Perspective Projection of a 3D head to form a face image

Input: 53490 3D points and for each point (xyz) and color (rgb) of a head

Output: 2D face image as viewed from a particular position / direction

Platform: Matlab

After study, I found the steps to be implemented

• Perspective Projection http://en.wikipedia.org/wiki/3D_projection
• Z-buffering http://en.wikipedia.org/wiki/Z-buffering
• Phong reflection model http://en.wikipedia.org/wiki/Phong_reflection_model

I implemented the above 3 steps in Matlab. But it takes 8 min for the execution. The 2D rendering is part of my project (3D Morphable Models); I will be calling the 2D rendering part 5000 times later. I want the execution time under 1sec.

The bulk (99.9%) of time is taking for z-buffering. The implementation is done following the wiki link.

Can anyone help me to reduce the time in Matlab or suggest other platform? Any tutorials/demo references to understand the above steps will be helpful.

Thanks in advance

[Yuhan Zhang]

I want to work on 3D face reconstruction, but I do not know how to do it. Can you send your code to me to study?

Answer 1

[Jinzheng Sha]

Hi, Chaitanya:

I have seen your question http://www.mathworks.com/matlabcentral/answers/59092-perspective-projection-of-a-3d-head-to-form-a-face-image. I am now working on a project which consists of fitting a 3D facial model to a 2D image. I also get stuck in the persective projection of the 3D model.

I do not understand why do you need z-buffering. Is that because your 3D data includes color? Can I do this task by just multipling the 3D data with a project matrix R?

Hope to hear from you!

Thank you!

[Yuhan Zhang]

I want to work on 3D face reconstruction, but I do not know how to do it. Can you send your code to me to study?

Answer 2

[hagege ruben]

why not simply use the plot3 (or another kind of 3d plot) function while assigning CData to the points and using view to get the point of view that you want? you can then use material and light and tweak some options to get a better rendering