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I want to overlay 3d objects on live webcam for my project. I have overlayed 2d objects like googles, mustache, and hat. Now I want to overlay 3d objects like beard, mustache, and hair. I searched over some articles and tutorials, but all of them were ambiguous and didn't teach where to start. From what I have learned I need to create 3d objects using blender and import it using OpenGL and then somehow overlay it to the facial landmarks. I want to know what I need to learn to achieve this objective. I have read the previous question on this source1 and it didn't help much. Also, I have read several blogs like this, this, and the best one here and various others while surfing. I know I am entering into AR/VR, but I ready to learn the things required to get my work done.
There are various libraries/frameworks which don't require to code anything like SparkAR, Virtualtryon, ditto, etc. but they don't teach you anything. I want to learn how to do these things by myself. If I create my 3d object like hair(hair-like Goku in SuperSaiyan)/Mustache or eyes in blender how can I overlay it in real-time on webcam using OpenCV or any other python compatible lib/framework? I mean overlaying 3d hair over my own hair, overlaying 3d eyes over my eyes and similar. What are the things required to do such a task? What things do I need to learn?