IP: this is fascinating -- a real life experiment about nutty standards for DTV & PCs -- a test by Alan Reekie

[Dave Farber <farber () cis upenn edu>]

> Date: Tue, 29 Feb 2000 11:05:11 -0500
> To: farber () cis upenn edu (David Farber)
> From: "Richard J. Solomon" <rsolomon () dsl cis upenn edu
>
>
> One of the subjects of great debate in the context of digital TV
> broadcasting standards a few years ago was how to deal with the fact
> that the existing digital video scanning standards for 525 and 625-line
> TV signals did not map directly onto those for images generated by
> personal computers and displayed on picture monitors. As it appeared
> that the debate could not be resolved without at least one side abandoning
> its long-established practice, it the USA the FCC finally agreed that
> digital TV broadcast signals in the USA could use any of 18 different
> scanning standards, including several members of both the digital video
> and computer graphics families. In Europe, however, a consensus was
> reached earlier within the DVB Project that - at least initially - all
> digital TV broadcasts should adopt the existing 625-line digital video
> scanning parameter values: 720 pixels horizontally and 576 vertically.
>
> I was very curious therefore to see how this 'problem' has been resolved
> in practice by the makers of "PCTV" adapter cards, that enable (analogue)
> TV broadcasts to be received and displayed on personal computer screens.
> So last Saturday I bought such a card: Pinnacle Systems's "Studio PC Rave"
> made in Germany (but using a PAL/NTSC/SECAM LSI chip made in Korea) 
> costing only
> 75 Eur (including VAT) which includes teletext and video editing 
> facilities and
> occupies 1 PCI slot in a IBM-compatible PC with *at least*:
> - A Pentium processor at 133 Mhz
> - 32 Mbyte RAM
> - a directly addressable graphics board with Direct-X v.6 software
> - Windows 95 or '98 operating system
>
> Despite a minor installation problem (at first the card did not fit
> fully into the slot, and the manual on the CD-ROM which contained all
> the software failed to explain how to connect up the sound cable, so I
> had to visit the FAQs on the Web site: www.pinnaclesys.com), I soon had it
> operating with nearly all the 40 channels supplied by the local Coditel
> cable TV network. Even those in the hyperband were available, but CNN and
> TVE-International, which are in channels just below the FM Radio band,
> were missing.
>
> Anyway, I was very impressed by the high picture quality on the 15-inch
> high-res PC display screen (set as usual to 800x600 pixels), which seemed
> to be significantly better than on my TV set. At normal 'computer' viewing
> distance there was no visible 'scanning line' effect, nor flicker, and the
> familiar artefacts like 'ringing' or moiré were minimal.
> More specifically, there was no significant difference in quality between
> the 'full screen' picture and that at exactly 728 x 576 pixels, which
> leaves a small margin for the Windows status bar at the bottom. So it seems
> that - once more - what seemed like an important technical issue in the
> choice of standards is not such a big deal in practice...
>
> Incidentally, one advantage of the incorporated teletext decoder is that
> the whole broadcast database is automatically stored in the computer's
> RAM, so after a few minutes you can call up ANY teletext page instantly.
> And you can easily capture screen shots in both TV and teletext mode,
> either as bitmap images (these files are about 10 times bigger than the
> equivalent *.jpg files) or, in the case of teletext, as text files.
> Please contact me it you want further details.
>
> Here are a couple of quarter-size images captured from BBC TV News and
> converted to *.jpg format (click on the icons to display them): {picture 
> removed

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> -- Alan Reekie