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Averaged Dimension of Computer Graphics
Figure 3: The histogram of the average dimension of the PRCG set
2. Natural secne content scope: Similar to the PIM image sets, the
content of the images is limited to natural scene only. By setting this
scope, many of the abstract or fantastic scene PRCG are excluded.
3. Image size: The size of the PRCG varies between 400 pixels and
1400 pixels in average dimension, (width + height)/2, with the mean
at 645 pixels. Figure 3 shows the histogram of the average dimension
of the PRCG set.
4. High photorealism: The images are visually inspected by the au-
thors to ensure their high photorealism. Incidentally, from the avail-
able rendering information of the PRCG set, we can see that the PRCG
images often have high quality rendering effect such as global illumi-
nation, caustics effects, or camera effect like depth of field (DoF).
5. Record of the rendering information: The associated rendering
information for the PRCG is recorded during the collection process
whenever it is available. See Section 4.1 for more details.
6. Category: The PRCG are categorized according to its content type.
More details in Section 4.2.
7. Post-processing: The white border or text at the corners are cropped
out and the PRCG duplicates are removed.
9