By Karen Moltenbrey
In a new "Go Tagless" TV ad campaign to promote the Hanes Tagless Undershirt, action star Jackie Chan becomes so irritated by his itchy T-shirt tag that he performs daring acrobatic feats in an effort to scratch the offending area.
In the commercial, which is now airing, Chan is shown fighting with an animated tag on the back of his shirt. In an attempt to escape from the persistent rubbing, Chan runs up a pole and becomes suspended in midair.
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| Images courtesy Hydraulx. |
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| When the action freezes, the actor is replaced by a digital double, as the camera sweeps around him in a 360-degree circle. |
"It's a visually unique spot," says Eliza Randall, executive producer at Hydraulx in Santa Monica, California, and a member of the supervision team on set. "The use of digital effects to advertise a product is certainly a departure for a manufacturer like Hanes." The spot's concept, which promotes the idea that tagless is better, was conceived by the Martin Agency in Richmond, Virginia. The agency contracted Hydraulx, which worked with director Matthew Rolston of HSI Productions/Venus Entertainment, to generate the visual effects.
The team filmed Chan with three cameras positioned at three points of an arc around a stage, simultaneously shooting Chan's performance from all three angles. In the final spot he runs up a pole, and the action freezes except for his arm, which continues scratching and battling the pesky tag. Hydraulx employed multiple camera positions to produce a 3D move around the actor's body in a Matrix-like style.
With the use of Maya from Alias Systems, the group generated a CG version of Chan from a combination of motion footage, stills, and a 3D scan the team performed on set. The sequence is live action until the movement freezes. Then, the scene transitions from the live Jackie Chan to his 3D stand-in during the course of the camera move, which ends close to his head and hand as he fights with the tag. In the subsequent shot, Chan reverts to real time, flips off the pole, and lands back on his feet.
To generate the CG stunt double, the group digitized the actor using a Polhemus FastScan scanner to acquire 3D information for Chan's face and upper torso. Using the headus CySlice tool, the group generated a 3D model from the data, and imported it into Maya, where the artists modeled the rest of his body, using photographs taken on set as a reference. The artists then applied photographic textures to the synthetic Chan within Maya. Using 2d3's boujou, the group tracked the live action, and matched the live camera angles to the virtual cameras.
After the shoot, the agency decided it wanted to use a different take for Chan's facial animation at the end of the sequence, requiring the group to merge live-action head footage with the selected live-action body. "We accomplished this by importing and exporting elements between Maya and [Discreet's] inferno, and mapping the live-action alternate facial take onto the 3D head to create visual continuity that made it look real, rather than like a morph," says Louis Mackall, digital effects artist.
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| The 3D monochromatic backgrounds contain a subtle hint of dimensionality, with Chan as the main focus. |
The monochromatic backgrounds are 3D as well. Though they project minor dimensionality, when you see Chan in the fly-around, the depth of the room is apparent but subtle. "We wanted all the dimension on Chan," says Mackall.
The 2D compositing and rendering were accomplished in Discreet's flame and inferno running on SGI Onyx2s and Octanes, whereas the 3D rendering was completed in Maya.
The team also digitally enhanced Chan's famous flip, making his landing appear more solid than it actually was. "He was on wires [to enable him to walk up the pole], so the end result wasn't very graceful," says Mackall. "In fact, we had to do a lot of digital tweaks to make the commercial look right, and none of this work is evident. It's a big effects spot, but it is deceivingly simplistic looking."
Karen Moltenbrey is a senior technical editor at Computer Graphics World.
2d3 www.2d3.com
Alias Systems www.alias.com
Discreet www.discreet.coM
Polhemus www.polhemus.com