Nine Inch Nails "Ghosts 8"
by Shawn Faherty
This video was originally created for the Nine Inch Nails Ghosts Video Contest on You Tube. All 36 instrumental tracks on the Ghosts album are self titled numerically giving artists a clean visual slates to work with minus any symbols or conceptions that may sway creativity. I chose track 8 since I had a similar idea brewing in my head for some time (track 12 and 27 where my other choices).
The main theme to my video was to create a connection of visual energy to the character. Making a helmet to mask the face eliminated facial expression to help the viewer stay focussed on movement and audio changes; or as I like to call it: Visual Music. The goal is to help the viewer hear parts of the song that they might not normally recognize during their first listen.
I began with a storyboard that got me half way through the track. The rest was brainstormed on the fly during software creation. One important step was to film slower than the original track time code. This meant slowing the song down by 50% during green screen filming (studio and crew: www.glitchcrew.com). This gave the character ample time to reach key positions during the music. This slowing of the time also helps when keying out the background since there are more frames, and when sped back up, the movement is given a slight jumpiness and less life like appearance. Frames where brought into Houdini, adjusted for brightness, contrast, color, and special Edge, Fog, and Over composite operators.
The technique of taking a frame, bringing it into Houdini, copying boxes based on color, and creating multiples of these was learned from Garman Herigstad's Houdini 101 learning dvd (www.thegnomonworkshop.com). Some key lessons are extensive use of the Point Sop where I can look up each point's attributes in a Spreadsheet while I'm working. This helps me recognize movement when they are transformed individually based on their color values. Even though my computer is somewhat fast, a Render Output Driver node let's save geometry sequences for faster work-flow. I read them back in with a File node so I could continue creating my network with realistic playback speeds.
Peter Claes' Houdini Technical Effects dvd (www.3dbuzz.com) helped me understand creating complex trails. One trail seemed easy, but try creating multitudes would take for ever if it wasn't for the For Each SOP which let me loop through each trail. Building these systems procedurally gave me the creative power to easily change the number or trails, direction, width, color and so forth without having to recreate them. This is mostly done at a point or primitive level where I can classify attributes, groups, add values or mathematically promote new ones based on arguments. What seems like a lot of scripting is merely an understanding of how Houdini's variables and functions help channel information through the stream of node building.
Finally, there were some hurdles I still needed to figure a way around. Because my character is essentially flat, even in 3D, I wanted some depth from the waves being swung from the guitar. After my camera movements where finalized I key-frame a bone that was attached to the guitar. The bone, with color trails attached, swings out toward the camera giving the illusion that the guitar is in fact doing the same. Also, particles that fly away from the character needed an arbitrary direction to fly to or from, so points in space where created for that purpose with special attention to object normal and world space.
I can't thank SideFx (www.sidefx.com), Peter, Garman and the entire Houdini community enough for helping me along he way. I recently read a tutorial for another 3D program that creates a similar technique and I couldn't believe how many steps it took, especially scripting. I hope anyone looking to get into 3D takes a serious look at Houdini's work flow. Take advantage of Houdini's Apprentice HD and you'll see what I'm talking about!