Exiv2

Hello,

we've tried to use exiv2 for reading and writing thumbs (windows7, msvc compiler). although the reading of thumbnails works fine, we've problems if the thumbnails doesn't exist and we try to create a new one. writeMetaData throws an exception in tiffimage.cpp, line 1853 (io.transfer(*tempio). the complete code for the writing of the thumbs is listed below. it seems that the temporary file is locked. the exception is thrown in basicio.cpp, line 635 (called by transfer). The Error Code of "DeleteFile" is 32. it doesn't matter if the file is a tif file or another kind of image type.
we've tried the last official release as well as the trunk version. thank you for any help.

kind regards,

florian

    Exiv2::ExifData exifData = exifImg->exifData();

    if (exifData.empty()) {
        DkUtils::printDebug(DK_MODULE, "exif data is empty\n");
        exifData = Exiv2::ExifData();
    }

    // ok, let's try to save the thumbnail...
    try {

        Exiv2::ExifThumb eThumb(exifData);

        if (isTiff()) {
            eThumb.erase();

            Exiv2::ExifData::const_iterator pos = exifData.findKey(Exiv2::ExifKey("Exif.Image.NewSubfileType"));
            if (pos == exifData.end() || pos->count() != 1 || pos->toLong() != 0) {
                 throw DkException("Exif.Image.NewSubfileType missing or not set as main image", __LINE__, __FILE__);
             }
             std::string subImage1("SubImage1");
             for (Exiv2::ExifData::iterator md = exifData.begin(); md != exifData.end();)
             {
                 if (md->groupName() == subImage1)
                     md = exifData.erase(md);
                 else
                     ++md;
             }
        }

        QByteArray data;
        QBuffer buffer(&data);
        buffer.open(QIODevice::WriteOnly);
        thumb.save(&buffer, "JPEG");

        if (isTiff()) {
            Exiv2::DataBuf buf((Exiv2::byte *)data.data(), data.size());
            Exiv2::ULongValue val;
            val.read("0");
            val.setDataArea(buf.pData_, buf.size_);
            exifData["Exif.SubImage1.JPEGInterchangeFormat"] = val;
            exifData["Exif.SubImage1.JPEGInterchangeFormatLength"] = uint32_t(buf.size_);
            exifData["Exif.SubImage1.Compression"] = uint16_t(6); // JPEG (old-style)
            exifData["Exif.SubImage1.NewSubfileType"] = uint32_t(1); // Thumbnail image
            DkUtils::printDebug(DK_MODULE, "As you told me to, I am writing the tiff thumbs...\n");

        } else {
            eThumb.setJpegThumbnail((Exiv2::byte *)data.data(), data.size());
            DkUtils::printDebug(DK_MODULE, "As you told me to, I am writing the thumbs...\n");
        }

        exifImg->setExifData(exifData);
        exifImg->writeMetadata();