An imagery mosaic is a container that allows multiple imagery sources to be processed as one unit. A mosaic maintains its constituent images intact, without masking or feathering the edges where they meet. Only the external edges of the mosaic are masked and feathered.
If you have a collection of images whose edges perfectly abut each other, it's often a good idea to create a mosaic before adding the images to a layer. For example, imagery for a city might include a number of images. If you add those images directly to a layer, their edges are feathered, and some detail may be lost. However, if you add the images to a mosaic first, the edges of the individual images where they meet are maintained.
Mosaics are meant for contiguous images. Although technically, you can create a mosaic from non-contiguous images, there wouldn't be a reason to do so.
The images in a mosaic must match in the following ways:
- number of bands
- standard North/South orientation
To mosaic images, you should first tag the images, then do a search, and then add all the search results to a mosaic.
You'll need to fill in the following information.
|Name||The name of this mosaic.|
|Description||A text description for this mosaic. This description will be visible only within Google Maps Engine and not to external viewers of a map that includes this mosaic.|
|Tags||The text strings in response to which you want this mosaic to be found.|
|Sharing settings||The access list to which you want to grant permission to work with this mosaic.|
|Attribution||Acknowledgment for the source of the imagery.|
When the mosaic is processed, you can add it to a layer as you would any other image data source.
You can add images to a mosaic and remove images from a mosaic. When you make changes to a mosaic, you must reprocess the mosaic and reprocess any layer that contains the mosaic.