Image Tiling

When exporting an image from Deep Zoom Composer at design-time, each image in the composition is partitioned (or sliced) into tiles. During the tiling process, an image pyramid is created of various resolutions. At the base of the pyramid sits the highest-resolution image, composed of multiple tiles, and at the top of the pyramid is a single tile, the lowest resolution image (see Figure 7.8).

FIGURE 7.8 Image tiling (image from MSDN).

The tiles produced by Deep Zoom Composer are supposed to be 256 by 256 pixels. I found, however, that the nominal tile size is 258 by 258 pixels. Each zoom level is scaled by a factor of two compared to the level above. However, most images won’t come in multiples of 258 pixels, and the resulting tile sets will usually contain many tiles with fewer than 258 pixels in width or height.