Using Map Viewer, you can modify the display of imagery in your web maps. As the author of a map, you decide how the imagery in the map is presented. You can modify the display settings for dynamic and tiled imagery layers.
When you add an imagery layer to a map, the map initially uses the default display settings of the imagery layer. To change the display settings, you can modify the properties, styles, and processing templates of imagery layers or adjust the image display order of each layer.
The styles for displaying imagery layers depend on the type of raster or imagery data contained in the layer and the source of the layer. Different styling options are called renderers. For example, the Stretch renderer uses the statistics and histograms of pixel values in a single raster band to enhance the display of continuous data. The Classify renderer allows you to group ranges of pixel values into classes and assign colors to the individual classes. See Style imagery in Map Viewer for details on displaying imagery with an appropriate style.
Set resampling type
Resampling options have been added to the Properties toolbar in Map Viewer, which allows you to change the Resampling type used to display the imagery layer. Depending on the imagery layer, modifying the Resampling type can improve visual interpretation of the imagery layer in the map.
- Confirm that you are signed in and, if you want to save your changes, that you have privileges to create, update, and delete content.
- In Map Viewer, open the map containing the layer or add the layer directly.
- On the Settings (light) toolbar, click the Properties button.
The Properties pane appears.
- In the Appearance section, locate the Resampling type drop-down button.
The default resampling type is Bilinear for most imagery layers.
- Choose one of the following Resampling type options from the drop-down menu:
- Nearest neighbor—Performs a nearest neighbor assignment and is the fastest of the interpolation methods. It is used primarily for discrete data, such as a land-use classification, since it will not change the values of the cells. The maximum spatial error will be one-half the cell size.
- Majority—Performs a majority algorithm and determines the new value of the cell based on the most popular values in the filter window. It is mainly used with discrete data just as the nearest neighbor method; the Majority option tends to provide a smoother result than Nearest neighbor. The Majority resampling method will find corresponding 4 by 4 cells in the input space that are closest to the center of the output cell and use the majority of the 4 by 4 neighbors.
- Bilinear—Performs a bilinear interpolation and determines the new value of a cell based on a weighted distance average of the four nearest input cell centers. It is useful for continuous data and will cause some smoothing of the data.
- Cubic—Performs a cubic convolution and determines the new value of a cell based on fitting a smooth curve through the 16 nearest input cell centers. It is appropriate for continuous data, although it may result in the output raster containing values outside the range of the input raster. If this is unacceptable, use Bilinear instead. The output from cubic convolution is geometrically less distorted than the raster achieved by running the nearest neighbor resampling algorithm. The disadvantage of the Cubic option is that it requires more processing time.
The display of the imagery layer will change based on the Resample type chosen.
Change the image display order
A dynamic imagery layer of a mosaic dataset contains a collection of images. These images are mosaicked on the fly and behave like a single image when you view the layer. For example, the USA NAIP Imagery: Natural Color imagery layer from ArcGIS Living Atlas is published from a mosaic dataset.
When working with these types of imagery layers in a web map, you can modify the image display order and determine how to resolve overlapping areas. Image order refers to how images are displayed when there are multiple images over the same area.
To change the image display order for a mosaic dataset imagery layer, complete the following steps:
- Confirm that you are signed in and, if you want to save your changes, that you have privileges to create, update, and delete content.
- In Map Viewer, open the map containing the layer or add the layer directly.
- On the Settings (light) toolbar, click Image display order
. - In the Image Display Order pane, specify the Mosaic method to use to prioritize imagery. The options are as follows:
- North West—The order is based on the center of each image's distance to the northwest corner of the mosaicked raster layer. Since this presents a static display, it is useful when you do not want the images to change percentage as you roam across the mosaic.
- By Attribute—Select an attribute to determine the image display order. The image with the highest priority according to its attribute will be displayed on top. For example, to show the most recent images, you can display the images based on their acquisition dates. Another common attribute to use is the percentage of cloud cover to get the clearest image possible.
- Closest to Center—The images with their image centers closest in distance to the center of the screen display on top. This is useful if you are interested in viewing features from a more persistent point of view.
- Closest to Nadir—The images with their image centers closest to a nadir (vertical) view angle display on top. This is useful if you are interested in viewing imagery with a minimum of building and feature lean.
- Seamlines—Images are prioritized based on the existing seamlines. If you choose this option, use Blend to resolve any overlapping pixels.
- Lock Raster—Locked images will be displayed.
- None—The order is based on the ObjectId value.
- Specify the Mosaic operator for resolving overlapping pixels.
The options are as follows:
- First—Display the pixel value from the image that has the highest priority as set by the mosaic method.
- Last—Display the pixel value from the image that has the lowest priority as set by the mosaic method.
- Minimum—Display the lowest pixel value.
- Maximum—Display the highest pixel value.
- Average—Display the mean pixel value.
- Blend—Use the blend option for overlapping areas to create a smooth transition along seamlines.
- Sum—Add all of the pixel values together.
- Optionally, reverse the order of priority by turning on the Reverse the order toggle button.
- Click Done to close the Image Display Order pane.