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R3DS Wrap4D – generate topology from animated textures
R3DS Wrap4D is an extended version of Wrap designed specifically for 4D processing. It takes a sequence of textured 3D scans as an input and produces a sequence of meshes with a consistent topology as an output.
The solution includes 12 new nodes. At the heart of the pipeline is the FacialWrapping node which combines the power of the BlendWrapping node with the results from the lip and eyelid detector. The idea behind the node is to provide a robust result that doesn’t require cleanup.
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How ‘Dune’ VFX supervisor Paul Lambert invented the Nuke’s Image Based Keyer
So, what is the IBK keyer? The very non-technical answer to that is that the ‘image- based keyer’ is a proprietary keyer in Nuke that typically deals with classic bluescreen or greenscreen plates (that need keying) by recognizing that these plates do not always have uniform color coverage. We’ve all seen uneven blue and greenscreens; that’s one place where the IBK Keyer can come in handy.
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Capturing textures albedo
Building a Portable PBR Texture Scanner by Stephane Lb
http://rtgfx.com/pbr-texture-scanner/
How To Split Specular And Diffuse In Real Images, by John Hable
http://filmicworlds.com/blog/how-to-split-specular-and-diffuse-in-real-images/Capturing albedo using a Spectralon
https://www.activision.com/cdn/research/Real_World_Measurements_for_Call_of_Duty_Advanced_Warfare.pdfReal_World_Measurements_for_Call_of_Duty_Advanced_Warfare.pdf
Spectralon is a teflon-based pressed powderthat comes closest to being a pure Lambertian diffuse material that reflects 100% of all light. If we take an HDR photograph of the Spectralon alongside the material to be measured, we can derive thediffuse albedo of that material.
The process to capture diffuse reflectance is very similar to the one outlined by Hable.
1. We put a linear polarizing filter in front of the camera lens and a second linear polarizing filterin front of a modeling light or a flash such that the two filters are oriented perpendicular to eachother, i.e. cross polarized.
2. We place Spectralon close to and parallel with the material we are capturing and take brack-eted shots of the setup7. Typically, we’ll take nine photographs, from -4EV to +4EV in 1EVincrements.
3. We convert the bracketed shots to a linear HDR image. We found that many HDR packagesdo not produce an HDR image in which the pixel values are linear. PTGui is an example of apackage which does generate a linear HDR image. At this point, because of the cross polarization,the image is one of surface diffuse response.
4. We open the file in Photoshop and normalize the image by color picking the Spectralon, filling anew layer with that color and setting that layer to “Divide”. This sets the Spectralon to 1 in theimage. All other color values are relative to this so we can consider them as diffuse albedo.
