Page 204 - DCAP504_Computer Graphics

Unit 13: Advanced Computer Graphics

The following figure 13.6 depicts the various stages (a, b, c and d) of unwrapping the cuneiform tablets.

Figure 13.6: Cuneiform Unwrapping

Source: http://graphics.stanford.edu/papers/cuneiform/cuneiform-300dpi-images.pdf
Now, let us discuss about various stages found in above figure 13.6:
(a) Tablet: A photograph of an Ur III dynasty cuneiform tablet (from 2100 BC).
(b) 3-D Model: A Phong-shaded rendering of a 50-micron resolution 3-D model containing 3.2
million triangles.
(c) Relief: The writing is unwrapped and shown as a displacement map.
(d) Shading: The unwrapped inscriptions have been accessibility colored, curvature colored, and
rendered using phong shading to enhance readability.

The issue with limitations of photography was solved with the help of a high resolution 3-D computer
model from laser range data. The image is unwrapped by flattening the inscriptions found on the model
to a plane. This is represented as a scalar displacement map as shown in figure 10.6 (c). Finally, the
scalar displacement map is rendered non-photo realistically by using accessibility and curvature
coloring. The output from this semi-automatic process enables to perceive the tablet’s text in a single
concise image.

The unwrapping techniques are also applied to other types of inscribed surfaces such as bas-reliefs.
The cuneiform inscriptions are believed to be the first written inscriptions and were made in moist clay
tablets. These tablets were made before 3,500 BC. It has been found that more than 1, 00,000 tablets exist
to this day in disintegrated state. The size of these cuneiform tablets ranges from 2 to 12 centimeters.
These cuneiform tablets contain data relating to historic events and transactions of the past. The texts on
these tablets are pictograms and hence are difficult to translate to texts.

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