You can alter certain settings on a hosted dynamic imagery layer. The following sections describe how the layer owner, or an administrator, can manage the settings for a hosted imagery layer and the data it contains.
Note:
For ArcGIS Enterprise, imagery layers created through ArcGIS Image Server will be dynamic imagery layers and be referenced in Content section as an Imagery layer.
Manage item details
As the owner of a hosted imagery layer, or an administrator, you can change the name, thumbnail, summary, description, terms of use, sharing settings, folder, tags, and credits of hosted imagery layer items. An administrator can change the owner of a hosted imagery layer.
- Sign in to your organization and open the item details page for the hosted imagery layer.
- On the Overview tab, click the Edit button next to the property you want to change.
- Change the property and click Save.
Manage general settings
As the owner of a hosted imagery layer, or an administrator, you can modify the content status, delete protection setting, and extent of the layer.
- Sign in to your organization and open the item details page for the hosted imagery layer.
- On the Settings tab, select Mark as Authoritative or Mark as Deprecated.
- Optionally, check the box to prevent the item from being accidentally deleted.
- To set an extent to make the layer searchable by location, click Edit Extent.
- When finished, click Save.
Manage dynamic imagery layer settings
Hosted dynamic imagery layers have additional settings such as default resampling, compression, mosaic methods, and mensuration that can be modified by an administrator or owner of the dynamic imagery layer.
Modify image request options
You can modify the limitations on the size of the imagery that is queried or displayed when rendering an imagery layer. For example, increase the size of the request to display a larger area of imagery. Follow these steps to modify the portions of the imagery layer that can be queried and displayed in the map:
- Sign in to your organization and open the item details page for the hosted dynamic imagery layer.
- Click the Settings tab.
- Scroll to the Imagery Layer (hosted) section.
- Optionally, modify one of the following settings:
- Maximum columns per request—The maximum number of columns that the server allows in a client request.
If the client’s request exceeds this value, none of the pixels will be returned.
Note:
The request size limit for the dynamic image service is set to 4,000 x 4,000 pixels, or smaller. You can choose to adjust the size of the Maximum columns per request, but this parameter setting will revert to 4,000 pixels if you specified larger than 4,000 columns.
- Maximum rows per request—The maximum number of rows that the server allows in a client request.
If the client’s request exceeds this value, none of the pixels will be returned.
Note:
The request size limit for the dynamic image service is set to 4,000 x 4,000 pixels, or smaller. You can choose to adjust the size of the Maximum columns per rows, but this parameter will revert to 4,000 pixels if you specified larger than 4,000 rows.
- Maximum samples count—This generates sample point locations, pixel values, and corresponding spatial resolutions of the source data for a given geometry. By default, the maximum number of sample locations is 1,000.
- Maximum columns per request—The maximum number of columns that the server allows in a client request.
If the client’s request exceeds this value, none of the pixels will be returned.
- When finished, click Save.
Set the default resampling method
The default resampling method determines how pixels are displayed when the imagery layer is added to a map. For example, you can change the resampling method from Bilinear Interpolation to Nearest Neighbor if most of the imagery in the collection is categorical. Follow these steps to change the default resampling method for imagery display:
- Sign in to your organization and open the item details page for the hosted dynamic imagery layer.
- Click the Settings tab.
- Scroll to the Imagery Layer (hosted) section and select one of the following options for the Default resampling method setting:
- Nearest Neighbor—Recommended for discrete data
- Bilinear Interpolation—Recommended for continuous data
- Cubic Convolution—Recommended for continuous data
- Majority—Recommended for discrete data
- When finished, click Save.
Choose the compression options
Compressing your raster data improves performance over a network. Follow these steps to specify the allowed compression types:
- Sign in to your organization and open the item details page for the hosted dynamic imagery layer.
- Click the Settings tab.
- Scroll to the Imagery Layer (hosted) section and check the check boxes to allow one or more of the following options for the Allowed compressions setting:
- None—No compression will occur.
- JPEG—Lossy compression that uses the public JPEG compression algorithm. If you choose JPEG, you can also specify the Default JPEG compression quality setting. The valid compression quality value ranges are from 0 to 100, with 75 being the default. This compression can be used for JPEG files, TIFF files, and geodatabases.
- LZ77—Lossless compression that preserves all raster cell values.
- LERC—Lossless or lossy compression that divides the raster into a number of pixel blocks—in which each pixel can be quantized and bit stuffed—based on a number of block statistics, including the maximum error allowable.
- When finished, click Save.
Change the raster function template
Dynamic imagery layers can be rendered using raster function templates, which process pixel values on the fly to generate a display showing the results.
To allow raster functions and specify the raster function templates that can be used for rendering, follow the steps below:
- Sign in to your organization and open the item details page for the hosted dynamic imagery layer.
- Click the Settings tab.
- Scroll to the Imagery Layer (hosted) section and check the Allow function check box to allow users to access the raster function templates associated with the layer.
- Click the Choose Raster Function Template button to launch the raster function template browser.
- Browse to the raster function template to add as rendering options for the dynamic imagery layer, and click the Select button.
- If you choose more than one raster function template, you can set one as the default template.
- When finished, click Save.
Specify mosaic options
When the imagery layer was generated from a mosaic dataset or a collection of images, you can modify the mosaic or catalog properties of the imagery layer. These parameters control or limit the access users have to metadata and the catalog fields, as well as limit the requests for records from the mosaic dataset tables. These parameters can affect the load on the server. The more you allow a user to view and query, the greater the draw on the server.
To modify the mosaic or catalog properties of the dynamic imagery layer, use the following steps:
- Sign in to your organization and open the item details page for the hosted dynamic imagery layer.
- Click the Settings tab.
- Scroll to the Imagery Layer (hosted) section and check the Catalog check box.
- Optionally, modify one or more of the following settings:
Maximum number of rasters per mosaic
The maximum number of rasters that can be mosaicked per request. This prevents the server from needing to open and perform processing on large numbers of rasters for a single request.
If the client's request requires more than this number of rasters to be accessed, only this number of rasters are accessed. None of the pixels for the additional rasters are returned, potentially causing gaps in the resulting image. It is recommended that overviews be built so that the client does not end up with gaps in the display.
Maximum number of records returned per request
The maximum limit of the number of records transmitted per transaction. If a user’s request exceeds this value, the image returned uses the maximum allowed rasters.
Allowed fields
The fields in the attribute table that are transmitted to the client. Uncheck the fields that you don't want a client to view or use in a query.
Allowed mosaic methods
The allowable mosaic methods for the image service. The possible mosaic methods are as follows:
- Closest To Center
- North-West
- Lock Raster
- By Attribute
- Closest To Nadir
- Closest To Viewpoint
- Seamline
- None
If you choose By Attribute, you can specify the Mosaic method sort field setting and the base Sort value setting.
- When finished, click Save.
Allow mensuration types
To allow image mensuration on the imagery layer, including tools to measure point, distance, area, and feature height from an image, use the following steps:
- Sign in to your organization and open the item details page for the hosted dynamic imagery layer.
- Click the Settings tab.
- Scroll to the Imagery Layer (hosted) section and check the Mensuration check box to allow users to perform measurements in the imagery layer.
- Check the check boxes to allow one or more of the following mensuration options:
- None—No mensuration can be performed.
- Basic—The basic mensuration operations can be performed: point, distance, area, and centroid.
- Base-Top Height—Height measurement can be performed from the base of an object to the top of the object. Measurements are assumed to be perpendicular to the base; therefore, the line being measured along the building must have its endpoint directly above the start point. Measurements will not be as accurate for objects that taper or lean from the base.
- Base-Top Shadow Height—Height measurement can be performed from the base of the object to the top of the object's shadow on the ground. The point in the shadow must represent a point on the visible object that is perpendicular to the base.
- Top-Top Shadow Height—Height measurement can be performed from the top of the object to the top of the objects's shadow on the ground. The measurement points on the object and its shadow must represent the same point. This tool is useful for obtaining the height of an object on the top of a structure, for example, if there is a smaller room than the dimensions of the building or a tower on the top. You can identify the top point of this feature in the image and identify the same point in the shadow.
- 3D—The 3D mensuration operations can be performed: 3D point, 3D distance, 3D area, 3D centroid, and volume.
- When finished, click Save.
Manage images in an image collection
You can publish a collection of images as a hosted dynamic imagery layer in your organization. After publishing, the owner of the layer or the administrator can build image footprints and overviews, calculate statistics, and define NoData pixel values.
Build footprints
Footprints contain the outline of each raster or image within the image collection. This outline is not always the extent of each raster dataset but can be the extent of the valid raster data within the dataset. To build footprints for a hosted imagery layer published with an image collection, use the following steps:
- Sign in to your organization and open the item details page for the image collection imagery layer.
- Click the Image Management tab, and click the Build Footprints button.
- Optionally, modify one or more of the following settings:
Method
The footprint computation method:
- Radiometry—Exclude pixels with a value outside of a defined range. This option is generally used to exclude border areas, which do not contain valid data. If you choose this option, you can also specify the minimum and maximum values. This is the default.
- Geometry—Restore the footprint to its original geometry.
Approximate number of vertices
The complexity of the footprints is defined by the number of vertices. Valid values range from 4 to 10,000, or you can set the value to -1 for no generalization. A higher number of vertices will result in more accurate, and likely more irregular, footprints.
Shrink distance
Clip the footprint by this distance. This can eliminate artifacts from using lossy compression, which causes the edges of the image to overlap into NoData pixels.
Simplification method
Reduce the number of vertices in the footprint to improve performance.
- None—Do not limit the number of vertices. This is the default.
- Convex hull—Use the minimum bounding box to simplify the footprint.
- Envelope—Use the envelope of each mosaic dataset item to simplify the footprint.
Skip overviews
Adjust the footprints of overviews.
- Checked—Do not adjust the footprints of overviews. This is the default.
- Unchecked—Adjust the footprints of overviews and associated raster datasets.
Update boundary
Update the boundary of the mosaic dataset if you have added or removed imagery that changes the extent.
- Checked—Update the boundary. This is the default.
- Unchecked—Do not update the boundary.
Maintain sheet edges
Alter the footprints of raster datasets that have been tiled and are adjacent (line up along the seams with little to no overlap).
- Unchecked—Remove the sheet edges from all the footprints. This is the default.
- Checked—Maintain the footprints in their original state.
Request size
Set the resampled extent (in columns and rows) for the raster when building footprints. Greater image resolution provides more detail in the raster dataset but increases the processing time. A value of -1 will compute the footprint at the original resolution.
Minimum region size (pixels)
Avoid small holes in your imagery when using pixel values to create a mask. For example, your imagery may have a range of values from 0 to 255, and to mask clouds, you've excluded values from 245 to 255, which may cause other, noncloud pixels to be masked as well. If those areas are smaller than the number of pixels specified here, they will not be masked out.
Minimum thinness ratio
Define the thinness of slivers on a scale from 0 to 1.0, where 1.0 represents a circle and 0.0 represents a polygon that approaches a straight line.
Polygons that are below both the Maximum Sliver Size and Minimum Thinness Ratio values will be removed from the footprint.
Maximum sliver size
Identify all polygons that are smaller than the square of this value. The value is specified in pixels and is based on the Request Size value, not the spatial resolution of the source raster.
Polygons that are below both the Maximum Sliver Size and Minimum Thinness Ratio values will be removed from the footprint.
- When finished, click Run.
The footprints are built for the images in the image collection layer, and you return to the Image Management tab.
Build overviews
Overviews are lower-resolution images created to increase display speed and reduce CPU usage when viewing the image collection at a larger (zoomed-out) scale. To build overviews for a hosted imagery layer published with an image collection, use the following steps:
- Sign in to your organization and open the item details page for the image collection imagery layer.
- Click the Image Management tab, and click the Build Overviews button.
- Click Run.
The overviews are built for the images in the image collection layer, and you return to the Image Management tab.
Compute Seamlines
Seamlines are used to smooth the blending of overlapping images in an image collection. Computing the seamlines allows you to control the display of images in an image collection to improve the display according to the computation.
- Sign in to your organization and open the item details page for the image collection imagery layer.
- Click the Image Management tab, and click the Compute Seamlines button.
- Choose the Seamline computation method from the drop-down menu, which includes:
Radiometry
Generate seamlines based on the spectral patterns of features within the imagery.
Geometry
Generate seamlines with overlapping areas based on the intersection of image footprints.
Edge detection
Generate seamlines over intersecting areas based on the edges of features in the overlap area.
Disparity
Determine seamlines by leveraging the disparity between images of the stereo pairs and is useful for large-scale mosaicking where the mosaic area contains buildings.
Voronoi
Partition image footprints based on an area Voronoi diagram.
- Optionally, enter a value for the Seamline blend width.
- Optionally, expand the Settings and modify one or more of the following settings:
Minimum region size
Any seamline polygons smaller than this specified threshold will be removed in the seamline result.
Blend type
Blending (feathering) occurs along a seamline between pixels of overlapping images. The blend width defines how many pixels will be blended relative to the seamline.
Minimum thinness ratio
Define how thin a polygon can be before it is considered a sliver. This is based on a scale from 0 to 1.0, where a value of 0.0 represents a polygon that is almost a straight line, and a value of 1.0 represents a polygon that is a circle.
Maximum sliver size
Specify the maximum polygon size to be considered a sliver. This parameter is specified in number of pixels and is based on the Request size, not the spatial resolution of the source raster. Any polygon that is less than the square of this value [(max_sliver_size)2] is considered a sliver. Slivers are removed when building seamlines.
- Click Run.
The seamlines are computed for the images in the image collection layer, and you return to the Image Management tab.
Compute Color Corrections
Balances the colors in an imagery layer so that the tiles appear seamless.
- Sign in to your organization and open the item details page for the image collection imagery layer.
- Click the Image Management tab, and click the Compute Color Corrections button.
- Choose the Color balance method from the drop-down menu, which includes:
Dodging
Change each pixel's value toward a target color. With this technique, you must also choose the type of target color surface, which affects the target color. Dodging tends to give the best result in most cases.
Histogram
Change each pixel's value according to its relationship with the histogram of a reference image. The reference histogram can be derived from all of the images. This technique works well when all of the images have a similar histogram.
Standard deviation
Change each of the pixel's values according to its relationship with the histogram of the target raster, within one standard deviation. The standard deviation can be calculated from all of the rasters. This technique works best when all of the rasters have normal distributions.
- Optionally, choose the Color balancing (dodging) surface type drop-down menu, which includes:
Single color
Use when there are only a small number of images and a few different types of ground features. If there are too many images or too many types of ground surfaces, the output color may become blurred. All the pixels are altered toward a single color point-the average of all pixels.
Color grid
Use when you have a large number of images, or images contain a large number of diverse ground objects. Pixels are altered toward multiple target colors, which are distributed across the image collection.
First order
This technique tends to create a smoother color change and uses less storage in the auxiliary table, but it may take longer to process compared to the color grid surface. All pixels are altered toward many target colors obtained from the two-dimensional polynomial slanted plane.
Second order
This technique tends to create a smoother color change and uses less storage in the auxiliary table, but it may take longer to process compared to the color grid surface. All input pixels are altered toward a set of multiple target colors obtained from the two-dimensional polynomial parabolic surface.
Third order
This technique tends to create a smoother color change and uses less storage in the auxiliary table, but it may take longer to process compared to the color grid surface. All input pixels are altered toward multiple target colors obtained from the cubic surface.
- Optionally, expand the Settings and if you choose to Recalculate statistics for the imagery layer, then you can modify one or more of the following settings:
Number of rows to skip
Specifies the number of rows to skip when recalculating the statistics.
Number of columns to skip
Specifies the number of columns to skip when recalculating the statistics.
- Click Run.
The color corrections are applied to the image collection layer, and you return to the Image Management tab.
Calculate statistics
Statistics are required for your imagery to perform certain tasks, such as applying a contrast stretch or classifying your data. Calculating statistics allows a better display. To calculate statistics for the images published as an image collection, use the following steps:
- Sign in to your organization and open the item details page for the image collection imagery layer.
- Click the Image Management tab, and click the Calculate Statistics button.
- Optionally, modify one of the following settings:
Number of rows to skip
The number of vertical pixels between pixel samples. This value controls the portion of each image that is used when calculating the statistics. A value of 1 will use every pixel in each column, and a value of 10 will use every tenth pixel.
Number of columns to skip
The number of horizontal pixels between pixel samples. This value controls the portion of each image that is used when calculating the statistics. A value of 1 will use every pixel in each row, and a value of 10 will use every tenth pixel.
Ignore values
The pixel values that are not to be included in the statistics calculation.
- Click Run.
The statistics will be calculated for the images in the image collection layer, and you return to the Image Management tab.
Define NoData pixel values
You can specify one or more values to be represented as NoData in the image collection. NoData values can be used to define pixel values that surround an image, or to set transparent values. To set NoData values for the images published as an image collection, use the following steps:
- Sign in to your organization and open the item details page for the image collection imagery layer.
- Click the Image Management tab, and click the Define NoData Pixel Values button.
- Enter an integer pixel value in the NoData pixel value parameter. Alternatively, check the Define value pixel value range check box to specify a minimum and maximum valid pixel value. Any pixel value that falls outside the valid range will be set as NoData.
- Optionally, check A pixel represents a void only when the NoData criteria is met for all bands. This applies to multiband imagery only.
- Unchecked—If any band has a pixel with NoData, the pixel is classified as NoData for the multiband imagery layer. This is the default.
- Checked—The pixel must be classified as NoData in all bands in order to be classified as NoData for the multiband imagery layer.
- Click Run.
The NoData pixels are defined for the images in the image collection layer, and you return to the Image Management tab.