Repairing a mosaic from overlapping images

A task performed commonly is to repair one or more areas of a mosaic. For example, clouds and road overpasses are often areas of difficulty.

When mosaicking, an overlapping image that has a corresponding difficulty-free area can often be used in a repair. By considering a set of overlapping images, you can select pixels from an image that may resolve the difficulty. Those pixels will be copied and can be pasted as a new mosaic map layer.

Note: It may take several Mosaic GeoFill tasks to fully repair the AOI. For example, in the bridge repair, shown herein, only the first of several Mosaic GeoFill tasks is described as a demonstration of the technique. Additional repairs to the overpass; that is, outside the polygon, must be completed as subsequent tasks.

To repair a mosaic from overlapping imagery

Zoom, pan, or both, as necessary to the AOI you want to repair, and then access the Mosaic GeoFill toolbar.
On the toolbar, click Mosaic GeoFill, and then in the viewer, draw a polygon around the area you want.
Notice that after you close the polygon, the polygon is filled with the pixels from the first overlapping image. On the toolbar, you can click Previous and Next to cycle through the available overlapping images, and the interior of the polygon displays the overlapping area of each. If necessary, you can refine the selection of images you want to use in the Mosaic File Set window. For more information about working with the images in your file set, see Working with a mosaic file set.
Click Previous or Next, as applicable, to cycle through the available overlapping images to find an image that will suit the repair.
Tip: You can also press Ctrl+F for Next or Ctrl+D for Previous. To exclude an unsuitable image, press Ctrl+E.
To achieve a smoother blend around the outside of the copied pixels, you can specify a Blend width in the Settings.
You can also set the blend width before you draw the polygon or anytime the polygon is active.
On the toolbar, click Show Selection Edge (to hide the selection edge), and then verify the suitability of the blend between the inside and outside of the polygon.
You can further adjust the blend width to suit.
After you are satisfied with the repair, including the blend width, on the toolbar, click Paste.

In the preceding figure, image 1 shows the overpass to be repaired. Image 2 shows the first overlapping image, which, while could be used, is deemed unsuitable, because the roadways do not align well enough. Image 3 shows the second overlapping image, which is also unsuitable due to residue of the bridge edge and vehicular traffic. Image 4 is deemed suitable, because the bridge repair is adequate and the roadways align well.