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- Make a new directory for each painting, and keep all of the image files
for that painting (including a grey card and a grid) in that directory.
- VIPS can join up images in any layout, but you will get much less confused
when you assemble your images if you stick to a regular grid. This can be
difficult -- a good compromise is to keep one axis fixed and grab in rows
(or columns).
- You can help to reduce mosaicing errors later if you keep your rows (or
columns) as short as possible. So if the painting is in landscape format, grab
in columns (or turn the painting on its side and grab in rows); if the
painting is portrait, grab in rows (or turn the painting on its side and grab
in columns).
- The semi-automatic mosaic functions (see §3.3) need a minimum
overlap between the sub-images they join of around 20 pixels. For safety, you
should aim for a larger overlap than this: we recommend an overlap
of 60 pixels (around 20mm, usually).
- If the overlap area is featureless, it is worth identifying a good tie-point
and ensuring it is visible in both images, even if this means increasing the
overlap for one of the joins.
Next: 3.2.3 Correcting illumination
Up: 3.2.2 Capturing the data
Previous: 3.2.2.3 Image capture
Contents
John Cupitt
2004-12-20