C++ TiffIFD类代码示例

string NefDecoder::getMode() {
  ostringstream mode;
  vector<TiffIFD*>  data = mRootIFD->getIFDsWithTag(CFAPATTERN);
  TiffIFD* raw = FindBestImage(&data);
  int compression = raw->getEntry(COMPRESSION)->getInt();
  uint32 bitPerPixel = raw->getEntry(BITSPERSAMPLE)->getInt();
  if (1 == compression)
    mode << bitPerPixel << "bit-uncompressed";
  else
    mode << bitPerPixel << "bit-uncompressed";
  return mode.str();
}

TiffIFD* NefDecoder::FindBestImage(vector<TiffIFD*>* data) {
  int largest_width = 0;
  TiffIFD* best_ifd = NULL;
  for (int i = 0; i < (int)data->size(); i++) {
    TiffIFD* raw = (*data)[i];
    int width = raw->getEntry(IMAGEWIDTH)->getInt();
    if (width > largest_width)
      best_ifd = raw;
  }
  if (NULL == best_ifd)
    ThrowRDE("NEF Decoder: Unable to locate image");
  return best_ifd;
}

void KdcDecoder::decodeMetaDataInternal(CameraMetaData *meta) {
  vector<TiffIFD*> data = mRootIFD->getIFDsWithTag(MODEL);

  if (data.empty())
    ThrowRDE("KDC Decoder: Model name found");
  if (!data[0]->hasEntry(MAKE))
    ThrowRDE("KDC Decoder: Make name not found");

  string make = data[0]->getEntry(MAKE)->getString();
  string model = data[0]->getEntry(MODEL)->getString();
  setMetaData(meta, make, model, "", 0);

  // Try the kodak hidden IFD for WB
  if (mRootIFD->hasEntryRecursive(KODAK_IFD2)) {
    TiffEntry *ifdoffset = mRootIFD->getEntryRecursive(KODAK_IFD2);
    TiffIFD *kodakifd = NULL;
    try {
      if (mRootIFD->endian == getHostEndianness())
        kodakifd = new TiffIFD(mFile, ifdoffset->getInt());
      else
        kodakifd = new TiffIFDBE(mFile, ifdoffset->getInt());

     if (kodakifd && kodakifd->hasEntryRecursive(KODAK_KDC_WB)) {
        TiffEntry *wb = kodakifd->getEntryRecursive(KODAK_KDC_WB);
        if (wb->count == 3) {
          const uint32 *tmp = wb->getIntArray();
          mRaw->metadata.wbCoeffs[0] = (float)tmp[0];
          mRaw->metadata.wbCoeffs[1] = (float)tmp[1];
          mRaw->metadata.wbCoeffs[2] = (float)tmp[2];
        }
      }
    } catch(TiffParserException e) {
      mRaw->setError(e.what());
    }
    if (kodakifd)
      delete kodakifd;
  }

  // Use the normal WB if available
  if (mRootIFD->hasEntryRecursive(KODAKWB)) {
    TiffEntry *wb = mRootIFD->getEntryRecursive(KODAKWB);
    if (wb->count == 734 || wb->count == 1502) {
      const uchar8 *tmp = wb->getData();
      mRaw->metadata.wbCoeffs[0] = (float)((((ushort16) tmp[148])<<8)|tmp[149])/256.0f;
      mRaw->metadata.wbCoeffs[1] = 1.0f;
      mRaw->metadata.wbCoeffs[2] = (float)((((ushort16) tmp[150])<<8)|tmp[151])/256.0f;
    }
  }
}

void PefDecoder::decodeMetaData(CameraMetaData *meta) {
  int iso = 0;
  mRaw->cfa.setCFA(CFA_RED, CFA_GREEN, CFA_GREEN2, CFA_BLUE);
  vector<TiffIFD*> data = mRootIFD->getIFDsWithTag(MODEL);

  if (data.empty())
    ThrowRDE("PEF Meta Decoder: Model name found");

  TiffIFD* raw = data[0];

  string make = raw->getEntry(MAKE)->getString();
  string model = raw->getEntry(MODEL)->getString();

  if (mRootIFD->hasEntryRecursive(ISOSPEEDRATINGS))
    iso = mRootIFD->getEntryRecursive(ISOSPEEDRATINGS)->getInt();

  setMetaData(meta, make, model, "", iso);
}

RawImage ThreefrDecoder::decodeRawInternal() {
  vector<TiffIFD*> data = mRootIFD->getIFDsWithTag(STRIPOFFSETS);

  if (data.size() < 2)
    ThrowRDE("3FR Decoder: No image data found");

  TiffIFD* raw = data[1];
  uint32 width = raw->getEntry(IMAGEWIDTH)->getInt();
  uint32 height = raw->getEntry(IMAGELENGTH)->getInt();
  uint32 off = raw->getEntry(STRIPOFFSETS)->getInt();

  mRaw->dim = iPoint2D(width, height);
  mRaw->createData();
  ByteStream input(mFile->getData(off), mFile->getSize() - off);

  HasselbladDecompressor l(mFile, mRaw);
  map<string,string>::iterator pixelOffset = hints.find("pixelBaseOffset");
  if (pixelOffset != hints.end()) {
    stringstream convert((*pixelOffset).second);
    convert >> l.pixelBaseOffset;
  }

void Cr2Decoder::checkSupportInternal(CameraMetaData *meta) {
  vector<TiffIFD*> data = mRootIFD->getIFDsWithTag(MODEL);
  if (data.empty())
    ThrowRDE("CR2 Support check: Model name not found");
  if (!data[0]->hasEntry(MAKE))
    ThrowRDE("CR2 Support: Make name not found");
  string make = data[0]->getEntry(MAKE)->getString();
  string model = data[0]->getEntry(MODEL)->getString();

  // Check for sRaw mode
  data = mRootIFD->getIFDsWithTag((TiffTag)0xc5d8);
  if (!data.empty()) {
    TiffIFD* raw = data[0];
    if (raw->hasEntry((TiffTag)0xc6c5)) {
      ushort16 ss = raw->getEntry((TiffTag)0xc6c5)->getInt();
      if (ss == 4) {
        this->checkCameraSupported(meta, make, model, "sRaw1");
        return;
      }
    }
  }
  this->checkCameraSupported(meta, make, model, "");
}

void PefDecoder::decodeMetaDataInternal(CameraMetaData *meta) {
  int iso = 0;
  mRaw->cfa.setCFA(iPoint2D(2,2), CFA_RED, CFA_GREEN, CFA_GREEN2, CFA_BLUE);
  vector<TiffIFD*> data = mRootIFD->getIFDsWithTag(MODEL);

  if (data.empty())
    ThrowRDE("PEF Meta Decoder: Model name found");

  TiffIFD* raw = data[0];

  string make = raw->getEntry(MAKE)->getString();
  string model = raw->getEntry(MODEL)->getString();

  if (mRootIFD->hasEntryRecursive(ISOSPEEDRATINGS))
    iso = mRootIFD->getEntryRecursive(ISOSPEEDRATINGS)->getInt();

  setMetaData(meta, make, model, "", iso);

  // Read black level
  if (mRootIFD->hasEntryRecursive((TiffTag)0x200)) {
    TiffEntry *black = mRootIFD->getEntryRecursive((TiffTag)0x200);
    const ushort16 *levels = black->getShortArray();
    for (int i = 0; i < 4; i++)
      mRaw->blackLevelSeparate[i] = levels[i];
  }

  // Set the whitebalance
  if (mRootIFD->hasEntryRecursive((TiffTag) 0x0201)) {
    TiffEntry *wb = mRootIFD->getEntryRecursive((TiffTag) 0x0201);
    if (wb->count == 4) {
      const ushort16 *tmp = wb->getShortArray();
      mRaw->metadata.wbCoeffs[0] = tmp[0];
      mRaw->metadata.wbCoeffs[1] = tmp[1];
      mRaw->metadata.wbCoeffs[2] = tmp[3];
    }
  }
}

RawImage SrwDecoder::decodeRawInternal() {
  vector<TiffIFD*> data = mRootIFD->getIFDsWithTag(STRIPOFFSETS);

  if (data.empty())
    ThrowRDE("Srw Decoder: No image data found");

  TiffIFD* raw = data[0];

  int compression = raw->getEntry(COMPRESSION)->getInt();
  int bits = raw->getEntry(BITSPERSAMPLE)->getInt();

  if (32769 != compression && 32770 != compression )
    ThrowRDE("Srw Decoder: Unsupported compression");

  if (32769 == compression)
  {
    bool bit_order = false;  // Default guess
    map<string,string>::iterator msb_hint = hints.find("msb_override");
    if (msb_hint != hints.end())
      bit_order = (0 == (msb_hint->second).compare("true"));
    this->decodeUncompressed(raw, bit_order ? BitOrder_Jpeg : BitOrder_Plain);
    return mRaw;
  }

  if (32770 == compression)
  {
    bool bit_order = (bits == 12);  // Default guess
    map<string,string>::iterator msb_hint = hints.find("msb_override");
    if (msb_hint != hints.end())
      bit_order = (0 == (msb_hint->second).compare("true"));
    this->decodeUncompressed(raw, bit_order ? BitOrder_Jpeg : BitOrder_Plain);
    return mRaw;
  }
  ThrowRDE("Srw Decoder: Unsupported compression");
  return mRaw;
}

// readName will read the make and model of the image.
//
// If the name is read, it will return true, and the make/model
// will be available in camera_make/camera_model members.
boolean X3fDecoder::readName() {
  if (camera_make.length() != 0 && camera_model.length() != 0) {
    return ((boolean)TRUE);
  }

  // Read from properties
  if (hasProp("CAMMANUF") && hasProp("CAMMODEL")) {
    camera_make = getProp("CAMMANUF");
    camera_model = getProp("CAMMODEL");
    return ((boolean)TRUE);
  }

  // See if we can find EXIF info and grab the name from there.
  // This is needed for Sigma DP2 Quattro and possibly later cameras.
  vector<X3fImage>::iterator img = mImages.begin();
  for (; img !=  mImages.end(); img++) {
    X3fImage cimg = *img;
    if (cimg.type == 2 && cimg.format == 0x12 && cimg.dataSize > 100) {
      if (!mFile->isValid(cimg.dataOffset + cimg.dataSize - 1)) {
        return ((boolean)FALSE);
      }
      ByteStream i(mFile->getDataWrt(cimg.dataOffset), cimg.dataSize);
      // Skip jpeg header
      i.skipBytes(6);
      if (i.getInt() == 0x66697845) { // Match text 'Exif'
        TiffParser t(new FileMap(mFile->getDataWrt(cimg.dataOffset+12), i.getRemainSize()));
        try {
          t.parseData();
        } catch (...) {
          return ((boolean)FALSE);
        }
        TiffIFD *root = t.RootIFD();
        try {
          if (root->hasEntryRecursive(MAKE) && root->hasEntryRecursive(MODEL)) {
            camera_model = root->getEntryRecursive(MODEL)->getString();
            camera_make = root->getEntryRecursive(MAKE)->getString();
            mProperties.props["CAMMANUF"] = root->getEntryRecursive(MAKE)->getString();
            mProperties.props["CAMMODEL"] = root->getEntryRecursive(MODEL)->getString();
            return ((boolean)TRUE);
          }
        } catch (...) {}
        return ((boolean)FALSE);
      }
    }
  }
  return ((boolean)FALSE);
}

RawDecoder* TiffParser::getDecoder() {
    if (!mRootIFD)
        parseData();

    vector<TiffIFD*> potentials;
    potentials = mRootIFD->getIFDsWithTag(DNGVERSION);

    /* Copy, so we can pass it on and not have it destroyed with ourselves */
    TiffIFD* root = mRootIFD;

    if (!potentials.empty()) {  // We have a dng image entry
        TiffIFD *t = potentials[0];
        const unsigned char* c = t->getEntry(DNGVERSION)->getData();
        if (c[0] > 1)
            throw TiffParserException("DNG version too new.");
        mRootIFD = NULL;
        return new DngDecoder(root, mInput);
    }

    potentials = mRootIFD->getIFDsWithTag(MAKE);

    if (!potentials.empty()) {  // We have make entry
        for (vector<TiffIFD*>::iterator i = potentials.begin(); i != potentials.end(); ++i) {
            string make = (*i)->getEntry(MAKE)->getString();
            TrimSpaces(make);
            string model = "";
            if ((*i)->hasEntry(MODEL)) {
                model = (*i)->getEntry(MODEL)->getString();
                TrimSpaces(model);
            }
            if (!make.compare("Canon")) {
                mRootIFD = NULL;
                return new Cr2Decoder(root, mInput);
            }
            if (!make.compare("FUJIFILM")) {
                mRootIFD = NULL;
                return new RafDecoder(root, mInput);
            }
            if (!make.compare("NIKON CORPORATION")) {
                mRootIFD = NULL;
                return new NefDecoder(root, mInput);
            }
            if (!make.compare("NIKON")) {
                mRootIFD = NULL;
                return new NefDecoder(root, mInput);
            }
            if (!make.compare("OLYMPUS IMAGING CORP.") ||
                    !make.compare("OLYMPUS CORPORATION") ||
                    !make.compare("OLYMPUS OPTICAL CO.,LTD") ) {
                mRootIFD = NULL;
                return new OrfDecoder(root, mInput);
            }
            if (!make.compare("SONY")) {
                mRootIFD = NULL;
                return new ArwDecoder(root, mInput);
            }
            if (!make.compare("PENTAX Corporation") || !make.compare("RICOH IMAGING COMPANY, LTD.")) {
                mRootIFD = NULL;
                return new PefDecoder(root, mInput);
            }
            if (!make.compare("PENTAX")) {
                mRootIFD = NULL;
                return new PefDecoder(root, mInput);
            }
            if (!make.compare("Panasonic") || !make.compare("LEICA")) {
                mRootIFD = NULL;
                return new Rw2Decoder(root, mInput);
            }
            if (!make.compare("SAMSUNG")) {
                mRootIFD = NULL;
                return new SrwDecoder(root, mInput);
            }
            if (!make.compare("Mamiya-OP Co.,Ltd.")) {
                mRootIFD = NULL;
                return new MefDecoder(root, mInput);
            }
            if (!make.compare("Kodak")) {
                mRootIFD = NULL;
                if (!model.compare("DCS560C"))
                    return new Cr2Decoder(root, mInput);
                else
                    return new DcrDecoder(root, mInput);
            }
            if (!make.compare("KODAK")) {
                mRootIFD = NULL;
                return new DcsDecoder(root, mInput);
            }
            if (!make.compare("EASTMAN KODAK COMPANY")) {
                mRootIFD = NULL;
                return new KdcDecoder(root, mInput);
            }
            if (!make.compare("SEIKO EPSON CORP.")) {
                mRootIFD = NULL;
                return new ErfDecoder(root, mInput);
            }
            if (!make.compare("Hasselblad")) {
                mRootIFD = NULL;
                return new ThreefrDecoder(root, mInput);
            }
            if (!make.compare("Leaf")) {
//.........这里部分代码省略.........

RawImage NefDecoder::decodeRawInternal() {
  vector<TiffIFD*> data = mRootIFD->getIFDsWithTag(CFAPATTERN);

  if (data.empty())
    ThrowRDE("NEF Decoder: No image data found");

  TiffIFD* raw = data[0];
  int compression = raw->getEntry(COMPRESSION)->getInt();

  data = mRootIFD->getIFDsWithTag(MODEL);

  if (data.empty())
    ThrowRDE("NEF Decoder: No model data found");

  TiffEntry *offsets = raw->getEntry(STRIPOFFSETS);
  TiffEntry *counts = raw->getEntry(STRIPBYTECOUNTS);

  if (!data[0]->getEntry(MODEL)->getString().compare("NIKON D100 ")) {  /**Sigh**/
    if (!mFile->isValid(offsets->getInt()))
      ThrowRDE("NEF Decoder: Image data outside of file.");
    if (!D100IsCompressed(offsets->getInt())) {
      DecodeD100Uncompressed();
      return mRaw;
    }
  }

  if (compression == 1) {
    DecodeUncompressed();
    return mRaw;
  }

  if (offsets->count != 1) {
    ThrowRDE("NEF Decoder: Multiple Strips found: %u", offsets->count);
  }
  if (counts->count != offsets->count) {
    ThrowRDE("NEF Decoder: Byte count number does not match strip size: count:%u, strips:%u ", counts->count, offsets->count);
  }
  if (!mFile->isValid(offsets->getInt() + counts->getInt()))
    ThrowRDE("NEF Decoder: Invalid strip byte count. File probably truncated.");


  if (34713 != compression)
    ThrowRDE("NEF Decoder: Unsupported compression");

  uint32 width = raw->getEntry(IMAGEWIDTH)->getInt();
  uint32 height = raw->getEntry(IMAGELENGTH)->getInt();
  uint32 bitPerPixel = raw->getEntry(BITSPERSAMPLE)->getInt();

  mRaw->dim = iPoint2D(width, height);
  mRaw->createData();

  data = mRootIFD->getIFDsWithTag(MAKERNOTE);
  if (data.empty())
    ThrowRDE("NEF Decoder: No EXIF data found");

  TiffIFD* exif = data[0];
  TiffEntry *makernoteEntry = exif->getEntry(MAKERNOTE);
  const uchar8* makernote = makernoteEntry->getData();
  FileMap makermap((uchar8*)&makernote[10], mFile->getSize() - makernoteEntry->getDataOffset() - 10);
  TiffParser makertiff(&makermap);
  makertiff.parseData();

  data = makertiff.RootIFD()->getIFDsWithTag((TiffTag)0x8c);

  if (data.empty())
    ThrowRDE("NEF Decoder: Decompression info tag not found");

  TiffEntry *meta;
  try {
    meta = data[0]->getEntry((TiffTag)0x96);
  } catch (TiffParserException) {
    meta = data[0]->getEntry((TiffTag)0x8c);  // Fall back
  }

  try {
    NikonDecompressor decompressor(mFile, mRaw);

    ByteStream* metastream;
    if (getHostEndianness() == data[0]->endian)
      metastream = new ByteStream(meta->getData(), meta->count);
    else
      metastream = new ByteStreamSwap(meta->getData(), meta->count);

    decompressor.DecompressNikon(metastream, width, height, bitPerPixel, offsets->getInt(), counts->getInt());

    delete metastream;
  } catch (IOException &e) {
    mRaw->setError(e.what());
    // Let's ignore it, it may have delivered somewhat useful data.
  }

  return mRaw;
}

RawImage NefDecoder::decodeRawInternal() {
  vector<TiffIFD*> data = mRootIFD->getIFDsWithTag(CFAPATTERN);

  if (data.empty())
    ThrowRDE("NEF Decoder: No image data found");

  TiffIFD* raw = data[0];
  int compression = raw->getEntry(COMPRESSION)->getInt();

  data = mRootIFD->getIFDsWithTag(MODEL);

  if (data.empty())
    ThrowRDE("NEF Decoder: No model data found");

  TiffEntry *offsets = raw->getEntry(STRIPOFFSETS);
  TiffEntry *counts = raw->getEntry(STRIPBYTECOUNTS);

  if (!data[0]->getEntry(MODEL)->getString().compare("NIKON D100 ")) {  /**Sigh**/
    if (!mFile->isValid(offsets->getInt()))
      ThrowRDE("NEF Decoder: Image data outside of file.");
    if (!D100IsCompressed(offsets->getInt())) {
      DecodeD100Uncompressed();
      return mRaw;
    }
  }

  if (compression == 1 || (hints.find(string("force_uncompressed")) != hints.end()) ||
      NEFIsUncompressed(raw)) {
    DecodeUncompressed();
    return mRaw;
  }

  if (NEFIsUncompressedRGB(raw)) {
    DecodeSNefUncompressed();
    return mRaw;
  }

  if (offsets->count != 1) {
    ThrowRDE("NEF Decoder: Multiple Strips found: %u", offsets->count);
  }
  if (counts->count != offsets->count) {
    ThrowRDE("NEF Decoder: Byte count number does not match strip size: count:%u, strips:%u ", counts->count, offsets->count);
  }
  if (!mFile->isValid(offsets->getInt(), counts->getInt()))
    ThrowRDE("NEF Decoder: Invalid strip byte count. File probably truncated.");


  if (34713 != compression)
    ThrowRDE("NEF Decoder: Unsupported compression");

  uint32 width = raw->getEntry(IMAGEWIDTH)->getInt();
  uint32 height = raw->getEntry(IMAGELENGTH)->getInt();
  uint32 bitPerPixel = raw->getEntry(BITSPERSAMPLE)->getInt();

  mRaw->dim = iPoint2D(width, height);
  mRaw->createData();

  data = mRootIFD->getIFDsWithTag((TiffTag)0x8c);

  if (data.empty())
    ThrowRDE("NEF Decoder: Decompression info tag not found");

  TiffEntry *meta;
  if (data[0]->hasEntry((TiffTag)0x96)) {
    meta = data[0]->getEntry((TiffTag)0x96);
  } else {
    meta = data[0]->getEntry((TiffTag)0x8c);  // Fall back
  }

  try {
    NikonDecompressor decompressor(mFile, mRaw);
    decompressor.uncorrectedRawValues = uncorrectedRawValues;
    ByteStream* metastream;
    if (getHostEndianness() == data[0]->endian)
      metastream = new ByteStream(meta->getData(), meta->count);
    else
      metastream = new ByteStreamSwap(meta->getData(), meta->count);

    decompressor.DecompressNikon(metastream, width, height, bitPerPixel, offsets->getInt(), counts->getInt());

    delete metastream;
  } catch (IOException &e) {
    mRaw->setError(e.what());
    // Let's ignore it, it may have delivered somewhat useful data.
  }

  return mRaw;
}

RawImage Rw2Decoder::decodeRawInternal() {

  vector<TiffIFD*> data = mRootIFD->getIFDsWithTag(PANASONIC_STRIPOFFSET);

  bool isOldPanasonic = FALSE;

  if (data.empty()) {
    if (!mRootIFD->hasEntryRecursive(STRIPOFFSETS))
      ThrowRDE("RW2 Decoder: No image data found");
    isOldPanasonic = TRUE;
    data = mRootIFD->getIFDsWithTag(STRIPOFFSETS);
  }

  TiffIFD* raw = data[0];
  uint32 height = raw->getEntry((TiffTag)3)->getShort();
  uint32 width = raw->getEntry((TiffTag)2)->getShort();

  if (isOldPanasonic) {
    ThrowRDE("Cannot decode old-style Panasonic RAW files");
    TiffEntry *offsets = raw->getEntry(STRIPOFFSETS);
    TiffEntry *counts = raw->getEntry(STRIPBYTECOUNTS);

    if (offsets->count != 1) {
      ThrowRDE("RW2 Decoder: Multiple Strips found: %u", offsets->count);
    }
    int off = offsets->getInt();
    if (!mFile->isValid(off))
      ThrowRDE("Panasonic RAW Decoder: Invalid image data offset, cannot decode.");

    int count = counts->getInt();
    if (count != (int)(width*height*2))
      ThrowRDE("Panasonic RAW Decoder: Byte count is wrong.");

    if (!mFile->isValid(off+count))
      ThrowRDE("Panasonic RAW Decoder: Invalid image data offset, cannot decode.");
      
    mRaw->dim = iPoint2D(width, height);
    mRaw->createData();
    ByteStream input_start(mFile->getData(off), mFile->getSize() - off);
    iPoint2D pos(0, 0);
    readUncompressedRaw(input_start, mRaw->dim,pos, width*2, 16, BitOrder_Plain);

  } else {

    mRaw->dim = iPoint2D(width, height);
    mRaw->createData();
    TiffEntry *offsets = raw->getEntry(PANASONIC_STRIPOFFSET);

    if (offsets->count != 1) {
      ThrowRDE("RW2 Decoder: Multiple Strips found: %u", offsets->count);
    }

    load_flags = 0x2008;
    int off = offsets->getInt();

    if (!mFile->isValid(off))
      ThrowRDE("RW2 Decoder: Invalid image data offset, cannot decode.");

    input_start = new ByteStream(mFile->getData(off), mFile->getSize() - off);
    DecodeRw2();
  }
  // Read blacklevels
  if (raw->hasEntry((TiffTag)0x1c) && raw->hasEntry((TiffTag)0x1d) && raw->hasEntry((TiffTag)0x1e)) {
    mRaw->blackLevelSeparate[0] = raw->getEntry((TiffTag)0x1c)->getInt() + 15;
    mRaw->blackLevelSeparate[1] = mRaw->blackLevelSeparate[2] = raw->getEntry((TiffTag)0x1d)->getInt() + 15;
    mRaw->blackLevelSeparate[3] = raw->getEntry((TiffTag)0x1e)->getInt() + 15;
  }
  return mRaw;
}

RawDecoder* TiffParser::getDecoder() {
  if (!mRootIFD)
    parseData();

  vector<TiffIFD*> potentials;
  potentials = mRootIFD->getIFDsWithTag(DNGVERSION);

  /* Copy, so we can pass it on and not have it destroyed with ourselves */
  TiffIFD* root = mRootIFD;

  if (!potentials.empty()) {  // We have a dng image entry
    TiffIFD *t = potentials[0];
    const unsigned char* c = t->getEntry(DNGVERSION)->getData();
    if (c[0] > 1)
      throw TiffParserException("DNG version too new.");
    mRootIFD = NULL;
    return new DngDecoder(root, mInput);
  }

  potentials = mRootIFD->getIFDsWithTag(MAKE);

  if (!potentials.empty()) {  // We have make entry
    for (vector<TiffIFD*>::iterator i = potentials.begin(); i != potentials.end(); ++i) {
      string make = (*i)->getEntry(MAKE)->getString();
      TrimSpaces(make);
      if (!make.compare("Canon")) {
        mRootIFD = NULL;
        return new Cr2Decoder(root, mInput);
      }
      if (!make.compare("NIKON CORPORATION")) {
        mRootIFD = NULL;
        return new NefDecoder(root, mInput);
      }
      if (!make.compare("NIKON")) {
        mRootIFD = NULL;
        return new NefDecoder(root, mInput);
      }
      if (!make.compare("OLYMPUS IMAGING CORP.")) {
        mRootIFD = NULL;
        return new OrfDecoder(root, mInput);
      }
      if (!make.compare("SONY")) {
        mRootIFD = NULL;
        return new ArwDecoder(root, mInput);
      }
      if (!make.compare("PENTAX Corporation ")) {
        mRootIFD = NULL;
        return new PefDecoder(root, mInput);
      }
      if (!make.compare("PENTAX")) {
        mRootIFD = NULL;
        return new PefDecoder(root, mInput);
      }
      if (!make.compare("Panasonic")) {
        mRootIFD = NULL;
        return new Rw2Decoder(root, mInput);
      }
      if (!make.compare("SAMSUNG")) {
        mRootIFD = NULL;
        return new SrwDecoder(root, mInput);
      }
    }
  }
  throw TiffParserException("No decoder found. Sorry.");
  return NULL;
}