    if (mState == JPEG_DECOMPRESS_PROGRESSIVE)
    {
      LOG_SCOPE(GetJPEGLog(), "nsJPEGDecoder::Write -- JPEG_DECOMPRESS_PROGRESSIVE case");

      int status;
      do {
        status = jpeg_consume_input(&mInfo);
      } while ((status != JPEG_SUSPENDED) &&
               (status != JPEG_REACHED_EOI));

      for (;;) {
        if (mInfo.output_scanline == 0) {
          int scan = mInfo.input_scan_number;

          /* if we haven't displayed anything yet (output_scan_number==0)
             and we have enough data for a complete scan, force output
             of the last full scan */
          if ((mInfo.output_scan_number == 0) &&
              (scan > 1) &&
              (status != JPEG_REACHED_EOI))
            scan--;

          if (!jpeg_start_output(&mInfo, scan)) {
            PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
                   ("} (I/O suspension after jpeg_start_output() - PROGRESSIVE)"));
            return; /* I/O suspension */
          }
        }

        if (mInfo.output_scanline == 0xffffff)
          mInfo.output_scanline = 0;

        bool suspend;
        OutputScanlines(&suspend);

        if (suspend) {
          if (mInfo.output_scanline == 0) {
            /* didn't manage to read any lines - flag so we don't call
               jpeg_start_output() multiple times for the same scan */
            mInfo.output_scanline = 0xffffff;
          }
          PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
                 ("} (I/O suspension after OutputScanlines() - PROGRESSIVE)"));
          return; /* I/O suspension */
        }

        if (mInfo.output_scanline == mInfo.output_height)
        {
          if (!jpeg_finish_output(&mInfo)) {
            PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
                   ("} (I/O suspension after jpeg_finish_output() - PROGRESSIVE)"));
            return; /* I/O suspension */
          }

          if (jpeg_input_complete(&mInfo) &&
              (mInfo.input_scan_number == mInfo.output_scan_number))
            break;

          mInfo.output_scanline = 0;
        }
      }

      mState = JPEG_DONE;
    }
  }

  case JPEG_DONE:
  {
    LOG_SCOPE(GetJPEGLog(), "nsJPEGDecoder::ProcessData -- entering JPEG_DONE case");

    /* Step 7: Finish decompression */

    if (jpeg_finish_decompress(&mInfo) == FALSE) {
      PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
             ("} (I/O suspension after jpeg_finish_decompress() - DONE)"));
      return; /* I/O suspension */
    }

    mState = JPEG_SINK_NON_JPEG_TRAILER;

    /* we're done dude */
    break;
  }
  case JPEG_SINK_NON_JPEG_TRAILER:
    PR_LOG(GetJPEGLog(), PR_LOG_DEBUG,
           ("[this=%p] nsJPEGDecoder::ProcessData -- entering JPEG_SINK_NON_JPEG_TRAILER case\n", this));

    break;

  case JPEG_ERROR:
    NS_ABORT_IF_FALSE(0, "Should always return immediately after error and not re-enter decoder");
  }

  PR_LOG(GetJPEGDecoderAccountingLog(), PR_LOG_DEBUG,
         ("} (end of function)"));
  return;
}

Orientation
nsJPEGDecoder::ReadOrientationFromEXIF()
{
  jpeg_saved_marker_ptr marker;

  // Locate the APP1 marker, where EXIF data is stored, in the marker list.
  for (marker = mInfo.marker_list ; marker != nullptr ; marker = marker->next) {
    if (marker->marker == JPEG_APP0 + 1) 
      break;
  }

  // If we're at the end of the list, there's no EXIF data.
  if (!marker)
    return Orientation();

  // Extract the orientation information.
  EXIFData exif = EXIFParser::Parse(marker->data,
                                    static_cast<uint32_t>(marker->data_length));
  return exif.orientation;
}

void
nsJPEGDecoder::NotifyDone()
{
  PostFrameStop(FrameBlender::kFrameOpaque);
  PostDecodeDone();
}

void
nsJPEGDecoder::OutputScanlines(bool* suspend)
{
  *suspend = false;

  const uint32_t top = mInfo.output_scanline;

  while ((mInfo.output_scanline < mInfo.output_height)) {
      /* Use the Cairo image buffer as scanline buffer */
      uint32_t *imageRow = ((uint32_t*)mImageData) +
                           (mInfo.output_scanline * mInfo.output_width);

      if (mInfo.out_color_space == MOZ_JCS_EXT_NATIVE_ENDIAN_XRGB) {
        /* Special case: scanline will be directly converted into packed ARGB */
        if (jpeg_read_scanlines(&mInfo, (JSAMPARRAY)&imageRow, 1) != 1) {
          *suspend = true; /* suspend */
          break;
        }
        continue; /* all done for this row! */
      }

      JSAMPROW sampleRow = (JSAMPROW)imageRow;
      if (mInfo.output_components == 3) {
        /* Put the pixels at end of row to enable in-place expansion */
        sampleRow += mInfo.output_width;
      }

      /* Request one scanline.  Returns 0 or 1 scanlines. */    
      if (jpeg_read_scanlines(&mInfo, &sampleRow, 1) != 1) {
        *suspend = true; /* suspend */
        break;
      }

      if (mTransform) {
        JSAMPROW source = sampleRow;
        if (mInfo.out_color_space == JCS_GRAYSCALE) {
          /* Convert from the 1byte grey pixels at begin of row 
             to the 3byte RGB byte pixels at 'end' of row */
          sampleRow += mInfo.output_width;
        }
        qcms_transform_data(mTransform, source, sampleRow, mInfo.output_width);
        /* Move 3byte RGB data to end of row */
        if (mInfo.out_color_space == JCS_CMYK) {
          memmove(sampleRow + mInfo.output_width,
                  sampleRow,
                  3 * mInfo.output_width);
          sampleRow += mInfo.output_width;
        }
      } else {
        if (mInfo.out_color_space == JCS_CMYK) {
          /* Convert from CMYK to RGB */
          /* We cannot convert directly to Cairo, as the CMSRGBTransform may wants to do a RGB transform... */
          /* Would be better to have platform CMSenabled transformation from CMYK to (A)RGB... */
          cmyk_convert_rgb((JSAMPROW)imageRow, mInfo.output_width);
          sampleRow += mInfo.output_width;
        }
        if (mCMSMode == eCMSMode_All) {
          /* No embedded ICC profile - treat as sRGB */
          qcms_transform *transform = gfxPlatform::GetCMSRGBTransform();
          if (transform) {
            qcms_transform_data(transform, sampleRow, sampleRow, mInfo.output_width);
          }
        }
      }

      // counter for while() loops below
      uint32_t idx = mInfo.output_width;

      // copy as bytes until source pointer is 32-bit-aligned
      for (; (NS_PTR_TO_UINT32(sampleRow) & 0x3) && idx; --idx) {
        *imageRow++ = gfxPackedPixel(0xFF, sampleRow[0], sampleRow[1], sampleRow[2]);
        sampleRow += 3;
      }

      // copy pixels in blocks of 4
      while (idx >= 4) {
        GFX_BLOCK_RGB_TO_FRGB(sampleRow, imageRow);
        idx       -=  4;
        sampleRow += 12;
        imageRow  +=  4;
      }

      // copy remaining pixel(s)
      while (idx--) {
        // 32-bit read of final pixel will exceed buffer, so read bytes
        *imageRow++ = gfxPackedPixel(0xFF, sampleRow[0], sampleRow[1], sampleRow[2]);
        sampleRow += 3;
      }
  }

  if (top != mInfo.output_scanline) {
      nsIntRect r(0, top, mInfo.output_width, mInfo.output_scanline-top);
      PostInvalidation(r);
  }

}


/* Override the standard error method in the IJG JPEG decoder code. */
METHODDEF(void)
my_error_exit (j_common_ptr cinfo)
{
  decoder_error_mgr *err = (decoder_error_mgr *) cinfo->err;

  /* Convert error to a browser error code */
  nsresult error_code = err->pub.msg_code == JERR_OUT_OF_MEMORY
                      ? NS_ERROR_OUT_OF_MEMORY
                      : NS_ERROR_FAILURE;

#ifdef DEBUG
  char buffer[JMSG_LENGTH_MAX];

  /* Create the message */
  (*err->pub.format_message) (cinfo, buffer);

  fprintf(stderr, "JPEG decoding error:\n%s\n", buffer);
#endif

  /* Return control to the setjmp point.  We pass an nsresult masquerading as
   * an int, which works because the setjmp() caller casts it back. */
  longjmp(err->setjmp_buffer, static_cast<int>(error_code));
}

/******************************************************************************/
/*-----------------------------------------------------------------------------
 * This is the callback routine from the IJG JPEG library used to supply new
 * data to the decompressor when its input buffer is exhausted.  It juggles
 * multiple buffers in an attempt to avoid unnecessary copying of input data.
 *
 * (A simpler scheme is possible: It's much easier to use only a single
 * buffer; when fill_input_buffer() is called, move any unconsumed data
 * (beyond the current pointer/count) down to the beginning of this buffer and
 * then load new data into the remaining buffer space.  This approach requires
 * a little more data copying but is far easier to get right.)
 *
 * At any one time, the JPEG decompressor is either reading from the necko
 * input buffer, which is volatile across top-level calls to the IJG library,
 * or the "backtrack" buffer.  The backtrack buffer contains the remaining
 * unconsumed data from the necko buffer after parsing was suspended due
 * to insufficient data in some previous call to the IJG library.
 *
 * When suspending, the decompressor will back up to a convenient restart
 * point (typically the start of the current MCU). The variables
 * next_input_byte & bytes_in_buffer indicate where the restart point will be
 * if the current call returns FALSE.  Data beyond this point must be
 * rescanned after resumption, so it must be preserved in case the decompressor
 * decides to backtrack.
 *
 * Returns:
 *  TRUE if additional data is available, FALSE if no data present and
 *   the JPEG library should therefore suspend processing of input stream
 *---------------------------------------------------------------------------*/

/******************************************************************************/
/* data source manager method                                                 */
/******************************************************************************/


/******************************************************************************/
/* data source manager method 
        Initialize source.  This is called by jpeg_read_header() before any
        data is actually read.  May leave
        bytes_in_buffer set to 0 (in which case a fill_input_buffer() call
        will occur immediately).
*/
METHODDEF(void)
init_source (j_decompress_ptr jd)
{
}

/******************************************************************************/
/* data source manager method
        Skip num_bytes worth of data.  The buffer pointer and count should
        be advanced over num_bytes input bytes, refilling the buffer as
        needed.  This is used to skip over a potentially large amount of
        uninteresting data (such as an APPn marker).  In some applications
        it may be possible to optimize away the reading of the skipped data,
        but it's not clear that being smart is worth much trouble; large
        skips are uncommon.  bytes_in_buffer may be zero on return.
        A zero or negative skip count should be treated as a no-op.
*/
METHODDEF(void)
skip_input_data (j_decompress_ptr jd, long num_bytes)
{
  struct jpeg_source_mgr *src = jd->src;
  nsJPEGDecoder *decoder = (nsJPEGDecoder *)(jd->client_data);

  if (num_bytes > (long)src->bytes_in_buffer) {
    /*
     * Can't skip it all right now until we get more data from
     * network stream. Set things up so that fill_input_buffer
     * will skip remaining amount.
     */
    decoder->mBytesToSkip = (size_t)num_bytes - src->bytes_in_buffer;
    src->next_input_byte += src->bytes_in_buffer;
    src->bytes_in_buffer = 0;

  } else {
    /* Simple case. Just advance buffer pointer */

    src->bytes_in_buffer -= (size_t)num_bytes;
    src->next_input_byte += num_bytes;
  }
}


/******************************************************************************/
/* data source manager method
        This is called whenever bytes_in_buffer has reached zero and more
        data is wanted.  In typical applications, it should read fresh data
        into the buffer (ignoring the current state of next_input_byte and
        bytes_in_buffer), reset the pointer & count to the start of the
        buffer, and return TRUE indicating that the buffer has been reloaded.
        It is not necessary to fill the buffer entirely, only to obtain at
        least one more byte.  bytes_in_buffer MUST be set to a positive value
        if TRUE is returned.  A FALSE return should only be used when I/O
        suspension is desired.
*/
METHODDEF(boolean)
fill_input_buffer (j_decompress_ptr jd)
{
  struct jpeg_source_mgr *src = jd->src;
  nsJPEGDecoder *decoder = (nsJPEGDecoder *)(jd->client_data);

  if (decoder->mReading) {
    const JOCTET *new_buffer = decoder->mSegment;
    uint32_t new_buflen = decoder->mSegmentLen;
  
    if (!new_buffer || new_buflen == 0)
      return false; /* suspend */

    decoder->mSegmentLen = 0;

    if (decoder->mBytesToSkip) {
      if (decoder->mBytesToSkip < new_buflen) {
        /* All done skipping bytes; Return what's left. */
        new_buffer += decoder->mBytesToSkip;
        new_buflen -= decoder->mBytesToSkip;
        decoder->mBytesToSkip = 0;
      } else {
        /* Still need to skip some more data in the future */
        decoder->mBytesToSkip -= (size_t)new_buflen;
        return false; /* suspend */
      }
    }

      decoder->mBackBufferUnreadLen = src->bytes_in_buffer;

    src->next_input_byte = new_buffer;
    src->bytes_in_buffer = (size_t)new_buflen;
    decoder->mReading = false;

    return true;
  }

  if (src->next_input_byte != decoder->mSegment) {
    /* Backtrack data has been permanently consumed. */
    decoder->mBackBufferUnreadLen = 0;
    decoder->mBackBufferLen = 0;
  }

  /* Save remainder of netlib buffer in backtrack buffer */
  const uint32_t new_backtrack_buflen = src->bytes_in_buffer + decoder->mBackBufferLen;
 
  /* Make sure backtrack buffer is big enough to hold new data. */
  if (decoder->mBackBufferSize < new_backtrack_buflen) {
    /* Check for malformed MARKER segment lengths, before allocating space for it */
    if (new_backtrack_buflen > MAX_JPEG_MARKER_LENGTH) {
      my_error_exit((j_common_ptr)(&decoder->mInfo));
    }

    /* Round up to multiple of 256 bytes. */
    const size_t roundup_buflen = ((new_backtrack_buflen + 255) >> 8) << 8;
    JOCTET *buf = (JOCTET *)PR_REALLOC(decoder->mBackBuffer, roundup_buflen);
    /* Check for OOM */
    if (!buf) {
      decoder->mInfo.err->msg_code = JERR_OUT_OF_MEMORY;
      my_error_exit((j_common_ptr)(&decoder->mInfo));
    }
    decoder->mBackBuffer = buf;
    decoder->mBackBufferSize = roundup_buflen;
  }

  /* Copy remainder of netlib segment into backtrack buffer. */
  memmove(decoder->mBackBuffer + decoder->mBackBufferLen,
          src->next_input_byte,
          src->bytes_in_buffer);

  /* Point to start of data to be rescanned. */
  src->next_input_byte = decoder->mBackBuffer + decoder->mBackBufferLen - decoder->mBackBufferUnreadLen;
  src->bytes_in_buffer += decoder->mBackBufferUnreadLen;
  decoder->mBackBufferLen = (size_t)new_backtrack_buflen;
  decoder->mReading = true;

  return false;
}

/******************************************************************************/
/* data source manager method */
/*
 * Terminate source --- called by jpeg_finish_decompress() after all
 * data has been read to clean up JPEG source manager. NOT called by 
 * jpeg_abort() or jpeg_destroy().
 */
METHODDEF(void)
term_source (j_decompress_ptr jd)
{
  nsJPEGDecoder *decoder = (nsJPEGDecoder *)(jd->client_data);

  // This function shouldn't be called if we ran into an error we didn't
  // recover from.
  NS_ABORT_IF_FALSE(decoder->mState != JPEG_ERROR,
                    "Calling term_source on a JPEG with mState == JPEG_ERROR!");

  // Notify using a helper method to get around protectedness issues.
  decoder->NotifyDone();
}

} // namespace image
} // namespace mozilla


/**************** Inverted CMYK -> RGB conversion **************/
/*
 * Input is (Inverted) CMYK stored as 4 bytes per pixel.
 * Output is RGB stored as 3 bytes per pixel.
 * @param row Points to row buffer containing the CMYK bytes for each pixel in the row.
 * @param width Number of pixels in the row.
 */
static void cmyk_convert_rgb(JSAMPROW row, JDIMENSION width)
{
  /* Work from end to front to shrink from 4 bytes per pixel to 3 */
  JSAMPROW in = row + width*4;
  JSAMPROW out = in;

  for (uint32_t i = width; i > 0; i--) {
    in -= 4;
    out -= 3;

    // Source is 'Inverted CMYK', output is RGB.
    // See: http://www.easyrgb.com/math.php?MATH=M12#text12
    // Or:  http://www.ilkeratalay.com/colorspacesfaq.php#rgb

    // From CMYK to CMY
    // C = ( C * ( 1 - K ) + K )
    // M = ( M * ( 1 - K ) + K )
    // Y = ( Y * ( 1 - K ) + K )

    // From Inverted CMYK to CMY is thus:
    // C = ( (1-iC) * (1 - (1-iK)) + (1-iK) ) => 1 - iC*iK
    // Same for M and Y

    // Convert from CMY (0..1) to RGB (0..1)
    // R = 1 - C => 1 - (1 - iC*iK) => iC*iK
    // G = 1 - M => 1 - (1 - iM*iK) => iM*iK
    // B = 1 - Y => 1 - (1 - iY*iK) => iY*iK
  
    // Convert from Inverted CMYK (0..255) to RGB (0..255)
    const uint32_t iC = in[0];
    const uint32_t iM = in[1];
    const uint32_t iY = in[2];
    const uint32_t iK = in[3];
    out[0] = iC*iK/255;   // Red
    out[1] = iM*iK/255;   // Green
    out[2] = iY*iK/255;   // Blue
  }
}