Digital Photographer's Software Guide - Bertemes - Net

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The Digital Photographer's Software Guide
Stitching dozens of overlapping pictures together can be time-consuming unless the
stitching software can do much of the work automatically. This is something that computers
are very good at—detecting unique groups of pixels and identifying them as control
points. It is much easier for a computer than for the human eye, so you should
ensure that the software has an excellent auto-stitching mode before committing to it.
Commercial software for real estate suppliers cannot normally have the luxury of using
too many images for each panorama. It would take far too long to acquire the input.
Hardware companies have invented other ways of solving this problem: for example by
“one-shot” camera systems that use a 360-degree mirror to capture the entire scene in
a single take. More common is the use of fisheye lenses to take either two or three (three
is better) hemispherical shots that can be stitched together to make a complete
panorama. The fewer images you have to input to the software, the faster it will generate
the output.
Virtual Tours
For creating virtual tours, software requires many additional features. It links together
panoramas of (for example) individual rooms to give the impression that the viewer is
taking a walk around the building. It may also add other information, in text or video,
plus a soundtrack. There is really no limit to the degree of complexity you can introduce
into a full multimedia presentation. Most companies package their stitching software
separately from their virtual tour features, often making both available as a suite
at a slightly reduced price.
Display Options
The two main methods of displaying panoramas, and indeed virtual tours, are Apple’s
QuickTime VR (QTVR) and its variations, or the use of a Java player. Both options
give very good results, QTVR being especially suited to displaying virtual reality (VR)
with a cubic projection. Developers have performed miracles with Java code, enabling
panoramic images to be displayed instantly in full-screen mode on practically any computer.
Some of the latest and most exciting developments involve the display of special
effects within a basic panoramic image, such as moving an object independently of the
pan. Another is the use of Adaptive Dynamic Range (ADR) to solve one of the key
panoramic problems: how to cope with the extreme exposure range encountered in
360 degrees with fields of view both towards and away from the light source. (See the
section “SPi-V,” later in this chapter).