Rotating thumbnails

Sometimes Daminion displays preview thumbnails with incorrect orientation.

This can happen particularly with scanned images or pictures taken in portrait format with a digital camera when image orientation fails to be recorded in the EXIF ​​data.

Daminion recognizes EXIF ​​data when importing files. When the data is missing, thumbnails are generally displayed horizontally.

In Daminion, thumbnails with inappropriate horizontal orientation can be rotated manually. The new orientation information is then stored within the catalog, but not within the images. This means that in other applications the image will still be displayed with default horizontal orientation. To find out how to change this information and store it within the file itself, please refer to Write and read tags to and from file.

How to rotate thumbnails

To change thumbnail orientation, select one or multiple thumbnails in the Browser window, click the arrow icon in the upper right corner of any thumbnail and select the desired rotation.
Alternatively, you can rotate thumbnails with the following keys:

[F3] key – to rotate counterclockwise

[F4] key – to rotate clockwise

Types of thumbnails

All files imported to Daminion are displayed differently in the Browser window depending on file type and status.

All possible types of displayed thumbnails are given below.


All image file formats as well as other file formats that have an integrated thumbnail or support thumbnail embedding (e.g. TIF, JPG, or PDF) are displayed with the corresponding thumbnail preview.





File formats that have no built-in thumbnail preview are shown with the default icons of file format.




By default, unknown file formats, which have been added manually, are displayed with a big question mark.

To find out how to assign a custom preview thumbnail to unknown file formats please refer to Add Custom Thumbnail



A broken chain thumbnail is displayed when Daminion doesn’t have access to the folder where thumbnails are stored or the thumbnail is damaged. In the latter case, select an image and try to rebuild the thumbnail by pressing CTRL+B.





If the original files have been deleted, moved or renamed outside Daminion, the thumbnail preview displays a small question mark in the upper-left corner.

The question mark is also displayed on thumbnails whose original files are stored on devices that have been disconnected from the PC. In these cases, Daminion cannot locate the original files, and therefore marks them as offline. Once the external storage device is reconnected, the original files are available again. However, sometimes you may need to update the thumbnails manually to make the question mark disappear. To do this, select all the items with question marks and press Ctrl + B.

When the offline file is opened in full-screen mode, it is displayed in low resolution with the notification The file “filename” is offline or missing in the bottom of the screen.

To find out how to relink particular folders or items, please refer to Relink Folders and Files.


Adding support for quality AutoCAD (DWG/DXF) thumbnails

Daminion can import AutoCAD DWG and DXF files, but it’s hard to find the right drawing visually because the preview of these files is a default icon rather than a quality thumbnail.

However, if you download and install the free DWG TrueView from the AutoDesk you will be able to view quality thumbnails your AutoCAD DWG and DXF files, not only in Windows Explorer but also in Daminion.

AutoCAD thumbnails that still appearing as default icons can be rebuilt in the following way from the Daminion menu: Item > Rebuild Thumbnail (Ctrl + B)

If the thumbnails are still not displayed, make sure Windows is set to display thumbnails:

  1. Go to the Windows Control Panel > Folder Options > View tab.
  2. Uncheck “Always show icons, never thumbnails” and click OK.
User-added image
After that, rebuild the thumbnails by selecting the files and clicking Ctrl+B in Daminion.

Adding support for quality Cineform Video thumbnails

To display thumbnails of videos encoded with the Cineform codec in the Daminion please do the following:

For Local Catalogs

1. Download this zip file
2. Unpack it and copy the and RegCineForm.bat files into the following folder:
c:\Program Files (x86)\Daminion Software\Daminion\MediaProcessors\VideoProcessor\codecs\
for your Daminion Standalone version.
3. Run the RegCineForm.bat as the Administrator

For Shared Catalogs

1. Download this zip file
2. Unpack it and copy the and RegCineForm.bat files into the following folder:
c:\Program Files (x86)\Daminion Software\Daminion Server\MediaProcessors\VideoProcessor\mplayer\codecs
on the PC where the Daminion Server is installed.
3. Run the RegCineForm.bat as the Administrator

Now all newly imported Cineform video files will be displayed with quality thumbnails. To update the thumbnails of already imported Cineform files with the default video icon, select these videos in the Daminion and press Ctrl + B.

Accelerating preview of large images

Huge images in Camera RAW, TIFF, PSD and BMP formats are now cached as JPEG previews and can be viewed at the same speed as regular JPEG images. This is especially noticeable when images are very large (more than 300 MB) or located on networks with lower bandwidth connections.

This option is turned on by default but can be switched off via program Preferences. When this feature is enabled, thumbnail generation and import speed will be slower, but the previewing of large images will be much faster and it will also reduce CPU load of the Server PC .

To change this option, do the following:

For Local catalogs:

  • Launch your Daminion Standalone version
  • Go to the main menu: Edit > Preferences
  • Switch to the Accelerate Preview option

For Server catalogs:

  • Launch the Daminion Server Administration panel on your server PC
  • Go to the main menu: Administration > Preferences
  • Switch to the “Accelerate Preview” option

If the “Accelerated preview of large images” option is checked, Daminion will also store full-size JPEG previews of large images when rebuilding thumbnails.

You can limit the maximum size of JPEG images by turning on the “Limit maximal JPEG preview size” option. For example, with 100 Megapixels limit your JPEG previews can have maximal sizes of 10000×10000, or 20000x5000pх, etc…


Which media formats does this option works for?

It works for Camera RAW, PSD, TIFF and BMP formats only.

Where will my JPEG previews be stored?

For local catalogs:  in the ~Thumbs\preview folder in the same folder as your local .dmc catalog.

For shared catalogs: in the “preview” sub-folder of the folder that was selected to store the thumbnails from your server catalog. This can be checked or configured via the Daminion Server Administration panel individually for each catalog.


Thumbnail Grouping

In your browser, you can create groups of thumbnail previews in which a series of associated images are represented by one thumbnail.


Grouping Thumbnails

First, select at least two thumbnail preview images in the Browser. Now you have three ways to take the images in a group.


Click with the right mouse button on one of the thumbnails. It opens a context menu as shown in Figure below.

Click Grouping and then in the sub-menu click Group. The selected images are now grouped together and represented by the thumbnail image you clicked to run the command.


If you select two or more images and then move the mouse over the top right corner of the thumbnail previews, a small clickable Group Selected Items icon appears.

Grouping thumbnails with the grouping icon

(click to enlarge)

The picture you run the command on becomes the thumbnail preview image of the group.


Select two or more images and then press Ctrl + G to group them together.

Diaplay of image count in a group


All four images are now grouped together and the number of items in the group appears in the top right corner of the thumbnail.






Collapse and expand a group

Expand and collapse a groupe with the mouse button


Move the pointer back to the top right corner of the thumbnail preview, where the number of items is normally displayed. As the pointer hovers over it, the number changes to an arrow symbol. Click the arrow to expand and collapse the group.

Alternatively, use the keyboard shortcut Ctrl + D.





Right-click a group of pictures and choose Grouping > Ungroup. Alternatively, use the keyboard shortcut Ctrl + Shift + G.

Ungroup a Group with the context menu

(click to enlarge)

The group is now broken up into individual items.

 Splitting a group

You can also split an existing group into smaller groups.

Expand the appropriate group, right-click the images that you want in the new group, and then select Grouping -> Split Group.

Choose a display picture for the group

You can choose which image is used as the preview thumbnail for a group.

Expand the group, right-click your chosen image and select Grouping -> Move to Top of Group.

Remove images from the group

Expand the appropriate group, right-click the image you want to remove from the group and choose Group -> Move Out of Group.

Compare Items

Compare Items view allows you to quickly find the right image from a series of similar images. You can exclude, select and/or rate images. And you can zoom all images simultaneoulsy with just one click – useful for quickly identifying the sharpest image in a series.

Launching Compare Items View

Select the photos you want to compare (from 2 to 8 images at a time).

In the file menu, navigate to “Item” and then click “Compare Items“.

(click to enlarge)

AUse this button to switch between multi- and single-view. When the button is pressed in, only one inage is displayed, thus allowing you to use the function buttons F1 through F8 C to switch quickly between the respective images.

BClick this button to display additional file information: file name, shooting date, image size and recording parameters.

To close Compare Items view, click the X button D or press the ESC key.


The taskbar above the images

Each of the images on display has an individual taskbar above it. 




 Displays the candidate’s number.

Click the Make Master button to anchor the respective image in the top left corner of the first window. The image can only be replaced by clicking Make Master above another image in the film strip.  

 Use this button to reject an image and hide it from the display. Once rejected, the image is replaced by the next one in overall selection. In addition, a red ‘no’ symbol marks the image in the filmstrip. 

 Rate your images here.

 Flagging – described in  Flagging an Item.

 Use the Close button to close the respective sub-windows. Doing this allows you to eliminate unsuitable images one at a time until you are left with two best images. 

The filmstrip at the bottom of the screen displays all images currently present in browser window.

In addition, the images currently displayed in the viewports above are marked respectively in the filmstrip. The “M” stands for Master (your choosen candidate) and the numbers #1#8 are the respective candidates currently on display in the viewport.

The currently selected image is displayed in the viewport within a white frame. You can replace this image, either by rotating the mouse wheel or by clicking on another image in the filmstrip.

Zoom View

Hold the mouse pointer over any one image and click to view all images at 100% magnification. Then use the mouse pointer to move all images simultaneously to help you identify the most appropriate candidate.

(click to enlarge)


Customizing Thumbnail Captions

By default, Daminion is configured to display file format above the thumbnail with an additional three lines below it displaying file name, size and exposure.

However, there is nothing to stop you from changing what metadata is displayed above and below your thumbnail previews.


At the bottom right of the main window, click the “i” symbol (see screenshot below).








You can also open the dialog box via the file menu by clicking View -> Customize Thumbnail Captions  or by right-clicking the bottom caption of the image and selecting Customize Thumbnail Captions.

This opens the Customize Thumbnail Captions dialog box.


Information above Thumbnails

Select which information should be shown above the thumbnail by selecting one item from the drop-down list.

Information below thumbnails

This shows the list of the tags currently displayed below the thumbnail.


Click Add to choose from a list of other tags that can be displayed below the thumbnail.


Use Delete to remove tags that should no longer be displayed.


Use the up and down arrows to rearrange the sort order of the tags.

Once you have made your selection, click OK to close the dialog box. Thumbnails will be displayed in the browser according to your new settings.

Adding Custom Thumbnails

Assigning custom thumbnails to unknown file formats in Daminion.

Daminion shows thumbnail previews of all imported files. For image files, the preview is a bitmap of the image; for video files it’s the first frame of the video sequence.


Unknown file formats added manually to Daminion’s import list are shown as a default preview (like the “unknown” manually-added VOB video file in the screenshoot to the left).





Daminion allows you to change this default preview to a more meaningful image of your own choice.

In order to import and manage these files, you must first add the unknown format to Daminion’s list of imported filters, as described in the chapter Adding an unknown file format.

A standard preview thumbnail is displayed for manually added file formats, either because Daminion does not know the structure of the particular file format and is therefore unable to read the embedded preview, or because this type of file doesn’t generally contain a preview image.

In order to display a meaningful preview, the imported file must be accompanied by a specially named jpeg file.

Let’s say you have a VOB video file, and you want Daminion to display it with your own thumbnail. First of all, select a jpeg image for Daminion to use as the thumbnail preview.

In our example, we chose a jpeg file, ferris_wheel.jpg, whose name and image are closely associated with the video content. The jpeg and the video file must be stored in the same folder.

For Daminion to use your jpeg file instead of the default preview, you must rename the jpeg in the following way:



Replace the first part, filename.ext, with the name of the video file. In our case, this gives us footage.vob.thumb.jpg


Now, when you import this video file, Daminion automatically looks in the source folder for a jpeg file that fits this naming convention. If such a file exists, it is automatically used as the preview thumbnail for this imported video file.

You can also use this method to create custom thumbnail previews for files you have already imported. To do this, choose a suitable jpeg, place it in the same folder as the file you’d like it to represent and follow the renaming procedure as explained above. Now, select the file to be linked to the jpeg thumbnail and press Ctrl + B. Daminion will update the preview for this file and incorporate the new custom thumbnail.