PDA

View Full Version : From 3D Scan to Blend Shape Mesh in 1 Hour.


DimensionalImaging
09-06-2010, 05:32 PM
We wanted to share a method that some of the world's top game studios are now using to create ultra-realistic characters for their games. We've put together a real-time video tutorial with commentary that that shows the process end to end, from 3D scan to Blend Shape mesh in just 1 hour.

A quick synopsis (4x speed-up, no audio) of the process can be found on youtube: time-lapse (http://www.youtube.com/watch?v=JM8G1gxMK-0)

The full 1 hour demo with audio can be downloaded for viewing from here: full-demo (http://www.di3d.com/downloads/youtube_materials/di3d_transfer_tools_demo.mov)

An OBJ model of the finished sample head can be downloaded from here: sample-model (http://www.di3d.com/downloads/youtube_materials/wasim_finished.zip)

If you just want an overview of the process, here it is:

Stage 1 - 3D Scan patch alignment:

http://www.di3d.com/downloads/examples/1HourDemo/di3dcapture.jpg


We used our standard facial capture system to capture multiple views of the subject's head. We did this by rotating the subject in front of the capture system. We used DI3Dcapture to process the images and give us a 3D surface for each pair of images.

Stage 2 - 3D Scan Patch Alignment

http://www.di3d.com/downloads/examples/1HourDemo/alignment.jpg


We used a few of DI3Dview's simple alignment and trimming tools to align and trim the seperate 3D surface patches together, so that we ended up with a 360 model of the subject's head. The seperate patches were then combined into a single 3D model of the subject's head.

Stage 3 - Shape Transfer

http://www.di3d.com/downloads/examples/1HourDemo/shape_transfer.jpg


We then used DI3Dview's Shape Transfer tool to retarget a template mesh to the completed 360 head model we created in Stage 2. The shape transfer tool lets you select landmarks to register the 2 models, and then the template mesh is effectively 'shrink wrapped' onto the 360 scan, gving you the shape that you want, but with the mesh topology you want.

This tool operates on predefined mesh groups at different levels, you can choose to fully 'snap' a group, 'warp' a group, or do nothing to a group, this is particulary useful for preserving the topology of an area like the ear for example. Vertex positions can also be tweaked, allowing you to drag the template vertices along the surface of the scan so you can optimise your mesh topology quickly and easily.

Stage 4 - Material Transfer:

http://www.di3d.com/downloads/examples/1HourDemo/material_transfer.jpg


We used DI3Dview's material transfer tool to reproject the original high resolution images captured at the very start of the process onto our retargeted template model. The material transfer tool lets you generate extremely high-resolution texture and normal maps that match up to the model perfectly.

The material transfer tool also lets you correct geometry so that it reprojects to the texture maps with incredible precision. the size of the texture and normal maps can be specified by the user at any resolution, making it incrediblly quick to produce multiple resolution texture and normal maps.

The final model:

http://www.di3d.com/downloads/examples/1HourDemo/wasim_render.jpg


Remember, this process was completed in 1 hour! watch the movie (http://www.di3d.com/downloads/youtube_materials/di3d_transfer_tools_demo.mov) to see exactly how it's done.

Note that we are not artists, we're software developers, so we've put nothing artistic into this at all, it's all just results from a software process, and there is still plenty of room for artistic expression, we like to think we just get you to the artistic stage a lot quicker, leaving more time for artists to do what they like to do and what they want to do.

Also note that this process can be repeated with different expressions to quickly and accurately create a series of Blend Shapes that can be used to generate exteremely realistic animations.

Any questions or comments let us know below and we'd be happy to answer, or contact us at info@di3d.com (http://forums.cgsociety.org/info@di3d.com)

CGTalk Moderation
09-06-2010, 05:32 PM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.