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Generate thumbnails

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Learn how to use custom thumbnails and change thumbnail images in the Project Client.

Thumbnails are the small images that appear when you browse or search a collection. Thumbnails also are displayed when working with items in the Project Client.

When images and PDF files are added to Project Client projects, CONTENTdm tries to generate thumbnail representations of the items. For image files, such as JPEGs, the Project Client uses a scaled-down version of the image itself. By default, CONTENTdm also automatically creates thumbnails for other file types.  This setting can be changed by using the Project Settings Manager.  If the Project Client is unable to generate a thumbnail, the Project Client uses a standardized thumbnail to represent the file type.

You can create custom thumbnails for individual items, or edit Images and thumbnails in the Project Settings Manager to edit the standard thumbnails and associated file types or add your own standardized thumbnails.

When you are ready to create predefined queries in a collection, you can specify that the search results display only titles without thumbnail images. To learn more about creating queries, see Custom Queries and Results.

Using custom thumbnails

CONTENTdm provides you with the ability to use custom thumbnails rather than the thumbnails that are generated by the Project Client when you add items to your project. Custom thumbnail images are especially useful for documents, videos, and audio files when a small representation of the item itself may not be immediately recognizable. Any thumbnail image within CONTENTdm can be replaced with your own custom thumbnail.

Custom thumbnail images must be created outside of the Project Client and should be sized no greater than 160 pixels wide and 120 pixels high. If the image is larger than 160 x 120 pixels, it will be resized so that it does not exceed those dimensions.

You can specify a custom thumbnail by editing an item in your project spreadsheet. You can also specify custom thumbnails when you are adding multiple files.

Creating a custom thumbnail directory

Custom thumbnails must be JPEG files. Thumbnail dimensions must be no larger than 160 x 120 pixels. If larger, the thumbnails will be resized. A custom thumbnail is not required to have the same base file name as its associated image.

  1. Create a directory in an area accessible by the Project Client. This is usually on the same computer as the Project Client or on a mapped network drive.
  2. Move custom thumbnails into the newly created directory.

Replacing thumbnails when editing an item

The item must already be in the project spreadsheet.

  1. On the Project tab, find the thumbnail you want to replace, right-click the thumbnail and select Replace Thumbnail. The Replace Thumbnail dialog displays.

    Alternatively, if you have opened the item for editing in a new tab, you can access the Replace Thumbnail dialog by clicking Change Thumbnail in the left task bar under Item Editing Tasks.
  2. Browse to the image to use as a custom thumbnail.
  3. Select the image and click Open.
    1. The thumbnail that you select must be less than 160 pixels wide by 120 pixels high.
  4. The Replace Thumbnail dialog box shows the new thumbnail.
  5. Click OK to save the new thumbnail. The Replace Thumbnail dialog closes and the new thumbnail image displays in the project spreadsheet.

Using custom thumbnails while adding multiple items

If you want to use custom thumbnails when adding multiple items, you must first specify those thumbnails by using the Project Settings Manager before adding the items.  See Images and thumbnails for more information. 

  1. While using the Add Multiple Files wizard, click Image Options from the Display Image Settings screen. The Project Settings Manager displays with the Images and Thumbnails page selected.
  2. Click Thumbnails. The Thumbnail Manager displays.
  3. Uncheck Turn on automatic thumbnail creation for all other file types.
  4. Review the Thumbnail Selections by File Type. Add or edit the file types you will be importing.
    1. To add a file type, click Add.
    2. To edit the thumbnail for a listed file type, click the file type row to select and then click Edit. The Edit Thumbnail Mapping dialog displays.
  5. Click Choose Thumbnail to browse to the thumbnail to associate with the selected file type. Click Open and then click OK to close the Thumbnail Mapping dialog and display the Thumbnail Manager with the updated thumbnail.
  6. Click OK.
  7. Close the Project Settings Manager to return to the wizard and the Display Image Settings screen.
  8. Click Next to continue with the Add Multiple Items wizard.

 Note: If you do not want the custom thumbnail to always apply, be sure to return to the Images and Thumbnails page after you add the files and edit these settings.

Changing thumbnail images

When you add items to a project, CONTENTdm generates scaled-down versions, or thumbnails, of the images or files for use within the project and within search results. Thumbnails are generated automatically for JPEG, GIF, TIFF, JPEG2000, PDF. However, with some types of items, such as music, oral histories, or documents, when the Project Client cannot generate a thumbnail for a specific file type it may be more useful to have thumbnail images that represent all oral histories or all documents within a collection.

Using the Thumbnail Manager, you can create and edit associations between thumbnail images and one or more file types, or add your own representational images to the Thumbnail Manager. This way, if you have automatic thumbnail generation turned off, then whenever you add a specified file type to a project, a predefined thumbnail image is generated for that file type.

The preset thumbnail images and file extensions within the Thumbnail Manager may be edited, updated or deleted with the exception of the Default thumbnail image, which can be edited but not deleted. The Thumbnail Manager provides preset thumbnail images for the following file types:

Image File types
Video avi, flv, mov, mp4, mpg, qt
Audio wma, mp3, wav
PDF pdf
URL URL, null items
Microsoft Word doc, docx
Microsoft Excel xls, xlsx
Microsoft PowerPoint ppt, pptx
Zipped File zip
Digital File Default, any undefined file extension

Adding a thumbnail to the Thumbnail Manager

Images added to the Thumbnail Manager must be saved in JPEG format and may not be larger than 160 pixels wide or 120 pixels high.

Changes made within the Thumbnail Manager apply to the current project. To replicate these changes in other projects you must repeat the steps while working in those projects.

  1. From the Home tab or the Project tab, click Edit Project Settings. The Project Settings Manager displays.
  2. Click the Images & Thumbnails tab. The Images & Thumbnails page displays.
  3. Click Thumbnails. The Thumbnail Manager displays.
  4. Click Add. The Add Thumbnail Mapping dialog box displays.
  5. In the Media Type text box, enter information about the types of media this thumbnail will be associated with. This information will not appear on your image.
  6. In the Extensions text box, type the file extensions that you wish to associate with the image. Separate multiple file extensions with a comma. For example: wav, mp3, wmf. The same file extensions may not be used twice within the Thumbnail Manager.
  7. Click Choose Thumbnail. The Open File dialog box displays.
  8. Select the thumbnail you want to add and click Open. The new thumbnail image appears in the Add Thumbnail Mapping dialog box.
  9. Click OK. Then, click OK to close the Thumbnail Manager.

When you add the specified file types to the project, the new thumbnail image will be used as a thumbnail representation for that file type if the Project Client cannot generate one automatically or if you have turned off the automatic thumbnail creation option in the Project Settings Manager. These changes will apply only to the current project.

Editing extensions in the Thumbnail Manager

With the Thumbnail Manager, you can replace the thumbnail images for specified file types and add or edit file extensions associated with thumbnails.

  1. From the Project menu in the Project Client, select Project Settings Manager and then select Images & Thumbnails. The Images & Thumbnails page displays.
  2. Click Thumbnails to display the Thumbnail Manager.
  3. Select the row of the thumbnail you want to edit. Click Edit. The Edit Thumbnail Mapping dialog box opens.
  4. Make changes directly in the Media Type or Extensions text boxes or replace the existing image by clicking Choose Thumbnail.
  5. Click OK to save your changes. Then click OK to close the Thumbnail Manager.

    These changes will be applied to all subsequent additions to the current project.

Deleting a thumbnail from the thumbnail manager

  1. From the Project menu in the Project Client, select Project Settings Manager and then select Images & Thumbnails. The Images & Thumbnails page displays.
  2. Click Thumbnails to display the Thumbnail Manager.
  3. Highlight the thumbnail image you want to delete.
  4. Click Delete. The thumbnail is deleted from the project.
  5. Click OK to close the Thumbnail Manager.