To Premult or not to Premult

Now, I've known that 3D elements rendered out of Maya need to unpremultiplied before compositing, but I still wasn't sure when exactly I needed to do it.

I stumbled onto a document at work today that explains the rule:

1. Unpremult before any color correction, and pre-mult after
   
2. There's no need to unpremult before filtering options like blur because these operations should affect the alpha channel
   

Example:

Without un-premultiplying:

With: 

It's subtle, but the white 1-pixel halo around the green character's arm is gone. 

Score 3rd draft

New hat cue:

Score 2nd Draft

Intro v2 (with strings):

Intro v2 (without strings):

Hat Sequence:

Ending v2 (tweaked beginning, and also continues all the way through the credits):

*********************

My thoughts:

• The new intro I think matches the mood of my film better, but at the same time, I kind of like the music in the old one better. However, the flute sounds much better in the new one.
  
• I didn't really like the hat cue at all, it seems too flourishy and ornamental. I think something a lot simpler might work better. I'm not sure if I even need music in this section.
  
• For the ending cue, I like the part when  the credits start playing, but I'm wondering if the tabla beat is too upbeat. The other instruments sound great to me, including the harp that he worked in.
  

Score 1st Draft

My composer is Ludwig Goransson, a graduate of USC's Scoring for Motion Pictures and Television (SMPTV) program. He's worked on the following cues so far:

Beginning:

End:

I had some notes for him, but I think it's a strong start and I'm excited about the rest of the score.

Animation Pipeline

Here's an overview of the process I've used to animate most shots in my film. After much trial and error, I came up with a hybrid approach that combines keyframe animation, motion capture and crowd simulation.

Step 1: 'Hero' characters - keyframed by hand in Maya



Step 2: Add in background crowd (authored in Massive, then imported into Maya using a custom script)

Step 3: Add in middleground crowd (authored in Massive, then imported into Maya using a custom script) *

Step 4: Add in foreground crowd (motion-captured and solved using Vicon IQ and Motion Builder, then imported into Maya)

Final Shot:

* In my pipeline, the middleground crowd could be either Massive or custom mocap. The tighter the shot, the more I used mocap characters that were placed individually in the scene (which takes ages)

Details:

Three layers of crowd (Foreground, Middleground, Background) seemed to be the most effective at creating believable scenes with depth. I also had to spend tons of time randomizing models, shaders and movement so that the crowd was convincing. Check out this test and this other test to see my earlier attempts.

Crowd simulations generated out of Massive seemed to work best for background characters. The problem with building an entire scene with Massive was that it 'felt' like a simulation (no doubt due to my own inexperience with the software). As a result, I resorted to individually placed motion-captured characters for the foreground and middleground crowd layers which really helped break up the crowd motion.

The other advantage of using custom characters in the FG and MG was that I could art direct the crowd and ensure that the crowd parted at just the right time or that the crowd characters helped direct the viewer's eye to the action.

Although all the keyframes were created in different software, Maya became my central application to combine all the animation elements. This approach deviates from the standard industry practice of rendering crowds straight out of Massive using PRMan, but numerous technical challenges (unavailability of RenderMan Pro Server/PRMan at my school, problems importing Maya cameras into Massive, etc) necessitated changes to my workflow. Therefore, I hacked together a MEL script that imported characters from Massive into Maya, and then rendered everything out with RenderMan for Maya. It wasn't pretty, but it worked.

My, What Long Arms You Have!

As I get closer to finishing, I cheat more and more. In this case, I wanted to exaggerate perspective and scale, and had to stretch out Sam's arm to make the shot work.

View from Shot Cam:

View from a different angle:

Topi featured in 'Introducing Maya 2009'

A couple of stills from 'Topi' have been included in Dariush Derakhshani's new book, 'Introducing Maya 2009'.

The still of Bir in the book is actually an early version. The final composite looks more like this:

Needless to say, I'm super-stoked that the images were published.