C++ ExifData::erase方法代码示例

static void EraseGpsTags(Exiv2::ExifData &ExifInfo)
{
	// Search through, find the keys that we want, and wipe them
	// Code below submitted by Marc Horowitz
	Exiv2::ExifData::iterator Iter;
	for (Exiv2::ExifData::iterator Iter = ExifInfo.begin();
		Iter != ExifInfo.end(); )
	{
		if (Iter->key().find("Exif.GPSInfo") == 0)
			Iter = ExifInfo.erase(Iter);
		else
			Iter++;
	}
}

void clearGPSFields(Exiv2::ExifData &exifData) {
    std::list<std::string> fields = {"Exif.GPSInfo.GPSLatitude",
                                     "Exif.GPSInfo.GPSLongitude",
                                     "Exif.GPSInfo.GPSMapDatum",
                                     "Exif.GPSInfo.GPSLatitudeRef",
                                     "Exif.GPSInfo.GPSLongitudeRef",
                                     "Exif.GPSInfo.GPSLatitude",
                                     "Exif.GPSInfo.GPSLongitude",
                                     
                                     "Exif.GPSInfo.GPSAltitude",
                                     "Exif.GPSInfo.GPSAltitudeRef",

                                     "Exif.GPSInfo.GPSTimeStamp",
                                     "Exif.GPSInfo.GPSDateStamp",};
    for (auto fname : fields) {
        auto key = Exiv2::ExifKey(fname.c_str());
        auto iter = exifData.findKey(key);
        while (iter != exifData.end()) {
            exifData.erase(iter);
            iter = exifData.findKey(key);
        }
    }
}

bool ptImageHelper::WriteExif(const QString              &AFileName,
                              const std::vector<uint8_t> &AExifBuffer,
                              Exiv2::IptcData            &AIptcData,
                              Exiv2::XmpData             &AXmpData) {
  try {
#if EXIV2_TEST_VERSION(0,17,91)   /* Exiv2 0.18-pre1 */

    Exiv2::ExifData hInExifData;

    Exiv2::ExifParser::decode(hInExifData,
                              AExifBuffer.data() + CExifHeader.size(),
                              AExifBuffer.size() - CExifHeader.size());

    // Reset orientation
    Exiv2::ExifData::iterator pos = hInExifData.begin();
    if ((pos = hInExifData.findKey(Exiv2::ExifKey("Exif.Image.Orientation"))) != hInExifData.end()) {
      pos->setValue("1"); // Normal orientation
    }

    // Adapted from UFRaw, necessary for Tiff files
    QStringList ExifKeys;
    ExifKeys  << "Exif.Image.ImageWidth"
              << "Exif.Image.ImageLength"
              << "Exif.Image.BitsPerSample"
              << "Exif.Image.Compression"
              << "Exif.Image.PhotometricInterpretation"
              << "Exif.Image.FillOrder"
              << "Exif.Image.SamplesPerPixel"
              << "Exif.Image.StripOffsets"
              << "Exif.Image.RowsPerStrip"
              << "Exif.Image.StripByteCounts"
              << "Exif.Image.XResolution"
              << "Exif.Image.YResolution"
              << "Exif.Image.PlanarConfiguration"
              << "Exif.Image.ResolutionUnit";

    for (short i = 0; i < ExifKeys.count(); i++) {
      if ((pos = hInExifData.findKey(Exiv2::ExifKey(ExifKeys.at(i).toLocal8Bit().data()))) != hInExifData.end())
        hInExifData.erase(pos);
    }

    if (Settings->GetInt("EraseExifThumbnail")) {
      Exiv2::ExifThumb Thumb(hInExifData);
      Thumb.erase();
    }

    QStringList JpegExtensions;
    JpegExtensions << "jpg" << "JPG" << "Jpg" << "jpeg" << "Jpeg" << "JPEG";
    bool deleteDNGdata = false;
    for (short i = 0; i < JpegExtensions.count(); i++) {
      if (!AFileName.endsWith(JpegExtensions.at(i))) deleteDNGdata = true;
    }

    Exiv2::Image::AutoPtr Exiv2Image = Exiv2::ImageFactory::open(AFileName.toLocal8Bit().data());

    Exiv2Image->readMetadata();
    Exiv2::ExifData outExifData = Exiv2Image->exifData();

    for (auto hPos = hInExifData.begin(); hPos != hInExifData.end(); hPos++) {
      if (!deleteDNGdata || (*hPos).key() != "Exif.Image.DNGPrivateData") {
        outExifData.add(*hPos);
      }
    }

    // IPTC data

    QStringList Tags        = Settings->GetStringList("TagsList");
    QStringList DigikamTags = Settings->GetStringList("DigikamTagsList");

    Exiv2::StringValue StringValue;
    for (int i = 0; i < Tags.size(); i++) {
      StringValue.read(Tags.at(i).toStdString());
      AIptcData.add(Exiv2::IptcKey("Iptc.Application2.Keywords"), &StringValue);
    }


    // XMP data

    for (int i = 0; i < Tags.size(); i++) {
      AXmpData["Xmp.dc.subject"] = Tags.at(i).toStdString();
    }
    for (int i = 0; i < DigikamTags.size(); i++) {
      AXmpData["Xmp.digiKam.TagsList"] = DigikamTags.at(i).toStdString();
    }

    // Image rating
    outExifData["Exif.Image.Rating"] = Settings->GetInt("ImageRating");
    AXmpData["Xmp.xmp.Rating"]       = Settings->GetInt("ImageRating");

    // Program name
    outExifData["Exif.Image.ProcessingSoftware"]  = ProgramName;
    outExifData["Exif.Image.Software"]            = ProgramName;
    AIptcData["Iptc.Application2.Program"]        = ProgramName;
    AIptcData["Iptc.Application2.ProgramVersion"] = "idle";
    AXmpData["Xmp.xmp.CreatorTool"]               = ProgramName;
    AXmpData["Xmp.tiff.Software"]                 = ProgramName;

    // Title
    QString TitleWorking = Settings->GetString("ImageTitle");
    StringClean(TitleWorking);
//.........这里部分代码省略.........

// *****************************************************************************
// Main
int main()
try {
    // Container for all metadata
    Exiv2::ExifData exifData;

    // *************************************************************************
    // Add to the Exif data

    // Create a ASCII string value (note the use of create)
    Exiv2::Value* v = Exiv2::Value::create(Exiv2::asciiString);
    // Set the value to a string
    v->read("1999:12:31 23:59:59");
    // Add the value together with its key to the Exif data container
    Exiv2::ExifKey key("Exif.Photo.DateTimeOriginal");
    exifData.add(key, v);

    std::cout << "Added key \"" << key << "\", value \"" << *v << "\"\n";
    // Delete the memory allocated by Value::create
    delete v;

    // Now create a more interesting value (without using the create method)
    Exiv2::URationalValue* rv = new Exiv2::URationalValue;
    // Set two rational components from a string
    rv->read("1/2 1/3");
    // Add more elements through the extended interface of rational value 
    rv->value_.push_back(std::make_pair(2,3));
    rv->value_.push_back(std::make_pair(3,4));
    // Add the key and value pair to the Exif data
    key = Exiv2::ExifKey("Exif.Image.PrimaryChromaticities");
    exifData.add(key, rv);

    std::cout << "Added key \"" << key << "\", value \"" << *rv << "\"\n";
    // Delete memory allocated on the heap
    delete rv;

    // *************************************************************************
    // Modify Exif data

    // Find the timestamp metadatum by its key
    key = Exiv2::ExifKey("Exif.Photo.DateTimeOriginal");
    Exiv2::ExifData::iterator pos = exifData.findKey(key);
    if (pos == exifData.end()) throw Exiv2::Error("Key not found");
    // Modify the value
    std::string date = pos->toString();
    date.replace(0,4,"2000");
    pos->setValue(date); 
    std::cout << "Modified key \"" << key 
              << "\", new value \"" << pos->value() << "\"\n";

    // Find the other key
    key = Exiv2::ExifKey("Exif.Image.PrimaryChromaticities");
    pos = exifData.findKey(key);
    if (pos == exifData.end()) throw Exiv2::Error("Key not found");
    // Get a pointer to a copy of the value
    v = pos->getValue();
    // Downcast the Value pointer to its actual type
    rv = dynamic_cast<Exiv2::URationalValue*>(v);
    if (rv == 0) throw Exiv2::Error("Downcast failed");
    // Modify the value directly through the interface of URationalValue
    rv->value_[2] = std::make_pair(88,77);
    // Copy the modified value back to the metadatum
    pos->setValue(rv);
    // Delete the memory allocated by getValue
    delete v;
    std::cout << "Modified key \"" << key 
              << "\", new value \"" << pos->value() << "\"\n";

    // *************************************************************************
    // Delete metadata from the Exif data container

    // Delete the metadatum at iterator position pos
    key = Exiv2::ExifKey("Exif.Image.PrimaryChromaticities");
    pos = exifData.findKey(key);
    if (pos == exifData.end()) throw Exiv2::Error("Key not found");
    exifData.erase(pos);
    std::cout << "Deleted key \"" << key << "\"\n";

    // *************************************************************************
    // Finally, write the remaining Exif data to an image file
    int rc = exifData.write("img_2158.jpg");
    if (rc) {
        std::string error = Exiv2::ExifData::strError(rc, "img_2158.jpg");
        throw Exiv2::Error(error);
    }

    return 0;
}
catch (Exiv2::Error& e) {
    std::cout << "Caught Exiv2 exception '" << e << "'\n";
    return -1;
}

bool ptImageHelper::ReadExif(const QString        &AFileName,
                             Exiv2::ExifData      &AExifData,
                             std::vector<uint8_t> &AExifBuffer)
{
  if (AFileName.trimmed().isEmpty()) return false;

  try {
    if (Exiv2::ImageFactory::getType(AFileName.toLocal8Bit().data()) == Exiv2::ImageType::none)
      return false;

    Exiv2::Image::AutoPtr hImage = Exiv2::ImageFactory::open(AFileName.toLocal8Bit().data());

    if (!hImage.get()) return false;

    hImage->readMetadata();

    AExifData = hImage->exifData();
    if (AExifData.empty()) {
      ptLogWarning(ptWarning_Argument, "No Exif data found in %s", AFileName.toLocal8Bit().data());
      return false;
    }

    Exiv2::ExifData::iterator Pos;
    size_t                    Size;

#if EXIV2_TEST_VERSION(0,17,91)   /* Exiv2 0.18-pre1 */
    Exiv2::Blob               Blob;
    Exiv2::ExifParser::encode(Blob, Exiv2::bigEndian, AExifData);
    Size = Blob.size();
#else
    Exiv2::DataBuf            Buf(AExifData.copy());
    Size = Buf.size_;
#endif

    /* If buffer too big for JPEG, try deleting some stuff. */
    if (Size + CExifHeader.size() > CMaxHeaderLength) {
      if ((Pos = AExifData.findKey(Exiv2::ExifKey("Exif.Photo.MakerNote"))) != AExifData.end() ) {
        AExifData.erase(Pos);
        ptLogWarning(ptWarning_Argument, "Exif buffer too big, erasing Exif.Photo.MakerNote");
#if EXIV2_TEST_VERSION(0,17,91)   /* Exiv2 0.18-pre1 */
        Exiv2::ExifParser::encode(Blob, Exiv2::bigEndian, AExifData);
        Size = Blob.size();
#else
        Buf  = AExifData.copy();
        Size = Buf.size_;
#endif
      }
    }

    // Erase embedded thumbnail if needed
    if (Settings->GetInt("EraseExifThumbnail") ||
        (Size + CExifHeader.size()) > CMaxHeaderLength ) {
#if EXIV2_TEST_VERSION(0,17,91)   /* Exiv2 0.18-pre1 */
      Exiv2::ExifThumb Thumb(AExifData);
      Thumb.erase();
#else
      AExifData.eraseThumbnail();
#endif

      if (!Settings->GetInt("EraseExifThumbnail"))
        ptLogWarning(ptWarning_Argument, "Exif buffer too big, erasing Thumbnail");

#if EXIV2_TEST_VERSION(0,17,91)   /* Exiv2 0.18-pre1 */
      Exiv2::ExifParser::encode(Blob, Exiv2::bigEndian, AExifData);
      Size = Blob.size();
#else
      Buf = AExifData.copy();
      Size = Buf.size_;
#endif
    }

    AExifBuffer.clear();
    AExifBuffer.insert(AExifBuffer.end(),
                       CExifHeader.begin(),
                       CExifHeader.end());
#if EXIV2_TEST_VERSION(0,17,91)   /* Exiv2 0.18-pre1 */
    AExifBuffer.insert(AExifBuffer.end(),
                       Blob.begin(),
                       Blob.end());
#else
    // old code will currently not compile
    memcpy(AExifBuffer+sizeof(ExifHeader), Buf.pData_, Buf.size_);
#endif
    return true;

  } catch(Exiv2::Error& Error) {
    // Exiv2 errors are in this context hopefully harmless
    // (unsupported tags etc.)

    ptLogWarning(ptWarning_Exiv2,"Exiv2 : %s\n",Error.what());
  }
  return false;
}