Hack66.Videoconference from Your Car


Hack 66. Videoconference from Your Car

With mobile broadband Internet connections, car PCs will soon achieve James Bondstyle videoconferencing.

I think it was 1998 when I first started trying to set up a webcam in my car. I have a Nash Ambassador, and in addition to putting a screen in the center console, I hooked up an X10 camera facing the driver, with the eventual goal of letting people keep tabs on me. For several years I tinkered with a number of low-speed, expensive Internet solutions, such as analog cell phones connected to 14.4 modems, while searching in vain for an affordable flat-fee service.

Fast forward several years, and wireless connectivity has matured a lot. GPRS (and more specifically, EDGE) networking has brought the bitrates into ISDN range (64128 kbps), and pitiful but recognizable streaming video has become a viable option for in-car use.

Since two of my cars (my 1950 Nash and my 1998 Malibu) already had X10 cameras in them, I wanted to find out if I could finally realize my dream of a James Bond (or Austin Powers, depending on your pop-culture exposure) in-car videoconferencing experience. This hack will take you through my attempts to get videoconferencing working between my home PC and my car.

6.6.1. Choosing Your Conference Software

The best conference program I've used is the Mac-only iChat. It has a very good codec and smooth full-screen display, and with my Apple iSight FireWire camera, the picture is very clean. AOL recently made their Instant Messenger product (AIM) compatible with iChat, so my first thought was that I could use AIM on my CarBot (which runs Windows XP) and iChat on my Mac in the house. Unfortunately, as I soon found out, iChat had set my expectations too high.

To get video into my CarBot car PC, I decided to use a USB 2.0 video capture device. Since I was using an X10 video camera, which outputs composite video like a TV (instead of an integrated USB webcam), I needed a composite video capture device. I went for the cheapest thing I could find at Fry's Electronics, a $59 USB video capture dongle. For my initial tests I used WiFi networking, which depends on the car being parked near an access point.

Figure 6-9 shows a diagram of a vehicle and the various parts of the videoconferencing setup.

Figure 6-9. Videoconferencing car PC setup


The good news is that my setup worked cleanly and perfectly. The bad news is that AIM's chat program has no full-screen mode. Thus, although my conferencing buddy on the Macintosh in my house was able to see a full-screen image of my face, the AOL chat program only showed me a small-screen image of my partner. This, on an already small 7" touchscreen in the car, was not what I was afterI wanted to be able to have a full-screen video chat with the other party.

Today's instant messaging programs quite reasonably make the assumption that you are going to type a lot and read a lot, both things you should not be doing while driving.


My next step was to check out several other chat programs to see which would give me the video experience I was looking for. I looked at Yahoo! Chat, but their model is more suited to a webcam than a two-way conference. I then tried MSN, but it has the same drawback as AIMyou can't do full-screen chats.

I finally tried out Trillian (http://www.trillian.cc). With perfect timing, they had just come out with Version 3, which supports the videoconferencing protocols of all the major IM apps (AIM, MSN, Yahoo!) and offers full-screen video.

For my testing, my CarBot was using an Orinoco PCMCIA WiFi 802.11b card, installed in a 1-GHz VIA EPIA M2 motherboard, with 256 MB of RAM. One of the things I quickly learned about Trillian is that it takes a lot of CPU power. I'm guessing that's because they've just implemented the codecs for each of the major IM apps, and they're pretty unoptimized at this point. On my desktop 1.6-GHz Athlon it only took 15 seconds or so to start a chat with my 1.5-GHz Apple PowerBook, but it took more than twice as long to negotiate a chat with the CarBot.

6.6.2. Going Wireless

Although the new Verizon EVDO network offers broadband speeds [Hack #62], I had already signed up for an AT&T Wireless EDGE networking phone. I wanted to see how well I could conference with just the 6080 kbps EDGE provides. People video-chat and webcam on modems all the time and get a few frames per second, which I would have been happy with.

I plugged a Bluetooth adapter into my CarBot so that it could get online through my phone, and then I paired the phone and the computer [Hack #63] and set up dial-up networking so that the CarBot would dial up through the phone. I tried repeatedly to get the conferencing going over this connection, but the combination of high latency, low bandwidth, and an underpowered car PC brought Trillian to its kneesI could never establish a connection, and it simply timed out repeatedly. However, when I used the same Bluetooth-to-EDGE connection on my faster desktop PC, I was able to get connected, so the speed of the machine clearly has a lot to do with it. Later, I tried EVDO from Verizon, with similar results.

6.6.3. Not Quite There Yet

My endeavor showed me that while we're right on the cusp of in-car videoconferencing capabilities, it's going to take a little more software and hardware development to pull it off.

One frustration I had with all the IM apps, Trillian included, was that I could not get them to auto-accept chat requests. The Accept button is just big enough for me to hit it on a touchscreen, but I can't really do it when I'm using my non-touchscreen setup. However, I know I can solve that problem with a scripting program [Hack #58], so I'm not overly worried about it.

After playing with various apps, I think Yahoo! Messenger would be a decent way to set up a one-way webcam, where your car uploads a shot of you once a second so that people can see you when you drivethis would work well on even the slower modem-speed connections available with base-level GPRS.

In conclusion, while my PC teleconferencing setup has enough speed to do voice chat and basic webcam delivery, my dreams of full-screen, one- or two-way videoconferencing in the vehicle will have to wait until faster broadband wireless comes about 20 miles north in Los Angeles county to meet me, or until someone writes conferencing software specifically for the car that's optimized for wireless 2.5G (4080 kbps) connections.

One lesson I learned from this attempt is that the current low-power VIA processors popular for in-car computers are just too underpowered for videoconferencing. I've also learned that without custom software development, nothing less than wireless broadband (or WiFi while the car is stationary) is sufficient for conferencing.



    Car PC Hacks
    Car PC Hacks
    ISBN: 0596008716
    EAN: 2147483647
    Year: 2005
    Pages: 131

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