Living Virtually: Creating and Interfacing Digital Surrogates of Textual Data Embedded (Hidden) in Cultural Heritage Artefacts

自从18世纪在赫库兰尼姆发现碳化纸莎草纸以来，人们一直对访问卷轴中包含的内容非常感兴趣，这些卷轴由公元79年维苏威火山喷发的高温保存下来。最初打开这些卷轴的尝试是用刀手工进行的，但这导致它们破碎成碎片。随后在1756年发明了一种机器，以创造一种更安全的展开方法，这种方法更成功地应用于许多卷轴。然而，在许多情况下，不同层的纸莎草纸不可能相互粘连，因此即使成功打开卷轴，大部分文本也会隐藏在其中，而数百卷卷轴仍然过于牢固地碳化，根本无法展开。这些完好无损的卷轴的内容，以及粘贴层下的文本内容仍然是一个谜。新技术提供了一种解决方案。在21世纪初，无创CT扫描的应用，一个已经被项目成员证明的概念，揭示了新的可能性。卷轴的结构可以在三维中以数字方式呈现，揭示了卷轴周围的纸莎草层。在过去的十年中，项目成员开发了算法上分离、展开和展平这些层的计算方法。该虚拟展开方法已成功地应用于P.Herc。375和495。然而，尽管取得了这样的成就，墨水看起来并没有明显的清晰度。虽然一些希腊字母的微弱痕迹已经被转录，但目前还没有手段来验证和复制这些结果。该项目旨在解决在这种非侵入性成像中检测墨水的问题，从而彻底解决Herculaneum Papyri带来的长期问题。2016年，项目成员成功地将虚拟展开方法应用于以色列Ein Gedi遗址的一幅碳化希伯来语卷轴。墨水立即可见，但这是因为它被重微量元素污染，因此自然出现在CT扫描中。Herculaneum Papyri中使用的碳基墨水不能以同样的方式可视化。然而，我们现在知道，墨水被铅污染得很弱。因此，我们提出了一种新的方法，称为暗场X射线成像。这揭示了墨水通过分离和捕获其组成中的痕量元素，如铅。为了进一步增强生成的墨迹信号，我们引入了一种名为参考放大计算机层析成像(RACT)的新神经网络来放大墨迹的存在和希腊字符的形状，以提高易读性。这种方法将彻底解决隐藏在Herculaneum Papyri中的文本的阅读问题。为了增加价值，该项目将通过开发一个新的数字平台--文化参与增强语言界面(ALICE)，使研究人员和负责这些文物的馆长能够获取这一过程产生的数据，确保暗场X射线成像和RACT过程产生的数据可以访问，可以适当地管理，提取的文本可以进行数字编辑。此外，Alice还包括集成原始人工制品的3D模型和记录元数据的功能，元数据解释了文本是如何创建的，以及文本在与其数字版本一起生成的模型中来自对象的几何图形中的哪里。这对于科学地核实和复制任何随后的数据分析或出版是必要的。值得注意的是，对于包含隐藏文本的其他文化遗产文物，我们的新成像技术和数字平台将使用开放的建筑标准构建；源代码将很容易适应对其他难以处理的文物中文字的非侵入性阅读，例如烧毁的书籍、书籍装订和木乃伊纸箱。

Since the discovery of the carbonised papyri at Herculaneum in the 18th century, there has been a great deal of interest in accessing the content contained in the scrolls preserved by the intense heat from the eruption of Mount Vesuvius in 79 CE. The first attempts to open these scrolls were made by hand using a knife, but this caused them to break into fragmented chunks. Subsequently in 1756 a machine was invented to create a safer method of unrolling, which was more successfully applied to numerous scrolls. However, in many cases it was impossible to keep the different layers of papyrus from sticking to each other, and so substantial portions of text remained hidden in even successfully opened scrolls, while hundreds of scrolls remained too firmly carbonised to unroll at all. The content of these fully intact scrolls, together with that of text under the stuck-on layers remains a mystery. New technology offers a solution. In the early 21st century the application of non-invasive CT scanning, a concept already proved by project members, reveals new possibilities. The structure of a scroll can be rendered digitally in three dimensions, revealing the layers of the papyrus in the scroll's circumference. Computational methods for algorithmically separating, unrolling, and flattening these layers have been developed by project members over the past decade. The virtual unrolling method has been successfully applied to P. Herc. 375 and 495. Nevertheless, despite such an achievement, the ink does not appear with any significant clarity. And while faint traces of a handful of Greek letters have been transcribed, there is currently no means to verify and replicate such results.This project aims to address the problem of detecting ink in this non-invasive imaging and thus definitively solve the long-standing problem posed by the Herculaneum papyri. In 2016 project members successfully applied the virtual unrolling method to a carbonised Hebrew scroll from the site of Ein Gedi in Israel. The ink was immediately visible, but this was due to the fact that it was contaminated with heavy trace elements and thus naturally appeared in CT scanning. The carbon-based ink used in Herculaneum papyri cannot be visualised in the same way. However, we now know that the ink is weakly contaminated with lead. We thus propose a new method called Dark Field X-ray Imaging. This reveals ink by isolating and capturing trace elements, such as lead, in its composition. To enhance the resulting ink signal further we introduce a new neural network called Reference-Amplified Computed Tomography (RACT) to amplify both the ink's presence and the shapes of the Greek characters for improved legibility. This method will definitively solve the problem of reading the text hidden in the Herculaneum papyri. To add value, the project will make the data generated by this process accessible to researchers and the curators responsible for these artefacts, by developing a new digital platform, the Augmented Language Interface for Cultural Engagement (ALICE), ensuring that the data produced by the Dark Field X-ray Imaging and RACT processes is accessible, can be properly curated, and that the extracted text can be digitally edited. Moreover, ALICE includes the functionality for integrating 3D models of the original artefact and for recording the metadata that explains both how the text was created and from where in the object's geometry the text originates in the model generated along with its digital edition. This is necessary for scientifically verifying and replicating any subsequent analysis or publication of the data. Significantly, for other cultural heritage artefacts that contain hidden text, our new imaging techniques and digital platform will be built using open architecture standards; the source code will be easily adaptable for non-invasive reading of writing inside other intractable artefacts, such as burnt books, book-bindings, and mummy cartonnage.