An image service can be displayed and rendered in many ways based on the type of metadata it contains and how the service was prepared. Based on the quality of the image and your workflow task, you may want to improve the appearance of your imagery. The display tools allow you to apply common display settings to your imagery and change the order of your imagery to gain the most value out of each pixel.
Image Display tool
The Image Display tool allows you to use renderers, change band combinations, and apply common settings such as dynamic range adjustment (DRA) and gamma to your imagery.
Apply a renderer
Image services can be displayed, or rendered, in many ways. Rendering is the process of displaying your data. Some image services have predefined templates associated with them. If an image service contains predefined renderers, they are available in the renderer drop-down menu with the top-most renderer selected as the default. If the image service does not contain a predefined renderer, the renderer drop-down menu is set to User Defined Renderer.
To change the image service renderer, complete the following steps:
- Click the overflow menu in the upper right corner of the imagery exploitation canvas.
- In the Display Tools list, click Image Display.
- In the Renderer drop-down list, choose a renderer.
- Predefined renderer—Any renderer in the list other than User Defined Renderer. When you choose a predefined renderer, no additional user-defined settings can be set.
- User defined renderer—Available for all image services. When you choose a user-defined renderer, you can apply user-defined settings such as DRA and gamma.
Once you choose a renderer, it is automatically applied to the image service.
Apply DRA settings
Dynamic range adjustment enhances the image by dynamically stretching the image based only on the pixel values in the display, not all pixels in the service.
To apply DRA, complete the following steps:
- Click the overflow menu in the upper right corner of the imagery exploitation canvas.
- In the Display Tools list, click Image Display.
- In the Renderer drop-down list, choose User Defined Renderer.
- Click DRA. You will notice a change in the pixels of your image in the current view.
Note:
DRA requires a stretch type to be applied. When DRA is toggled on, a minimum and maximum stretch type is automatically applied to the imagery service. This stretch type can be changed using the Enhancements tool.
Apply gamma settings
Gamma enhances an image by dynamically stretching the middle values in an image while keeping the extreme high and low values constant.
To apply gamma, complete the following steps:
- Click the overflow menu in the upper right corner of the imagery exploitation canvas.
- In the Display Tools list, click Image Display.
- In the Renderer drop-down list, choose User Defined Renderer.
- Click Gamma. You will notice a change in the pixels of your image in the current view.
Apply band combinations
The band combination setting allows you to specify which bands are displayed using the red, green, and blue color composite scheme. Using different color combinations, you can display your imagery with various color effects. You can use natural color (red, green, and blue), which displays the layer as you would normally see it. Other color combinations can highlight vegetation, urban areas, water, and other features.
The band combination setting is only available when User Defined Renderer is chosen and the image service is a multiband service.
To change the multispectral band combinations that display, complete the following steps:
- Click the overflow menu in the upper right corner of the imagery exploitation canvas.
- In the Display Tools list, click Image Display.
- In the Renderer drop-down list, choose User Defined Renderer.
- For RGB Composite, click the band selection drop-down
arrow and choose band numbers for red,
green, and blue.
Note:
If the image service is a single-band service, the message Not available on single-band services appears.
- Click the Apply Bands button to apply the RGB composite.
- Optionally click the Reset Bands button to return to the default combination.
Enhancements tool
The Enhancements tool helps improve the quality of the image. The stretch enhancement changes an image's brightness, contrast, and gamma through stretch types. The convolution enhancement help filter the pixels in the image so it can be used to sharpen, blur, or detect edges within an image.
Stretch
To apply stretch enhancement to your images, complete the following steps:
- Click the overflow menu in the upper right corner of the imagery exploitation canvas.
- In the Display Tools list, click Enhancements.
- Under Choose Enhancement Type, click Stretch.
- Under Available Types, choose from the list of options.
- After choosing the enhancement type, you can click Apply DRA or Apply Gamma.
Note:
If DRA or Gamma is enabled in the Image Display tool, DRA and Gamma will automatically be enabled in the Enhancement tool and set to minimum maximum stretch type. Any change to the stretch type will be applied to the image when DRA is enabled. - To clear any stretch enhancements applied, click the Clear Enhancement button.
Convolution
To apply convolution enhancement to your images, complete the following steps:
- Click the overflow menu in the upper right corner of the imagery exploitation canvas.
- In the Display Tools list, click Enhancements.
- Under Choose Enhancement Type, click Convolution.
- From the Sharpen and Blur drop down, choose the sharpen or blur option you want applied to your images.
- From the Smoothen drop down, choose the smooth option you want applied to your images.
- From the Edge Detection drop down, choose the detection option you want applied to your images.
- To clear any convolution enhancements, click Clear Enhancement.
Reset enhancements
To reset the enhancements applied to your imagery, click the Reset Form button.
Display order tool
Image services contain one or more images that are mosaicked on-the-fly and behave like a single image when you browse the service. The display order tool can help determine the image order and how to resolve overlapping areas. This specifically becomes useful when there are multiple images over the same area. To specify a display order:
- Click the overflow menu in the upper right corner of the imagery exploitation canvas.
- In the Display Tools list, click Display Order.
- Utilize the available options to specify a priority ordering method and resolution to overlapping areas.
Note:
Each of the available options will depend on the properties set on the imagery layer.