QTube diagram courtesy Quantel


Quantel came to NAB this year with the cloud on its mind. Touting “global teamworking,” the company was positioning its new QTube system for accessing and editing footage over IP connections as a revolutionary new tool. Quantel Marketing Director Steve Owen invoked the cell phone, opining that QTube could transform broadcast workflows as surely as mobile phones streamlined telecommunication. “QTube means you’re never out of touch with your content,” he said.

Basically, QTube connects a Quantel Enterprise sQ production system for news and sports broadcast to the world outside through something called the QTube Transformer – a combination of file virtualization and web streaming. A full-on QTube implementation mixes off-the-shelf technology (for example, Microsoft’s SNB2, Silverlight, and IIS Smooth Streaming) with proprietary Quantel tools, including the Quantel Virtual Filing System or QVFS, a special file abstraction layer that makes footage accessible to the outside world, and something called FrameMagic, a media-management protocol that helps reduce the burden of transferring huge media files across the Internet.

The QTube system sees media as myriad individual files, each representing a video frame or audio samples. Each frame of video is uniquely referenced, and the system keeps painstaking track of which frames have been changed by editing operations in order to reflect an editor’s work without actually transferring more frames than nexessary. When an operation like a transition or color-correction is applied, new “delta” frames are created in the system. The QVFS generates an efficient XML manifest that denotes which frames make up a logical clip, and can be shuttled easily between client and server.

This system also allows new, live recordings to be edited together with preloaded content. The system initially represents the incoming footage as blank frames, then gradually incorporates the video and audio data as it’s uploaded. New footage can be shot in the field and edited into content that lives on a server, but when the new clips are published as AAF files, only the necessary frames from the local footage are actually transfered.

Files stored in the QTube system can be accessed in a number of ways. A simple QTube browser based on Silverlight allows users to view clips, add notes, and edit metadata. (Media can be reviewed just 30 seconds after it’s captured live.) QTube Edit is a Windows 7 application that enables frame-accurate editing over the Internet using the same interface as sQ Cut, one of Quantel’s ENG editing tools. And the QTube OpenAPI will allow third-party platforms to work with QTube, given a little development work.

QTube is currently aimed squarely at broadcast news and sports operations, but there’s no reason to think a similar system geared toward post-production isn’t in the cards. The first generation of QTube technology is already in beta, has been demoed to 300 potential customers this year, and is slated to ship in May.