gave the digital artists multiple angles of each performance. A technically challenging scene was near the end of the film when the computer-generated Neytiri held the live action Jake in human form, and attention was given to the details of the shadows and reflected light between them. The lead visual effects company was Weta Digital in Wellington, at one point employing 900 people to work on the film. Because of the huge amount of data which needed to be stored, cataloged and available for everybody involved, even on the other side of the world, a new cloud computing and Digital Asset Management (DAM) system named Gaia was created by Microsoft especially for Avatar, which allowed the crews to keep track of and coordinate all stages in the digital processing. To render Avatar, Weta used a server farm making use of 4,000 Hewlett-Packard servers with 35,000 processor cores with 104 terabytes of RAM and three petabytes of network area storage running Ubuntu Linux, Grid Engine cluster manager, and 2 of the animation software and managers, Pixar's RenderMan and Pixar's Alfred queue management system. The render farm occupies the 193rd to 197th spots in the TOP500 list of the world's most powerful supercomputers. A new texturing and paint software system, called Mari, was developed by The Foundry in cooperation with Weta. Creating the Na'vi characters and the virtual world of Pandora required over a petabyte of digital storage, and each minute of the final footage for Avatar occupies 17.28 gigabytes of storage. It would often take the computer several hours to render a single frame of the film. To help finish preparing the special effects sequences on time, a number of other companies were brought on board, including Industrial Light & Magic, which worked alongside Weta Digital to create the battle sequences. ILM was responsible for the visual effects for many of the film's specialized vehicles and devised a new way to make CGI explosions. Joe Letteri was the film's visual effects general supervisor. Music and soundtrack Composer James Horner scored the film, his third collaboration with Cameron after Aliens and Titanic. Horner recorded parts of the score with a small chorus singing in the alien language Na'vi in . He also worked with Wanda Bryant, an ethnomusicologist, to create a music culture for the alien race. The first scoring sessions were planned to take place in early 2009. During production, Horner