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Tuesday, May 3, 2011

I'm Seeing Yellow

I’m seeing yellow.  No, really.  Finally.

I’m talking television.  Since 1953 we’ve been watching color television in NTSC and its compromised chroma modulation.  Yellow suffered tremendously – the combination of chrominance and luminance on a bright yellow object would lead to overmodulation…so that whole sextant of the chroma topography was compromised, usually sent toward the darker shades.  Nearly as bad, differential phase problems are most easily seen in the yellow areas.

Enter ATSC.  The yellows are just another bunch of numbers as is any other color.  And they get equal treatment.  So the likelihood of yellow being yellow is a LOT greater.  Of course, magenta (and all her sisters) is better, too, but that yellow thing really makes a difference.  At least one manufacturer is bragging about better yellow through the addition of yellow LED’s but in reality, it’s the modulation scheme that makes the real difference.

So – all those better yellows.  Now turn your attention to compression – not ATSC but the compression being applied to video signals over cable and DTH satellite.  Well, so much for yellow…and red, blue, and green and all their buddies, too.  Bit reduction and other compression along with conversion (in some cases) to QAM took that wonderful yellow away.  Well actually it didn’t – it took away the range of yellows; packed them all into one convenient “yellow.”  Same with the rest of the spectrum. 

Wondering why faces look “cartoony” and the color gradation seems inconsistent at best?  Put an ATSC over-the-air signal next to your cable or satellite version.  Check it out.

The solution?  Less compression, of course but is that going to happen?   Doubtful given the channel proliferation and competition between cable and satellite suppliers.  It points to other access methods that might allow download of the full digitized signal, maybe beyond ATSC.  Hint:  web services like Hulu and others.  If these services provide full bandwidth digitized signals, as Americans see the difference, they will gravitate toward the better service.  After all, with one-to-one delivery, number of channels is meaningless.

The only issue that affects the full bandwidth delivery will be the decision of ISP’s and alternate suppliers to move from “all you can eat” to metered bandwidth charges.  In that case, maybe that beautiful range of yellows isn’t worth it after all.