How to Overlay Light Leaks in Kdenlive

Adding light leaks to your video footage is a great way to introduce a creative, vintage, or cinematic feel. In Kdenlive, this visual effect is achieved by placing a light leak video clip on a track above your main footage and utilizing the “Screen” composite mode. This guide will walk you through the step-by-step process of importing your assets, arranging your timeline, and applying the composite transition to seamlessly blend the light leak onto your video.

Step 1: Import Your Media

First, you need to bring your assets into Kdenlive. Drag and drop both your primary video footage and your light leak video clip (which should ideally feature light elements on a pure black background) into the Project Bin.

Step 2: Arrange the Timeline Tracks

For composition to work, the clips must be layered properly on the timeline: 1. Drag your primary video footage onto a lower video track (for example, V1). 2. Drag the light leak clip onto the track directly above your main footage (for example, V2). 3. Align the light leak clip so it sits directly above the portion of the video where you want the overlay effect to occur.

Step 3: Apply the “Composite and Transform” Transition

To blend the two tracks together: 1. Look at the timeline and select the upper clip (the light leak on V2). 2. Right-click the clip, hover over Insert a Composition, and select Composite and Transform. (Alternatively, you can go to the Compositions tab in the project bin area and drag the Composite and Transform transition onto the light leak clip). 3. A transition block will appear on the timeline linking track V2 to track V1.

Step 4: Change the Blend Mode to Screen

With the transition applied, you must now change how the layers interact: 1. Click on the yellow/purple transition block on your timeline to select it. 2. Look at the Properties panel (usually located in the top-right or top-left area of the interface). 3. Find the dropdown menu labeled Compositing or Blend Mode (which defaults to “Over”). 4. Click the dropdown and select Screen from the list.

Step 5: Adjust and Fine-Tune

Once “Screen” is selected, the black background of the light leak video will become completely transparent, leaving only the bright, colorful light elements superimposed over your original footage.

To customize the look further: * Opacity: If the light leak is too bright or distracting, adjust the Opacity slider in the transition’s Properties panel to fade the effect. * Duration: Trim the edges of the light leak clip on the timeline to control exactly when the effect starts and ends.