17.7. Viewing and Editing Images

digiKam comes with a comprehensive image viewing and editing suite consisting of various plug-ins. To enter digiKam's viewing or editing mode, right-click an image thumbnail and select View or Edit from the context menu. To use the plug-ins, you need to install the digikamplugins package.

Use View to zoom in and out of your image or to start a slide show with a selection of images or all images in your album/collection. Use Edit to open the selected image in editing mode and to use all the editing options introduced below.

The toolbar in the image editing mode of digiKam contains some of the most frequently used basic editing options:

17.7.1. Applying Image Decorations

Use the Decorate menu to superimpose various kinds of graphics and text effects on your images without having to bother about filters and their fine-tuning:

Apply Texture

Select the type of texture you want to apply to your image and determine how prominent this texture should be (Relief). digiKam applies the texture and saves the changes to the original copy of your image.

Add Border

Select the type of border. Depending on the type of border you have selected, choose one or two colors to be used for the border and set the width of the border around your image. digiKam creates the border and saves the changes to the original copy of your image.

Insert Text

Enter the text you want to superimpose on the image, choose font, font style and size. Select the text justification and decide whether the text should be rotated and to what degree. Add an optional border and semi-transparency. digiKam adds your text layer to the original image.

Template Superimpose

Just as you can superimpose any text on your image, you can also apply ready-made templates to create funny greeting cards, posters and the like.

17.7.2. Manipulating Color Settings

The Color menu allows you to manage all kinds of different color-related settings. Its capabilities range from simple auto correction mechanisms to full-blown color management via color profiles:

Auto Color Correction

If aiming for a straightforward color and exposure correction of your image, try this option. Choose from various preset modes and apply the one that matches best. Use the histograms to determine whether the result matches your needs.


This tool offers a simple way of fixing over or underexposed images.


This tool helps you to optimize images that have been taken under very bright lighting conditions and appear somewhat washed out. Bring color saturation back to these images by manipulating the hue and saturation sliders. Depending on the level of color, you might also want to adjust the lightness to prevent the image from registering too dark. Of course, you can also use this tool to achieve the opposite effect if you need to brighten up an image that has been taken at low light conditions and contains far too much color saturation.

Color Balance

Depending on the lighting conditions under which an image was taken or the quality of an image scan, the colors may appear somehow out of balance. Using the color balance tool, you can try to shift the balance towards another end of the color spectrum.


Invert the color values.

Black & White

Transform your color image into a black and white one. Use the Film, Lens Filters, Tone, and Lightness to tweak the end product. The Film tab offers you to emulate the effects various black and white films. To emulate color filters used with the camera lens, use the Lens Filters tab. Note that you can only apply one filter at a time. Using the Tone tab you can have your black and white image tinted in a particular way (sepia, for example).


Determine the color depth (in bit). Transform 8-bit into 16-bit images and vice versa.

Color Management

Color management via ICC color profiles helps you maintain color fidelity across multiple output devices (camera, display, printer).

Levels Adjust

Use this option to control multiple levels and to check the resulting image in just one tool. It lets you save the level settings you chose and thus enables you to apply the same corrections to multiple images if needed. This comes in handy if you know that your camera tends to use the same faulty color settings all the time and you would like to be able to correct them with just a single click.

Color Effects

This tool offers a selection of color effects like edge finding, solarizing, etc.

White Balance

Every source of light registers differently on your digital camera's chip. Depending on the light source, the color temperature tends to register either warmer (towards the red end of the spectrum) or cooler (towards the blue end of the spectrum) than standard daylight. Most cameras ship with preset white balance schemes that try to compensate these effects. If the resulting images registers faulty, use the white balance adjustment provided by digiKam. Either manipulate the color temperature directly by using the Kelvin slider or choose one of the preset white balance schemes.

Curves Adjust

This tool allows you to basically perform any operation available through the Brightness/Contrast/Gamma and the Levels Adjust tools, but in one tool and using free-function mapping. Therefore this tool is more powerful and flexible than the other two, but it may take some time to get used to its handling.

Channel Mixer

The channel mixer tool provides an alternative way of converting colored images to black and white. Using the Monochrome option and the channel sliders, you can selectively determine how much each of the color channels contributes to the overall image. The channel mixer option is much more flexible than the standard conversion to black and white, because you can manage each color channel separately.

17.7.3. Fixing and Tweaking Your Images

Use the Enhance menu to address a number of common defects related to digital imagery:


Tweak the sharpness of your image or smooth it.

Red Eyes

Reduce or eliminate red eyes caused by use of a flash.


Heal“ defective areas of your image.

Noise Reduction

Remove artifacts, such as those caused by dust on your lens or sensor. Compensate for pixel noise caused by high ISO settings of your digital camera and reduce noise and artifacts in low quality scans.

Hot Pixels

Detect and erase problem pixels of your image caused by defective pixels of your camera's sensor.

Lens Distortion Correction

Compensate for barrel and pincushion distortion of your images caused by the use of strong wide-angle or telephoto lenses.


Provides an all-inclusive treatment to images suffering from all sorts of digital defects, such as noise and scratches.

Anti Vignetting

Compensates circular shades (vignettes) at the edges or in the center of your image that were caused by the use of strong wide-angle or telephoto lenses.

To observe the functionality of the Fix options, look at Inpainting, for example. Assume some dust or scratch on your lens ruined an image. To remove this kind of artifact, proceed as follows:

  1. Open your image.

  2. Use the mouse cursor to select the area to which to apply the fix.

  3. Select Enhance+Inpainting or press Strg-E.

  4. Determine the method to use to remove the artifact:

    • Choose one of the preset options (Remove Small Artifact, Remove Medium Artifact, or Remove Large Artifact) and proceed with Schritt 6.

    • Set the filter parameters on your own. Proceed with Schritt 5.

  5. If you opted against using any of the preset filters (in the Preset tab), open the General and Advanced Settings tabs and adjust the settings to your needs.

  6. Click OK to apply your settings and modify the image accordingly.

    [Tip]Creating and Reusing Your Own Filter Settings

    If you need to use the same set of settings more than once, for example, if a scratch on the lens ruined an entire series of images, create your set of filter settings. Save them for later use by clicking Save As and saving them to a text file. For subsequent images, open the Image Inpainting dialog, click Load, then select the text file and apply the filter settings with OK.

Abbildung 17.5. Using Inpainting to Remove Artifacts

Using Inpainting to Remove Artifacts

17.7.4. Applying Image Transformations

To scale or rotate an image, use the Transform menu:

Rotate, Flip, Free Rotation

Rotate your image to a certain degree. Rotate rotates by multiples of 90 degrees. With Free Rotation, specify any angle you want.

Crop, Aspect Ratio Crop

Crop your image. Crop cuts to any rectangular selection on top of your image. Aspect Ratio Crop crops the image following various sophisticated design principles.

Perspective Adjustment

Adjust the perspective of an image. For example, if you notice some odd angles in shots containing vertical or horizontal lines, use this tool to set them right. Grab any of the four handles to the corners of your image and move them as much as needed. Use the Crop tool to remove the resulting black edges of your image and to trim it down.


Shift one part of your image to one direction and the other to the opposite direction, either horizontally or vertically. Specify the angles for vertical and horizontal shear and use Crop to trim the resulting image.


Scale your image. Resize offers a simple interface allowing you to manipulate your image size by pixel or percentage. Select whether to keep the aspect ratio. If you select Restore photograph, you can fine-tune the algorithms used to on your resized image and improve the quality of the end product. Note that this option might be considerably slower than a simple resize operation.

Assuming you have an image that is otherwise perfect, but you are not entirely satisfied with the composition yet or need to crop your image to match a certain paper format for reproduction. In this case, use Aspect Ratio Crop and proceed as follows:

  1. Open your image.

  2. Select Transform+Aspect Ratio Crop.

  3. Determine the orientation and aspect ratio to use:


    Specify a free crop of the image using the X, Width, and Y, Height sliders.


    Select a custom ration of width versus height instead of using one of the preset values.

    X:Y Ratio

    These ratios match most of the common paper sizes used to print photographs. Pick the one that suits your purpose best.

    Golden Ratio

    A ratio (1:1.618) that is traditionally used by artists and architects to create harmonious results.

    Use Max. Aspect to set the crop area to the maximum possible size of the ratio specified.

  4. After determining the size of your crop selection, optionally apply compositional rules to it. The Composition Guide helps to create a crop selection that results in a visually pleasing image. Dotted lines are displayed that guide you to a better composition of your image.

    [Tip]For More Information

    For a comprehensive description of the options, refer to http://docs.kde.org/stable/en/extragear-graphics/digikam/using-kapp-imageeditor.html.

  5. If the position of your crop does not follow the compositional rule to your satisfaction, move it.

  6. Click OK to apply your crop selection and trim your image.

Abbildung 17.6. Creating a Custom Crop Using Aspect Ratio Crop

Creating a Custom Crop Using Aspect Ratio Crop

17.7.5. Applying Filters and Effects

You can select from a variety of basic effects and filters to apply to your images to give them a more artistic or over-the-top look:


Apply raindrop effects to your image. Determine the size and number of the drops and finally specify the degree of distortion caused by the drops (Fish eyes).

Infrared Film

Simulate the use of infrared film to achieve a slightly surreal effect. The result is strikingly different from the original image. Add additional film grain and tweak the sensitivity (ISO) to achieve a more artistic feel.

Oil Paint

Simulate an oil painting. Determine the brush size and the degree of smoothing to apply to your image.


Pretend your image had been embossed to a sheet of paper. Choose an appropriate depth.

Distortion Effects

Apply various strange distortion effects, such as fish eyes, to your image. Determine type, level, and repetition.

Add Film Grain

Add film grain to your image to give it a rough look.

Blur Effects

Blur your image to simulate the image being out of focus or to mimic any kind of movement that was not there when you took the image.

Charcoal Drawing

Transform your image into a black and white charcoal drawing. Choose an appropriate pencil size and determine the degree of smoothing to apply to the image.

Abbildung 17.7. Simulating IR Photography

Simulating IR Photography