Profile: TiVo

The ultimate in recording television programs, TiVo is a set-top box that does everything for you.

TiVo, Inc., headquartered in Sunnyvale, California, is the creator of the Personal TV Receiver. Michael Ramsay and James Barton founded TiVo in August of 1997. Ramsay and Barton were senior executives at Silicon Graphics, involved with early generation interactive video-on-demand systems.

Personal TV Receiver

The Philips Personal TV (PTV) Receiver is a joint effort between TiVo and Philips Electronics. Philips Electronics manufactures the PowerPC-based hardware, and TiVo designs and develops the software. The appliance uses a modified version of Linux for PowerPC and provides an amazing set of features. It truly is the next generation of VCRs, allowing you to watch what you want, when you want.

TiVo's PTV Receiver does have competition in this emerging market, such as Replay TV. However, the PTV Receiver is currently the only Linux-based system.

You can still do all the things you do with a VCR with the PTV Receiver—except play a VHS tape, of course. However, with DVDs becoming increasing popular, this may not be a significant limitation for you.

TiVo records digitally using MPEG II compression at one of four selectable video qualities. Picture quality at the best setting is as good as the original broadcast, an improvement over VCR technology. Although you can't exchange your recordings with others without copying them from TiVo to a VCR, you won't have to manage a handful of two-hour tapes, either.

Figure 1. TiVo Central

TiVo takes the concept of on-screen programming a step further. Rather than just recording what you schedule, TiVo allows you to rate, with either a thumbs up or down, programs you watch. TiVo will then record shows you've scheduled and shows it finds that match your preferences (see Figures 1 and 2.)

If you happen to watch Friends on Thursday night and give it a thumbs up, TiVo will also record syndicated reruns without being scheduled. What if the TV network switches your program to another night? TiVo will record it automatically at its new time slot, with no programming required. This is made possible by TiVo's built-in program listings, updated nightly by an automated toll-free phone call.

TiVo also enhances your TV watching. TiVo maintains 30 minutes of what's currently being watched, so you can pause, fast-forward or rewind live TV.

For example, if you're watching your favorite NFL team on Sunday, push the instant replay button on TiVo's remote and the action will skip back eight seconds and begin playing. Push the jump button, and you're back to live TV.

If you miss the start of a program, you can watch from the beginning while TiVo records the rest of the show.

Not sure what to watch? TiVo will provide you with recommendations based on your preferences. The interactive on-screen listing means you'll never have to pick up another printed TV guide.

A limitation of the current system is that it is unable to establish individual profiles for each viewer. Instead, TiVo creates a preferences profile for the household as a whole.

Having won a “Best of What's New” award for 1999 from Popular Science, the Personal TV Receiver is getting positive reviews from both audio/video and computer professionals. Ziff-Davis' Equip product reviewer summarized it like this: “TiVo rocks! I've been testing it for a few weeks and can't imagine living without it.”

Figure 2. TiVo Screen

Linux Internals

Source code access, zero cost, high functionality, real-time capability and developer tools were among the factors that prompted TiVo to select Linux. The availability of a PowerPC port of Linux was crucial, since TiVo runs on a PowerPC-based system.

The current system is based on the 2.1.24 kernel. The GNU toolset and Tcl were used to develop all software.

TiVo had to modify the Linux kernel and some open-source tools in order to develop their product. In particular, they added an unbuffered scatter/gather API for disk access, real-time disk scheduling capability, an advanced DMA management subsystem, and support for demand paging and real-time processing. The unbuffered disk access allows the system to handle power outages gracefully. Users won't ever have to worry about waiting for fsck to repair the file system.

The TiVo receiver can update its software automatically. This includes both the TiVo application as well as the Linux kernel that drives the system.

During one of its nightly calls to get TV programming information, it will automatically download and install software updates. No user interaction is required.

A recent upgrade improved the picture quality during fast-forward and improved the algorithm for recommending programs. While certainly not new to PC software (America Online and others have been doing this for years), self-updating software is fairly new to consumer devices.

______________________

Webinar
One Click, Universal Protection: Implementing Centralized Security Policies on Linux Systems

As Linux continues to play an ever increasing role in corporate data centers and institutions, ensuring the integrity and protection of these systems must be a priority. With 60% of the world's websites and an increasing share of organization's mission-critical workloads running on Linux, failing to stop malware and other advanced threats on Linux can increasingly impact an organization's reputation and bottom line.

Learn More

Sponsored by Bit9

Webinar
Linux Backup and Recovery Webinar

Most companies incorporate backup procedures for critical data, which can be restored quickly if a loss occurs. However, fewer companies are prepared for catastrophic system failures, in which they lose all data, the entire operating system, applications, settings, patches and more, reducing their system(s) to “bare metal.” After all, before data can be restored to a system, there must be a system to restore it to.

In this one hour webinar, learn how to enhance your existing backup strategies for better disaster recovery preparedness using Storix System Backup Administrator (SBAdmin), a highly flexible bare-metal recovery solution for UNIX and Linux systems.

Learn More

Sponsored by Storix