Digital video recorder (DVR) company TiVo filed lawsuits yesterday against Verizon and AT&T in regard to various aspects of their DVR technology patents. I have long wondered why anyone would bother buying a TiVo when you can get virtually the same service through your cable provider with a DVR box. This partially answers my question: TiVo has patents. And yet, my new Verizon FiOS package has strikingly similar DVR capabilities. Hence, the lawsuit. So I decided to see whether or not I'm convinced that TiVo's patents should hold up in court.*
First, what is TiVo suing about? According to a Financial Times article about the lawsuit:
TiVo argued in its complaints that these services infringed on three of its patents, including ones for a "multimedia time-warping system" and a "system for time-shifting multimedia content streams."
I somehow managed to find the two patents they mention on the U.S. Patent and Trademark Office Website. Let's focus on the latter, because I think we'll probably draw pretty similar conclusions about both. Here's the description of the time-shifting patent, from the USPTO website (if you're interested, here's the other one):
A multimedia time warping system. The TV streams are converted to an Moving Pictures Experts Group (MPEG) formatted stream for internal transfer and manipulation and are parsed and separated it into video and audio components. The components are stored in temporary buffers. Events are recorded that indicate the type of component that has been found, where it is located, and when it occurred. The program logic is notified that an event has occurred and the data is extracted from the buffers. The parser and event buffer decouple the CPU from having to parse the MPEG stream and from the real time nature of the data streams which allows for slower CPU and bus speeds and translate to lower system costs. The video and audio components are stored on a storage device and when the program is requested for display, the video and audio components are extracted from the storage device and reassembled into an MPEG stream which is sent to a decoder. The decoder converts the MPEG stream into TV output signals and delivers the TV output signals to a TV receiver.
I am pretty sure that means that in English this means you can record a TV show and watch it later. But this explains how TiVo does that process, precisely. It sounds easy in English, but this description shows that there's a heap of technology behind it. And that's what TiVo patented -- the process by which they record digital video media.
Now, let's think about what's patentable to see if this idea conforms. It's my understanding that for something to earn a patent, it must pass the following test, conforming to all of these criteria: