Import Multi-Channel EXR Sequences in Kdenlive

This article provides a step-by-step guide on how to import and map multi-channel OpenEXR (EXR) image sequences in Kdenlive. You will learn how to bring these high-dynamic-range files into your timeline and utilize Kdenlive’s built-in tools and effects to isolate and map individual channels, such as alpha or color passes, for your post-production workflow.

Step 1: Import the EXR Image Sequence

Kdenlive treats image sequences as single video clips. To import your EXR sequence:

  1. Open Kdenlive and go to the Project Bin panel.
  2. Right-click inside the Project Bin and select Add Clip or Folder (or press Ctrl + Shift + A).
  3. Navigate to the folder containing your EXR files.
  4. Click on the first image of the sequence.
  5. Check the Import as image sequence box at the bottom of the file dialog.
  6. Click OK. Kdenlive will compile the individual EXR frames into a single playable clip in your Project Bin.

Step 2: Add the Sequence to the Timeline

Once imported, drag the EXR sequence clip from the Project Bin and drop it onto a video track in your timeline.

Step 3: Map and Isolate Channels

By default, Kdenlive reads the standard RGB and Alpha (RGBA) channels of the EXR file. Because Kdenlive is a non-linear editor rather than a node-based compositor, it does not feature a dedicated multi-channel layer splitter. To isolate and map specific channels, you must use video effects:

  1. Go to the Effects tab.
  2. Search for the Color Channels or Extract Channel effect.
  3. Drag and drop the effect onto your EXR clip in the timeline.
  4. In the Properties panel of the effect, select the specific channel you want to map (such as Red, Green, Blue, or Alpha) to isolate that data.

Step 4: Workaround for Complex Multi-Layer EXRs (e.g., Depth, Specular, Normals)

If your EXR file contains advanced utility passes (like Z-Depth, Normals, or Cryptomattes) that do not map automatically to standard RGBA channels, you will need to prepare them:

  1. Duplicate the Clip: Stack the EXR clip on multiple timeline tracks (e.g., Track V1 and Track V2) to process different layers simultaneously.
  2. Apply Alpha Operations: Use the Alpha operations or Matte effects to map the greyscale values of a specific channel to act as a transparency mask for the track below it.
  3. Pre-Compositing Alternative: For highly complex multi-pass EXR files, it is highly recommended to split the channels into individual RGBA image sequences using a compositor like Blender or Natron before importing them into Kdenlive. This ensures maximum compatibility and performance during the editing process.