FAQs
Table of Contents
- Import Tool
- Run Time Issues
- Thumbnail Generation Fails on Large Files
- Why are my RAW images so dark?
- Some Properties in Sidebar are Unknown or Unavailable
- How can I inform you about bugs and wishes?
- What can I do if digiKam always crashes when doing something?
- How to deal with UTF-8 encoding issues?
- ExifTool not Found at Startup
- HEIF Metadata Not Updated
- Database
- Customizations
- Setup
- Workflow
- Contribute
🟠Skill Level: INTERMEDIATE
Import Tool
My Camera is Not in the List of Supported Devices
Can you add drivers for my camera?
digiKam does not include any camera drivers. It uses GPhoto2 to perform camera operations. If your camera is not in the supported list, try using it as a USB Mass Storage Device. This allows you to access the camera like a hard disk.
If you still have no luck, I recommend contacting the GPhoto2 project team.
How to Use a USB Mass Storage Camera
All modern Linux distributions are pre-configured to work with USB Mass Storage Devices. There is nothing you need to set up—it should be truly “plug and play.” If it doesn’t work, please report the problem to your distribution team.
Run Time Issues
Thumbnail Generation Fails on Large Files
Context: digiKam may fail to generate thumbnails for large files (over 1MB). When thumbnails are generated, those that fail appear first and are then replaced by the broken picture icon.
Solution: To fix this behavior, check if the application generating the file can include an IPTC or XMP preview as JPEG. digiKam uses this embedded image to quickly render the thumbnail without loading the entire image.
Why Are My RAW Images So Dark?
In 16-bit mode, users may be surprised to see relatively dark photographs after RAW conversion in digiKam, even if the ‘Color Management’ and ‘RAW Conversion’ options are correctly configured. The reason is that digiKam uses the Libraw demosaicing method with linear conversion of RAW data. If the ICC profile does not include gamma correction and/or tone mapping (common with Canon profiles), the result is dark. In 8-bit mode, gamma correction is applied automatically.
A RAW file is a container that includes raw sensor data, EXIF metadata, and often a JPEG preview thumbnail. It does not usually include an ICC profile. The embedded JPEG file is used by digiKam to display RAW image thumbnails or in slide shows, and it can be used for TV display from the camera. This is fast, but it is only a preview—no raw data.
RAW conversion requires several steps to produce a satisfying result:
- Choose the internal working space based on the intended use.
- Adjust the tonal range—define thresholds for highlights and shadows.
- Adjust gradation—adjust mid-tones, for example using numerical values in the histogram or curves.
- Alter white balance if necessary.
- Remove color cast ideally using color temperature (or an eyedropper tool) and a tint/tone slider.
- Apply smoothing and noise removal (if not done during conversion).
- Apply sharpening (refocus, unsharp mask).
- Choose the final color bit depth (saving as JPEG always reverts to 8-bit; use PNG or TIFF for 16-bit).
- Select output and pixel dimensions—upsampling on the RAW file often gives better results compared to already processed files.
- Continue editing, for example, retouching or small enhancements in your favorite imaging application.
Most profiles that come with camera OEM software are not suited for linear conversion. For a good profile, create one yourself or use a service. It will be more precise than the standard profile and will include gamma correction—no more dark images in 16-bit mode!
Some Properties in Sidebar Are Unknown or Unavailable
digiKam uses the Exiv2 library to display file properties. If the “Dimensions” value is “unknown,” it means the relevant file format is not yet fully supported by the library.
Note: Even if you have the “Dimensions” information, some other properties (bit depth, sensitivity, compression, etc.) may still be unavailable depending on the image file and your digital camera.
How Can I Inform You About Bugs and Wishes?
Please use the bug tracking system for all bug reports and new feature requests. You can check out the current bug reports and wishlists by following the instructions available here.
What Can I Do If digiKam Always Crashes When Doing Something?
It could be a problem with Exiv2 library, which is used throughout digiKam to manipulate file metadata. It is mandatory to use the latest stable version of Exiv2 with digiKam. All pre-compiled bundles provided by the project use the latest Exiv2 version tested by the team.
Check if your problem has already been reported by another user in the bug tracking system to prevent duplicate reports, which are time-consuming for the team to triage.
If it has not been reported, check the contribution page for instructions on how to capture and send a backtrace.
How to Deal With UTF-8 Encoding Issues
Context: After upgrading your Linux distribution, you may encounter a warning when starting digiKam about a change in character encoding. This is typically due to a UTF-8 encoding migration.
Solution: Most modern Linux distributions use UTF-8 by default for character encoding, including file content and file names. This issue is most likely to occur on Linux distributions released after 2010 or due to a migration to a file-system with better UTF-8 support.
For more information, see UTF-8 and Unicode.
digiKam will warn you if your locale settings change to a new encoding—for example, if you switch from ISO Latin1 (ISO8859-1) to UTF-8. You may see a message like this at application startup:
Your locale has changed from the previous time this album was opened.
Old Locale: ISO 8859-1, New Locale: UTF-8.
This can cause unexpected problems. If you are sure that you want to continue, click on 'Yes' to work with this album. Otherwise, click on 'No' and correct your locale setting before restarting digiKam.
Important: Before accepting this change, migrate at least the file names in your albums to UTF-8. Otherwise, you may encounter issues accessing directories containing non-UTF-8 encoded characters (such as accents).
ExifTool Not Found at Startup
Context: For unclear reasons that are not always reproducible, the ExifTool executable included in the bundles may not be found at startup, even if the ExifTool executable is present in the same directory as the digiKam executable.
Solution: Go to the Setup Metadata ExifTool page, click the button to locate the binary, and then restart digiKam.
HEIF Metadata Not Updated
Context: When the option to write metadata to files is enabled, HEIF metadata is not updated in the same way as JPEG metadata.
Solution: HEIF support in the Exiv2 metadata backend is limited. To achieve full metadata support for HEIF files, you have two options:
- Use the ExifTool metadata backend instead of Exiv2. ExifTool supports writing metadata to HEIF files. See this entry in the online documentation for details.
- Use XMP sidecar files to store metadata. This approach also supports writing metadata for read-only files, such as video media. See this entry in the online documentation for details.
Database
digiKam Does Not Work When the Album Library is on a Network Share
Context: digiKam freezes when the album library, based on an SQLite database, is located on an NFS server, NAS, or Windows shared folder. What can I do?
Solution: digiKam uses SQLite to store information about images (tags, comments, ratings, etc.). SQLite relies on file locking features provided by filesystems (check this FAQ entry). However, network file systems often have issues with locking, which can cause unexpected problems with SQLite.
To solve this problem, try using a symlink for the SQLite database file. This method links your entire album library to a network path.
Note: It is also possible to use MySQL or MariaDB as a database backend to solve this problem.
How to Import Tags from Another Program?
If your external program can generate a comma-separated values (CSV) file of the tags, digiKam 8.8.0 introduces a new option in the Tags Manager to import and export tag hierarchies in the Controlled Vocabulary Keyword Catalogue format. For more details, see the 8.8.0 release announcement.
If your external program supports XMP sidecar files, digiKam can scan sidecar contents to populate items in the database. This includes tag hierarchies and other metadata properties.
How to Migrate a Database Between Different Computers?
Context: You have an older computer running digiKam in production, referencing a large collection of items. You also have a new computer with a fresh installation of digiKam but an empty collection. The goal is to migrate the database (and the collection of items) from the old computer to the new one without rescanning all items.
Solution:
If you are using an SQLite database, simply copy the digiKam4.db file to the new computer. Ensure that the image collections are located in the same folder structure on the new computer. Then, update the base path using the “Update” function in the digiKam collection settings.
Customizations
How to Create a Color Theme
Color schemes are based on INI text file format, separated into sections and attributes defined by key-value pairs. The color specification uses the standard HTML color format (RGB/hexadecimal).
System-level installation of color schemes is done in $(INSTALLATION_PREFIX)/share/apps/digikam/colorschemes, and user-level installation is in $(HOME)/.local/share/apps/digikam/colorschemes under Linux.
Theme names appear in the menu with the filename. Make sure to capitalize the first letter of the filename. You do not need to restart digiKam if you modify the theme—just switch to a different theme and switch back. However, if you add a new theme, you will need to restart digiKam for the new theme to be recognized.
Color scheme files are the same as those used for the Plasma desktop. You can find all details here.
How Can I Change the Default External Video Player?
digiKam uses an embedded video player based on the QtMultimedia framework for better portability and to avoid external dependencies. You can call an external video player using the “Open With” context menu entry or by pressing ALT+double-click on a thumbnail.
Under Linux, start the Plasma system settings, then go to Applications/File Associations, and click on “video.” Here, you will see a list of file types and the applications that can open them.
For example, if you want to use another video player for .avi files, go to x-msvideo. The first application listed will be the default one.
How Can I Change the Text Font Size?
Start your desktop system settings, then go to Appearance/Fonts. Here, you can adjust the font size and choose another font.
Please note that this will change the font behavior for all desktop applications!
Note: digiKam also includes font settings to customize the icon view, tree view, and tooltips text size. Go to the digiKam control panel to change these settings.
How to Change the Single-Click Behavior on a Thumbnail
Go to the digiKam control panel in the Views/Icons section to change this behavior. Under Linux, the Plasma desktop allows you to change from single to double-click (and vice versa) in Workspace/Desktop Behavior by selecting “double-click to open files and folders.”
How Can I Change the Browser Used With the More Info Button From the Map Sidebar?
Under Linux, start your desktop system settings, then go to “Application/Default,” then click on “Web Browser” and choose “in the following browser,” where you can enter any command.
Is digiKam Available in My Language?
digiKam is translated into many languages, which can be used instead of the default English.
If you installed digiKam using your distribution package, language files should be included, and you can run digiKam in any supported language. digiKam should follow your desktop language settings, but you can override the default language using the Settings/Configure Language menu. digiKam comes with more than 30 different translations.
If you use a pre-compiled bundle, digiKam includes more than 30 different translations as resources, and you can use digiKam in any supported language.
See this page for details on how to switch to another language.
Setup
Why Are Many Data Files Downloaded at Application Startup?
These files are deep-learning models. They are loaded and used by the AI engine in digiKam to process:
- Face detection and recognition,
- Auto-tag assignment,
- Image quality parsing.
These files are mathematical representations of neural networks trained outside of digiKam by third-party teams. Due to their large size, they cannot be included in the standard package. Instead, they are downloaded or updated from a secure location hosted by the KDE project infrastructure.
Why Download of Data Files Fails at Application Startup?
When I start digiKam I get the pop-up asking if I want to download ‘Model Files’ but when I try and download them I always an error like this:
An error occurred during the download.
Connection closed
The file are hosted in the KDE project infrastructure and server availability isn’t consistent worldwide; you’ll be randomly redirected to a nearby server. If you try again, we’ll attempt to use an alternative server. However, we generally have no control over which server you’re redirected to or its availability. Try again at a different time of day.
Where Are All Configuration Files Used by digiKam Located?
Most configuration files for digiKam are stored in the user’s home directory. A complete list of these files and their purposes is available in this section of the online documentation, categorized by operating system. It’s hightly recommended to include these files in your backup strategy.
Why Do macOS and Windows Warn About Non-Signed Bundles?
We choose not to pay for an annual developer account with GAFA companies in order to sign the digiKam bundles. Developing for these operating systems requires significant effort, and we receive no support from GAFA for maintaining non-Linux systems. Since we refuse to pass these costs on to users, our bundles are not notarized. As a result, macOS and Windows security policies may display warnings when you attempt to install digiKam.
For instructions on how to properly install the application, see the online documentation for Windows and Apple (macOS) devices.
Workflow
Which File Format Should I Use?
Most digital cameras store images in JPEG format on the memory card. JPEG is a compressed format, and compression causes loss of quality. Heavy compression may make the loss of quality visible to the eye. Every time you open a JPEG image, edit it, save the file, and close it, the image is compressed, and quality is lost. Lost quality cannot be regained.
To avoid repeated loss of quality, save your edited files in a lossless format. digiKam supports two of these: TIFF and PNG. In digiKam, it is advisable to use PNG. digiKam supports Exif data in PNG files.
So, the recommendation is to save any edited files as PNG.
You have now finished editing your photos and are content with the results. Should you keep the PNG files or convert them to the much smaller JPEG files for storage? If you are very concerned about storage space, you can do the latter. However, it is better to keep the lossless PNG files and only create JPEG copies when you want to take your images to the print shop, send them by email, or post them on the web.
Note: A format with better compression named HEIF can be used instead of PNG to gain a better compression ratio.
You can see a detailed overview of file formats supported by digiKam here.
How to Copy Files Outside the digiKam Collection?
After finalizing your work, you may want to copy files to a removable media. There are two possible methods to do this:
- Open a file manager alongside digiKam, locate your removable media, and use drag and drop to transfer items from digiKam to the file manager.
- Use the File Copy plugin, available in the Export main menu, to transfer items with additional pre-processing options.
Contribute
digiKam Does Not Compile
First, check that you have the development files installed on your Linux system. digiKam depends on many libraries, and you must have the headers to compile it.
Linux distributions usually have -dev packages when you want to compile something against a specific library. For a list of required dependencies, see this page.
On Debian-based distributions (e.g., Debian, Ubuntu), you can install the required packages with:
sudo apt-get build-dep digikam
If there are warnings about unsermake, set the $UNSERMAKE environment variable to “no.” For example:
export UNSERMAKE=no
If you still have problems, check the support page.
digiKam Mixes English and My Native Language in the Main Menu
If English words appear in the application interface even after setting the language to a non-English option, this is likely due to incomplete translations by the KDE translators team. Please remember that translators are volunteers who dedicate their free time to improving internationalization in open-source projects.
Translations are not a task for developers, but everyone can contribute to completing language support in digiKam. To help, please follow the instructions here to get started.
A Section of the Documentation Is Incomplete or Does Not Exist Yet
The digiKam online documentation is maintained by contributors and is not a developer-specific task. If you have skills in sharing knowledge, explaining concepts, teaching, or writing, we encourage you to join the effort and follow the instructions here.
Note: The online documentation is also translated, and we welcome help for this task as well.
