A Picture used to be worth a thousand words - before computers. Nowadays, a thousand words will fit comfortably in 6K of storage, while a digitised photograph for use in a newspaper or magazine can take up to 600K. That was the issue for James Meehan, a partner in the leading sports photography agency Inpho three years ago. He needed to archive up to 15,000 images a year on a system that provided total reliability. "Scanning is the next most labour-intensive part of the process after taking the picture," he says. Photographs are shot on film and then scanned for electronic distribution to clients in Ireland and abroad over modem, ISDN and Internet links. Keeping pictures in an electronic archive would mean that the original negative would never have to be scanned again and in time clients could be allowed to browse the archive themselves
Inpho investigated a range of commercial photo archives, with prices of £80,000 and up for the hardware and software. "The only close to satisfactory systems were very costly," says Meehan. Cost was not the most important consideration, however. Since Inpho specialises in sports photography it has huge deadline pressures on Saturdays and Sundays, when it can send out up to 400 pictures in the space of three hours as major sports events finish. Absolute reliability was required.
Normal business support contracts - four-hour response, one-hour response - do not cover this sort of situation. How about 10-minute response times, all weekend, all year round? The only answer was to duplicate the key system components so that they could be swapped in case of failure.
The communications requirement, plus the need to work with Macintosh and PC clients in-house, and an interest in developing Internet links, meant that some form of Unix was a natural choice. But keeping a spare server becomes an expensive proposition with a commercial Unix such as Solaris and its matching Sun servers. Enter Linux. James Meehan had been discussing Inpho's requirements with Niall O Broin, who suggested putting the archive on a high-capacity Web server. Linux could do this, as well as working as a file-server for the company's Macintosh and IBM-compatible computers.
The archive is now stored on a 16GB RAID disk array, fronted by a 166-MHz Pentium server running Red Hat Linux 5.0. Photographs are scanned in on Macintosh clients running Adobe Photoshop and the title, caption, sport, date and other fields required for the archive are added at scan-time. A Perl applet on the desktop simultaneously dispatches the picture to the client who has ordered it and to the archive.
To search the archive, a browser is used to query the Apache Web server running on the file server. Perl-based forms prompt the user for information to search under and translate the search form contents into SQL queries for the MySQL database on the fileserver, which retrieves matching pictures from the disk array.
James Meehan says that this system cost "less than half" the starting price of a commercial alternative. At the same time, it provides reliability by making it affordable to have an identical spare server on standby. There is another significant benefit of the Linux solution: customisation. The archive system has evolved over the last two years, with extra features added as the need for them arose.
Inpho is not alone in relying on Linux. Armagh Observatory (star.arm.ac.uk) has been using Linux for five years. It is now the main operating system there. Of over 40 computers in use, more than two-thirds are running Linux.
Scott Manley, a post-grad student at the observatory, says "we currently have plans to build a supercomputer cluster by connecting several Linux machines together to simulate stellar atmospheres. If we were to buy a single dedicated computer for this task it would cost us 10 times as much."
In Drogheda, St Oliver's Community College (www.socc.ie) has put Linux at the heart of its recently revamped network, offering email, Web access and fileserver facilities to students. Brian Lennon of St Oliver's says they chose Linux "primarily because we needed an operating system that would facilitate batch creation of almost 1200 LAN and email accounts . . . serve the needs of Win 95 workstations (and) do so reliably, quickly and economically."
He says the choice of Linux has been "absolutely" vindicated by their experience. Reliability and consistency are major benefits and "we have not encountered any bugs or crashes so far. Commands do what they claim to do even if some of them take a little getting used to."
At the Internet service provider MediaNet (www.medianet.ie) Webmaster Alex Bacik says Linux is the workhorse operating system for his company. He also points out that MediaNet specialises in connecting home Linux users to the Net.
Gradient Solutions (www.gradient.ie) operates a major intranet/internet project for the international travel business using Linux. Gradient's technology director, Stuart Coulson, says "we have been very pleased (as have our customers) with its performance to date, and that of other freeware such as Apache and QMail. A large travel agent has even asked us to look at how to migrate a service we offer from a Windows NT base to a Linux one for resiliency and performance reasons."
The last word on reliability goes to James Meehan. "It is rock solid . . . it has never gone down except for things that we've done. It has never crashed itself." As he spoke, the server had been running for 55 days continuously since the last time it had been taken down to have some work done on it.
Computimes coverage of Linux will continue with occasional articles in the future.
Fiachra O Marcaigh: fomarcaigh@irish-times.ie