Linux Powers The Spiderwick Chronicles

“We currently have six RaveHD systems at the studio”, says Darling. “They're used to provide dailies in our screening rooms. We also use them for smaller reviews and on-demand playback for artists in special viewing rooms. And whenever we shoot with HD cameras on our stage, we use RaveHD to acquire the images and bring them on-line as individual digital frame files. We have been working with SpectSoft since 2002, before the RaveHD product really existed. RaveHD is an awesome system. It has a really nice design that allows it to integrate perfectly in our dailies pipeline—very reliable and easy to use”. The RaveHD box is a Linux embedded system that plays cinema-grade motion pictures at data rates that would choke a PC.

“I originally met [SpecSoft partners] Jason and Ramona Howard at a Linux Movies meeting in Berkeley, shortly after I joined Tippett Studio”, says Darling. “At that time, we were looking at developing a new dailies system. They had developed a Linux driver for the AJA Kona HD/SD card and had developed some DDR and editing tools. We were able to form a great relationship with SpectSoft where we provided specifications and requirements to them in order to help create a system that suited our purposes.” LinuxMovies.org is an association of Linux motion-picture technologists founded in 2002 [by Robin Rowe, author of this article].

Tippett uses more than 1,200 processors in its renderfarm. “Tippett Studio has its own shading library built around the RenderMan Shading Language. Our pipeline tools are also centered around the RIB interface. The most important consideration for renderfarm configuration is that all jobs submitted the night before must be finished by the next morning”, says Darling. “Each morning we do dailies to review the previous day's work. If the job is not finished, it can't be properly reviewed. There are occasional exceptions for special shots that may run long, but for the most part, we want everything to finish overnight.” The Tippett renderfarm is managed by a proprietary batch-scheduling software, so that each computer in the farm is working on only one frame at a time. “Our distributed rendering system Batch-o-matic has been in use at the studio for ten years”, says Darling.

Figure 6. Tippett Studio's renderfarm is managed by its proprietary Batch-o-matic system. In its GUI interface, CPUs are represented as circles with color-coded indications of their activity level and status. Information about an artist's render jobs is represented by color-coded squares indicating number of CPUs in use, as well as an overall status bar. More detailed information is shown for a specific job, with status for each task and frame.

JET is a proprietary Python-based system comprising software tools and scripts used to implement a visual effects and animation pipeline. “A visual effects and animation pipeline is an assembly line of software used to organize, automate and facilitate the creation of computer-generated imagery”, says Darling. “The JET tool is highly customizable, featuring XML-based user-interface templates that can be modified to suit specific types of artists or production needs. JET uses modular template chunks to perform each of the tasks in the pipeline, such as rendering or compositing. The templates are implemented as Python objects and are centrally located. JET is not only implemented entirely in Python, but it's also used to generate Python scripts automatically. These custom scripts form unique pipelines for each computer graphics job to run on the renderfarm.”

Figure 7. JET is Tippett Studio's proprietary tool for creating jobs that are to be submitted to the renderfarm. Each job comprises a series of chunks (as shown in the panel on the left) that perform specific tasks, such as making a RIB, growing fur, rendering with RenderMan and compositing with Shake. The primary work area on the right provides an interface for the selected chunk.

Tippett Studio uses Apple's Shake compositing software, which has been discontinued. “We took advantage of Apple's offer of selling the Shake source code to us”, says Darling. “We don't plan on modifying it, but it is good to have for an insurance policy. Shake is still very prominent in the visual effects industry. It's useful to be able to share Shake projects with other studios we're collaborating with. Shake has a really nice image-processing engine. In addition to standard compositing, we use it for all kinds of image-processing solutions in our pipeline. The product is very mature and feature-rich. It has support for plugins, which allows us to develop and enhance compositing nodes whenever we need something new. We don't have any current plans to switch compositing packages, but we're always keeping an eye on what's out there.”

“We use Photoshop CS as the painting interface for our texture painting, as well as for matte paintings”, says Darling. “It's used directly on Windows and Mac systems. Our goal is to use a system such as Parallels to permit artists to run tools outside their primary operating system. Deep Paint 3D is used to paint textures for 3-D models. The actual painting is done with Photoshop, but the interaction with the model is done in Deep Paint.” Deep Paint and Photoshop are both non-Linux commercial tools. Some studios, such as DreamWorks Animation, use Wine to run Photoshop on Linux. Another option is to run an open-source Linux paint package that supports industry-standard high-fidelity image formats DPX and OpenEXR (such as CinePaint). However, Deep Paint on Wine is untried, and there's no open-source option.

“When painting in Photoshop, it is essential to be able to view the image with the same type of color management used to produce the final rendered image”, says Darling. “Photoshop supports ICC profiles for color management. Since we use cineSpace in the rest of the pipeline, we had a tool created that would allow us to produce an ICC profile that matched the cineSpace profile. We collaborated with Joseph Goldstone, who is a member of the International Color Consortium (ICC) to create this tool.”