doc/libvips-mosaicing.md
Title: Operator index > By section > Mosaicing
<!-- libvips/mosaicing -->These functions are useful for joining many small images together to make one large image. They can cope with unstable contrast and arbitrary sub-image layout, but will not do any geometric correction. Geometric errors should be removed before using these functions.
The mosaicing functions can be grouped into layers:
The lowest level operation is [[email protected]] which joins two images together left-right or up-down with a smooth seam.
Next, [[email protected]] uses search functions plus the two low-level merge operations to join two images given just an approximate overlap as a start point.
[[email protected]] is a first-order analogue of the basic mosaic functions: it takes two approximate tie-points and uses them to rotate and scale the right-hand or bottom image before starting to join.
Finally, [[email protected]] can be used to remove contrast differences in a mosaic which has been assembled with these functions. It takes the mosaic apart, measures image contrast differences along the seams, finds a set of correction factors which will minimise these differences, and reassembles the mosaic. [[email protected]] uses the same techniques, but will reassemble the image from a different set of source images.