An attribute table is created when you create a mosaic dataset; some fields always appear by default. When you add data using a particular raster type, you can add more fields to contain specific metadata information. You can also add and populate more fields. These fields can be used when defining a query on the mosaic dataset, an imagery layer in a dynamic image collection, or an image service using the mosaic dataset. If you don't want all the fields exposed to those using the mosaic dataset, you can edit Allowed Fields on the Mosaic Dataset Properties dialog box.
The attribute table contains the following default fields:
- ObjectID—The ObjectID field is maintained by ArcGIS and provides a unique ID for each row in a table. It can be used as an image ID when using the Lock Raster mosaic method.
- Raster—The Raster field is automatically populated when an image is added to a mosaic dataset and indicates the type of data in the mosaic dataset, usually reported as a Raster.
- Name—The name of the source defined by the raster type, which can be the name of the raster dataset file or the metadata file defined in the raster type.
- MinPS and MaxPS—The minimum and maximum pixel sizes are computed from the LowPS and HighPS values and depend on the overlapping raster datasets. These values control which raster is used to create the dynamically mosaicked image at particular scales or resolutions of the display or image request. For example, if you create a mosaic dataset from 1-meter source rasters and build overviews, you see a range of minimum and maximum pixel sizes. If you view the entire mosaic dataset (fully zoomed out), you likely are viewing the image with the largest MinPS and MaxPS values. As you zoom in, the resolution of the image increases and smaller pixel sizes are required.
- LowPS and HighPS—These values are extracted from the source rasters and used to define the range of pixel sizes that
the raster dataset contains. For example, a raster dataset that
contains a pyramid (or internal overview) has a range of
pixel sizes—the low value represents the base pixel value, and the high value represents the top overview that is being used. For raster datasets with no pyramids, the low and high
pixel sizes may be the same value.
The LowPS and HighPS fields are used to control the display order or to display a lower-resolution raster with a specified footprint to cover areas that should not be seen at high resolutions. The values in the field will control the order as the mosaic dataset is used in the map through different map scale levels and spatial resolutions.
A null value is presumed equal to zero.
- Category—Used for quickly identifying the type of dataset and its status in the mosaic dataset:
- 1—Primary (base) data
- 3—Unprocessed overview
- 4—Partially processed overview
- 254—Incomplete and needs to be synchronized
- 255—Custom item
- Tag—Used for identifying the raster dataset that will participate in functions defined in a function template. For example, importing one mosaic dataset to another using the Table raster type (with some function templates defined on the raster type) depends on the Tag field. In most cases, the value is defined by the raster type used for creating the dataset entry in the table.
- GroupName—The name of one or more rows in the table that belong together. For example, for a Landsat scene, the panchromatic and multispectral rasters are added as separate items in the table. Since each is required to participate in pan sharpening when they're added using a particular raster type, they are assigned a group name. This is defined by the raster type that created the dataset entry in the table.
- ProductName—This is derived from either the name or product type defined in the raster type.
- CenterX and CenterY—The x- and y-coordinates identifying the centroid or nadir of the raster dataset. They are used to render a mosaicked image when the mosaic method is Closest To Nadir or Closest To Viewpoint.
- ZOrder—Controls the ordering used in determining how the rasters are mosaicked together when using the Closest To Center, North-West, By Attribute, Closest To Nadir, or Closest To Viewpoint mosaic methods. Generally, lower values push forward and higher values push backward. For example, if there are three values, 10, 0, and -10, the higher value (10) becomes heavier and has a lower priority when creating the mosaicked image, so it may be covered up by a lower ZOrder value (0 or -10). The lower the value, the more important and lighter it becomes, so it's displayed on top of a higher ZOrder value (-10 is on top of 0). Another way to think about this order of display value is the higher number is displayed first and the remaining rasters are displayed over the preceding raster in descending order, so the lowest numbered raster is on top.