ITEM: Inter-Texture Error Measurement for 3D Meshes

We introduce a simple and innovative method to compare any two texture maps, regardless of their sizes, aspect ratios, or even masks, as long as they are both meant to be mapped onto the same 3D mesh. Our system is based on a zero-distortion 3D mesh unwrapping technique which compares two new adapted texture atlases with the same mask but different texel colors, and whose every texel covers the same area in 3D. Once these adapted atlases are created, we measure their difference with ITEM-RMSE, a slightly modified version of the standard RMSE defined for images. ITEM-RMSE is more meaningful and reliable than RMSE because it only takes into account the texels inside the mask, since they are the only ones that will actually be used during rendering. Our method is not only very useful to compare the space efficiency of different texture atlas generation algorithms, but also to quantify texture loss in compression schemes for multi-resolution textured 3D meshes.

Military Districts, England and Wales, United Kingdom, 1804 (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: A complete representation of the coast of England, together with the interior, divided into counties and military districts : also the coast of France and Holland from the Texel to Brest ... to which is annexed eighteen plans of the ports of the enemy, the principal depôts of the flotilla intended for the invasion of England, by John Luffman, Geogr. It was published by J. Luffman in 1804. Scale [ca. 1:2,500,000]. The image inside the map neatline is georeferenced to the surface of the earth and fit to the 'British National Grid' coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, administrative and military district boundaries, shoreline features including distances between selected ports, and more. Includes insets of foreign military installations and index to the military districts. This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.