After you have selected the images to be mosaicked, completed any color balancing, histogram matching, or image dodging, and checked overlapping images for possible cutline needs, you are ready to output the images to an actual mosaic file. When you select Set Mode for Output option, the first feature to use is Output Image Options. After choosing those options, you can preview the mosaic and then process it to disk.
Output Image Options
Define your output map areas and change output map projection if you wish. Select from using Union of All Inputs, User-defined AOI, Polygon Vector File, Map Series File, USGS Maps Database, or ASCII Sheet File as your defining feature for an output map area. The default is Union of All Inputs.
Different choices yield different options to further modify the output image. For instance, if you select User-defined AOI, then you can output multiple AOI objects to either multiple files or a single file. If you choose Map Series File, you can type a filename and choose whether to treat the map extent as pixel centers or pixel edges.
ASCII Sheet File Format
There are two file formats for ASCII sheet files. One lists the coordinates on separate lines with hard-coded identifiers: UL, UR, LL, LR. This format can contain multiple sheet files separated by the code -99. The sheet name is optional.
UL 0 0
LR 10 10
UL 0 0
UR 5 5
LL 3 3
LR 10 10
The second format lists the coordinates on a single line with a blank space as a separator. The sheet name is optional.
third_sheet_name 0 0 10 10(north-up orthoimage)
fourth_sheet_name 0 0 3 0 3 3 0 3(rotated orthoimage)
Image Boundaries Type
There are two types of image boundaries. If you enter two image coordinates the boundary is treated as a North-up orthoimage. If you enter four image coordinates, it is treated as a Rotated orthoimage.
You can select Clip Boundary, in which any area outside of the Clip Boundary is designated as background value in your output image. This differs from the User-defined AOI because Clip Boundary applies to all output images. You can also change the output map projection.
You can change the output cell size, and select the output raster data type.
When you finish selecting output image options, you can preview the mosaicked image before saving it as a file.
Run Mosaic To Disk
When you are ready to process the mosaicked image to disk, browse to the directory where you want to store your mosaicked image, and type the file name for the image. In Output Options tab, select from options such as Output to a Common Look Up Table, Ignore Input Values, Output Background Value, and Create Output in Batch mode. You can choose from any of these according to your desired outcome.