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Image Presets enable AEM Assets to dynamically deliver images at different sizes, in different formats, or with other image properties there are generated dynamically. Each Image Preset represents a predefined collection of sizing and formatting commands for displaying images. When you create an Image Preset, you choose a size for image delivery. You also choose formatting commands so that the appearance of the image is optimized when the image is delivered for viewing.
Administrators can create presets for exporting assets. Users can choose a preset when they export images, which also reformats images to the specifications that the administrator specifies.
You can also create image presets that are responsive. If you apply a responsive image preset to your assets, they change depending on the device or screensize they are viewed on. You can configure image presets to use CMYK in the color space in addition to RGB or Gray.
This section describes how to create, modify, and generally manage image presets. You can apply an image preset to an image anytime you preview it. See Applying Image Presets.
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Smart imaging works with your existing image presets and uses intelligence at the last millisecond of delivery to further reduce image file size based on browser or network connection speed. See Smart Imaging for more information.
Like a macro, an Image Preset is a predefined collection of sizing and formatting commands saved under a name. To understand how Image Presets work, suppose your web site requires each product image to appear in different sizes, different formats, and compression rates for desktop and mobile delivery.
You could create two image presets: one with 500 x 500 pixels for desktop version and 150 x 150 pixels for the mobile version. You create two Image Presets, one called Enlarge to display images at 500x500 pixels and one called Thumbnail to display images at 150 x 150 pixels. To deliver images at the Enlarge and Thumbnail size, AEM looks up the definition of the Enlarge Image Preset and Thumbnail Image Preset. Then AEM dynamically generates an image at the size and formatting specifications of each Image Preset.
Images that are reduced in size when they are delivered dynamically can lose sharpness and detail. For this reason, each Image Preset contains formatting controls for optimizing an image when it is delivered at a particular size. These controls make sure that your images are sharp and clear when they are delivered to your web site or application.
Administrators can create Image Presets. To create an image preset, you can start from scratch or you can start from an existing one and save it under a new name.
You manage your image presets in AEM by tapping or clicking the AEM logo to access the global navigation console and then tapping or clicking the Tools icon and navigating to Assets > Image Presets.
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Any image presets you create are also available as dynamic renditions when you preview assets. To deliver or preview image presets, they must be published first unless you have Feature Pack 14410 installed.
Users that have Feature Pack 14410 do not need to publish image presets as image presets are automatically published. If you have this feature pack installed, you do not see a Publish or Unpublish option.
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By default, the system shows 15 renditions when you select Renditions in an asset's detail view. You can increase this limit. See Increasing the number of image presets that display.
If you intend to support the ingestion of AI, EPS, and PDF files so that you can generate dynamic renditions of these file formats, you may want to review the following information before you create image presets.
Adobe Illustrator's file format is a variant of PDF. The main differences, in the context of AEM Assets, is the following:
- Adobe Illustrator documents consist of a single page with multiple layers. Each layer is extracted as a PNG sub-asset under the main Illustrator asset.
- PDF documents consist of one or more pages. Each page is extracted as a single page PDF sub-asset under the main multi-page PDF document.
The sub-assets are created by the Create Sub Asset process component within the overall DAM Update Asset workflow. To see this process component within the workflow, tap Tools > Workflow > Models > DAM Update Asset > Edit.
See also Viewing pages of a multi-page file.
You can view the sub-assets or the pages when you open the asset, tap the Content menu, and select Subassets or Pages. The sub-assets are real assets. That is, PDF pages are extracted by the Create Sub Asset workflow component. They are then stored as page1.pdf, page2.pdf, and so on below the main asset. After they are stored, the DAM Update Asset workflow processes them.
To use Dynamic Media to preview and generate dynamic renditions for AI, EPS or PDF files, the following processing steps are required:
- In the DAM Update Asset workflow, the Rasterize PDF/AI Image Preview Rendition process component rasterizes the first page of the original asset--using the configured resolution--into a cqdam.preview.png rendition.
- The cqdam.preview.png rendition is then optimized into a PTIFF by the Dynamic Media Process Image Assets process component within the workflow.
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In the DAM Update Asset workflow, the EPS thumbnails step generates thumbnails for EPS files.
| Metadata property | Description |
| dam:Physicalwidthininches | Document width in inches. |
| dam:Physicalheightininches | Document height in inches. |
You access Rasterize PDF/AI Image Preview Rendition process component options by way of the DAM Update Asset workflow.
Tap on Adobe Experience Manager in the upper left, navigate to Tools > Workflow > Models. On the Workflow Models page, select DAM Update Asset, then on the toolbar tap Edit. On the DAM Update Asset workflow page, double-tap the Rasterize PDF/AI Image Preview Rendition process component to open its Step Properties dialog box.
| Process Argument | Default setting | Description |
| Mime Types | application/pdf application/postscript application/illustrator |
List of document mime-types that are considered to be PDF or Illustrator documents. |
| Max Width | 2048 | Maximum width of the generated preview rendition, in pixels. |
| Max Height | 2048 | Maximum height of the generated preview rendition, in pixels. |
| Resolution | 72 | Resolution to rasterize the first page, in ppi (pixels per inch). |
Using the default process arguments, the first page of a PDF/AI document is rasterized at 72 ppi and the generated preview image is sized at 2048 x 2048 pixels. For a typical deployment, you may want to increase the resolution to a minimum of 150 ppi or more. For example, a US letter size document at 300 ppi requires a maximum width and height of 2550 x 3300 pixels, respectively.
Max Width and Max Height limit the resolution at which to rasterize. For example, if the maximums are unchanged, and Resolution is set to 300 ppi, a US Letter document is rasterized at 186 ppi. That is, the document is 1581 x 2046 pixels.
The Rasterize PDF/AI Image Preview Rendition process component has a maximum defined to ensure that it does not create overly large images in memory. Such large images can overflow the memory provided to the JVM (Java Virtual Machine). Care must be taken to provide the JVM with enough memory to manage the configured number of parallel workflows, with each having the potential to create an image at the maximum configured size.
If you intend to support the ingestion of INDD files so that you can generate dynamic rendition of this file format, you may want to review the following information before you create image presets.
For InDesign files, sub assets are extracted only if the Adobe InDesign server is integrated with AEM. Referenced assets are linked based on their metadata. InDesign Server is not required for linking. However, the referenced assets must be present within AEM before the InDesign files are processed for the links to be created between the InDesign files and the referenced assets.
See Integrating AEM Assets with InDesign Server.
The Media Extraction process component in the DAM Update Asset workflow runs several preconfigured Extend Scripts to process InDesign files.
| Extend Script name | Default | Description |
| ThumbnailExport.jsx | Yes | Generates a 300 ppi thumbnail.jpg rendition that is optimized and turned into a PTIFF rendition by Dynamic Media Process Image Assets process component. |
| JPEGPagesExport.jsx | Yes | Generates a 300 ppi JPEG sub-asset for each page. The JPEG sub-asset is a real asset stored under the InDesign asset. It is also optimized and turned into a PTIFF by the DAM Update Asset workflow. |
| PDFPagesExport.jsx | No | Generates a PDF sub-asset for each page. The PDF sub-asset gets processed as described earlier. Because the PDF contains a single page only, no sub-assets are generated. |
You can configure the size of thumbnails by configuring those settings in the DAM Update Asset workflow. There are two steps in the workflow where you can configure the thumbnail size of image assets. Although one (Dynamic Media Process Image Assets) is used for dynamic image assets and the other (Process Thumbnails) for static thumbnail generation or when all other processes fail to generate thumbnails, both should have the same settings.
With the Dynamic Media Process Image Assets step, thumbnails are generated by the image server, and this configuration is independent of the configuration applied to the Process Thumbnails step. Generating thumbnails through the Process Thumbnails step is the slowest and most memory intensive way to create thumbnails.
Thumbnail sizing is defined in the following format: width:height:center, for example 80:80:false. The width and height determine the size in pixels of the thumbnail; the center value is either false or true and if set to true, it indicates that the thumbnail image has exactly the size given in the configuration. If the resized image is smaller, it will be centered within the thumbnail.
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- Thumbnail size for EPS files are configured in the EPS thumbnails step, in the Arguments tab under Thumbnails.
- Thumbnail size for videos are configured in the FFmpeg thumbnails step, in the Process tab under Arguments.
Image presets you create are available as dynamic renditions when you preview assets. By default, AEM shows 15 dynamic renditions when viewing an assets from Detail View > Renditions. You can increase the limit of renditions that display.
To increase the number of image presets displayed:
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If using Internet Explorer 9, creating a preset does not appear in the preset list immediately after saving. To work around this issue, disable the cache for IE9.
If you intend to support the ingestion of AI, PDF, and EPS files so that you can generate dynamic rendition of these file formats, you may want to review the following information before you create image presets.
See Adobe Illustrator (AI), Postscript (EPS), and PDF file formats.
If you intend to support the ingestion of INDD files so that you can generate dynamic rendition of this file format, you may want to review the following information before you create image presets.
See InDesign (INDD) file format.
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Enter values into the Basic and Advanced tabs as appropriate, including a name. The options are outlined in Image Preset options. Presets appear in the left pane and can be used on-the-fly with other assets.
To create a responsive image preset, perform the steps in Creating Image Presets. When entering the height and width in the Edit Image Preset window, erase the values and leave them blank.
Leaving them blank tells AEM that this image preset is responsive. You can adjust the other values as appropriate.
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In order to see the URL and RESS buttons when applying an image preset to an asset, the asset must be published.
When you create or edit image presets, you have the options described in this section. In addition, Adobe recommends some best practice options to start.
Adobe recommends these “best practice” option choices to start:
- Format (Basic tab)- Select JPEG or another format that meets your requirements. All web browsers support the JPEG image format; it offers a good balance between small files sizes and image quality. However, JPEG format images use a lossy compression scheme that can introduce unwanted image artifacts if the compression setting is too low. For that reason, Adobe recommends setting the compression quality (on the slider) to 75. This setting offers a good balance between image quality and small file size.
- Enable Simple Sharpening - Do not select Enable Simple Sharpening (this sharpening filter offers less control than Unsharp Masking settings).
- Sharpening: Resampling Mode - Select Bi-Cubic.
| Field | Description |
| Name | Enter a descriptive name without any blank spaces. Include the image-size specification in the name to help users identify this Image Preset. |
| Width and Height | Enter in pixels the size at which the image is delivered. Width and height must be larger than 0 pixels. If either value is 0, then no preset is created. If both values are blank, a responsive image preset is created. |
| Format | Choose a format from the menu. Choosing JPEG offers the following additional options:
Choosing GIF or GIF with alpha provides these additional GIF Color Quantization options:
Choosing PDF, TIFF, or TIFF with alpha provides this additional option:
Choosing PNG, PNG with Alpha, or EPS provides no additional options. |
| Sharpening | Select the Enable Simple Sharpening option to apply a basic sharpening filter to the image after all scaling takes place. Sharpening can help compensate for blurriness that can result when you display an image at a different size. |
| Field | Description |
| Color Space | Select RGB, CMYK, or Grayscale for the color space. |
| Color Profile | Select the output color space profile that the asset should be converted to if it is different than the working profile. |
| Render Intent | You can override the default rendering intent. Rendering intents determine what happens to colors that cannot be reproduced in the target color profile (out of gamut). The Render Intent is ignored if it is not compatible with the ICC profile.
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| Blackpoint Compensation | Select this option if the output profile supports this feature. Blackpoint compensation is ignored if it is not compatible with the specified ICC profile. |
| Dithering | Select this option to possibly avoid or reduce color banding artifacts. |
| Sharpening Type | Select None, Sharpen, or Unsharp Mask.
In Unsharp Mask, you have the following options:
Sharpening is described in Sharpening Images.
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| Resampling Mode | Select a Resampling mode option. These options sharpen the image when it is downsampled:
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| Print resolution | Select a resolution for printing this image; 72 pixels is the default. |
| Image Modifier | Beyond the common image settings available in the UI, Dynamic Media supports numerous advanced image modifications that you can specify in the Image Modifiers field. These parameters are defined in the Image Server Protocol command reference. Important: The following functionality listed in the API is not supported:
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In addition to the options available in the Basic and Advanced tabs, you can define image modifiers to give you more options when defining image presets. Image Rendering relies on the Scene7 image rendering API and are defined in detail in the HTTP Protocol Reference.
The following are some basic examples of what you can do with image modifiers.
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Some image modifiers cannot be used in AEM.
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If you have Feature Pack 14410 installed, you do not need to publish image presets. They are published automatically. Please note that Publish and Unpublish are not available as options if you have this feature pack installed.
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