Beyond The Cell -- Journalists' Video Phone

dimitri_k writes: "This article from poynter.org gives some information about the video phone that has become standard in reporting recently. It uses H.263 for compression, and a satellite phone to call into ISDN lines. Maybe people on Slashdot can brainstorm ways to increase the bandwidth of these things in the short term (i.e. cost-ineffective combination of lines) so that the cable news networks can turn the grainy, live, night-vision shots in Afghanistan clear." This setup looks a little chunky, but when you consider the capability to beam video information from anywhere in the world, it's very impressive.

Comments

More bandwidth?

[merlin_jim]

Well, first off, cut out the full duplex operation. Send voice only out to the field, and use the extra bandwidth for more frames. The reporter on the other end rarely needs to see what's happening in the home office, while the whole world would appreciate a clearer picture.

They're using H.263 compression algorithms... some dismal figures (it was made to be used at 10 fps, for instance!) Here's a nice page detailing the standard and some comparisons to MPEGs...

Here's a great page comparing H.263 to MPEG-4... Hmmm... Jurassic Park encoded in High Quality MPEG-4 beat the 64 Kbit/s rate of H.263 by nearly %20... the video phones are, according to the article, 112Kbit/s... Anyone have any clue about using MPEG-4 to do this? Sounds to me like it'd be a much better compression algorithm...

Most of this is done already

[NMerriam]

I can tell most of the folks commenting on this thread have not used high bandwidth sat phones or done much live video (or both).

The InMarSat system is a geostationary constellation, and requires a pretty decent amount of power to transmit.

It requires a directional antenna, which is part of the reason the phones are as large as they are. The smallest are the size of a small briefcase, and these videophones are not much larger than that.

You can mux together multiple dishes to get 64k, 128k, 192k, 256k, etc, but each 64k requires another dish, another power supply, and more space.

Yes, the codecs are less than perfect, but they are standard, and allow you to connect virtually anywhere in real-time.

We've experimented with live encoding into more efficient formats and quite frankly you don't get much better quality, and the lack of built-in videoconferencing smarts on the part of the codecs costs as much as you gain in efficiency.

Yes, if you can record, encode and transmit in near-real time the quality could be better, but then you're talking about a much more technically complicated setup that a reporter with limited resources has to manage.

Operating a computer in your office is much simpler than doing it on a frozen rock with bombs falling nearby and a poor power supply. If you have a connection, you transmit because you never know when it may go down or your power will die. Getting a few extra FPS for extra time sounds nice in theory, but getting the story out ASAP is more important because 30 seconds from now things could change.

The videophones are an amazing package, and little can be done to improve them much more than the simple march of technology. They'll get smaller, we'll get better sat systems with more bandwidth, the codecs will improve, but for what resources exists now, these things do an AMAZING job of wringing out all the performance possible.