Installation

Install as a Blender extension.

1. Download the zip file for your platform. Then drag and drop the .zip file into the Blender window:

Optionally, verify that the rhubarb executable is working by pressing the Check rhubarb version button:

Blender before 4.2

1. Make sure to download the correct zip file for your operating system. For example: rhubarb_lipsync_ng-Windows-1.4.0.zip for Windows.

2. Run Blender, go to the Main menu/Edit/Preferences/Addons. Click the Install button (top right) and select the downloaded zip file (don't unzip the file).

1. After a short moment, the plugin will install and show up. Enable the plugin by ticking the checkbox in front of the plugin name.

2. Verify the rhubarb executable is working by pressing the Check rhubarb version button. Note the plugin wraps the executable from the rhubarb-lip-sync project.

Note: Generally, each time you see a button is disabled, hover the mouse cursor over the button and a popup will show the reason.

1. There should now be a new RLSP tab visible in the 3D view with two panels. First, create a new Capture in the current scene by pressing the Create capture button in the RLSP: Sound setup and cues capture panel.

2. Select a sound file.

   • Note the plugin can convert sound files to the supported formats.
   • For a better experience: Enable Audio Scrubbing Cache and Sync to Audio.
   • Optionally, place the sound strip in the Sequencer by pressing the Place as Strip button. You can set the start frame here, but if you change the start frame later, you need to remove the strip and place it again.

3. Press the Capture button. The list of Cues should get populated. Note:

   • The capture task runs in the background, so you can still use Blender while it is running. You can even create and run another capture(s) concurrently. However, pressing Esc will cancel the running operator.
   • The underlying rhubarb cli is also able to utilize multiple threads, but only for longer sound clips. It runs single-threaded for short sounds.
   • There are additional capture options available when pressing the small ⌄ button beside the Capture button, such as extended-shapes usage or Dialog file. The dialog file is a sound transcription that can improve accuracy, but only works for English.

4. You can preview the captured cues by clicking on the cue lists. Too short or too long cues are highlighted in red. You can also start playback, and the small icon will follow the cues. However, there is probably some refreshing bug, and sometimes the icon doesn't refresh unless the mouse cursor is moving over the panel.

1. Open the other panel RLSP: Cue mapping and baking and select the Object you want to animate. For bone animation, select an armature. For shape-key animation, select a mesh.

2. For each Cue type, select the appropriate Action. Note:

   • Use the ? button to show a hint about the expected mouth shape (copied from the rhubarb-cli page).

   • Usually, your Actions would have a single keyframe on the first frame (a.k.a. pose). But multi-frame actions are supported as well.

   • It is possible to map the same Action to multiple Cue types. For instance A and X.

   • Using Action-sheet where multiple cues are on different frames of the same Action is supported too. Use the custom frame range button to select the desired (sub)range:

     

   • There are action-filters available that can be used to narrow down the selection in the dropdowns. Use this, for instance, if all your poses are flagged as an asset. Or if you want to make invalid Actions (with a missing key) show up as well.

     

3. Select or create NLA Track. For 2D animation use a single track. But for 3D two tracks are preferable since it allows the placed Action strips to interleave and fluently blend their influence.

   

4. You can tweak the Strip placement settings. For 2D animation the In Out Blend Type should be No Blending

   
   

   
   

1. Press the big Bake to NLA button. This will bring up an additional dialog with a few more baking options and information:

   

   • Select the Capture (cue list) to be baked. It matches the one selected earlier in the RLSP: Sound setup and cues capture panel. Note it is possible to bake multiple Captures and bake them one-by-one reusing the same mapping.
   • You can again set/change the Start Frame here.
   • The Object to bake option indicates which Objects should be considered for baking. By default, all Objects with non-empty mapping will get baked at once. For example, there could be mapping on the Armature with the basic animation. Additionally, there could be mapping on the mesh with some corrective shape-key Actions. Or it could be useful where there are separate Objects for the tongue and teeth.

2. Review errors/warnings and press the Ok button. Note:

   • The baking might still work even with some errors/warnings.
   • If you are repeating the bake,press the Remove strips button to remove the previously baked Actions and make room for new Strips.

3. After the baking is done, review the baking report. The report is shown only when there were any baking errors/warnings.

1. Open the NLA Editor. You can tweak the position/length/blending of the NLA Strips. Some default Strip properties can be changed in the Strip placement settings section. However, the Bake to NLA would have to be run again (removing the existing Strips first).

2. Hint: In Blender, it is possible to change a property of multiple objects at once. For instance, to enable auto-blending on all strips:

   • Select all the strips in the NLA (press the a key).
   • 2x Shift-click any of the already selected strips again to make it active. This should show the side panel.
   • Alt+click the Auto Blend In/Out to distribute the change to all the selected strips.

If needed, the NLA Tracks can be baked into a single new Action. Note, if you have both a normal-action track pair and a shapekey-action track pair, they have to be baked one-by-one.

1. Select the Armature and go to Pose mode (for normal-action tracks).
2. Select the Bones you want to bake. For example, press a to select all.
3. Select the strips in the NLA track you want to bake. Use the b key and box-select strips if you don't want to include all tracks.
4. Then go to NLA Editor/main menu/Edit/Bake Action.
5. Consider checking the Visual Keying and Clean Curves options:

A new Action will be created and selected in the Action Editor. The two RLPS tracks can now be disabled or removed (mouse-hover on the track name and press x).