Hello Nathalie Froissart
Thanks for reaching out to us, and sorry there is no video for how to connect a 3d character with Viseme, there is only a video made to introduce Viseme - https://www.youtube.com/watch?v=ui9XT47uwxs It talks about 3D Viseme from 2:12. Since you mentioned the document, I guess you have viewed this video already - https://learn.microsoft.com/en-us/azure/cognitive-services/speech-service/how-to-speech-synthesis-viseme?tabs=3dblendshapes&pivots=programming-language-csharp#3d-blend-shapes-animation
In one sentence, the Azure Text to Speech Visemes features help you to get the voice and Blend Shapes JSON for the visemes timeline, you need to use the result to drive character animation. You can build your own characters and automatically animate them.
Besides the video and document you have mentioned, the character in the sample is from Mixamo - https://www.mixamo.com/#/
For the 3D Visemes, the most important thing is blend shapes event, you can use blend shapes to drive the facial movements of a 3D character that you designed when you get the viseme output.
The blend shapes JSON string is represented as a 2-dimensional matrix. Each row represents a frame. Each frame (in 60 FPS) contains an array of 55 facial positions, this is how - https://learn.microsoft.com/en-us/azure/cognitive-services/speech-service/how-to-speech-synthesis-viseme?tabs=3dblendshapes&pivots=programming-language-csharp#get-viseme-events-with-the-speech-sdk
More information about Azure Viseme - https://learn.microsoft.com/en-us/azure/cognitive-services/speech-service/speech-synthesis-markup-structure#viseme-element
Though is no entire sample for how to do so, I have found a external example you may want to refer to - https://www.linkedin.com/pulse/azure-lip-sync-3d-model-animation-curtesy-amazon-peter-laker?trk=pulse-article_more-articles_related-content-card The author built the animation with vary cloud services include Azure.
This is the Github Repo - https://github.com/ProjectPete/amazon-sumerian-hosts/blob/mainline/examples/three-azure-v2.html
Sorry for the lacking of document, I hope those information helps. Please let me know if you need more information on any point, we are happy to help to get more information from product team side.
Regards,
Yutong
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