Someone give Video Digital Format people a dictionary

[fluffymark]

Thing I didn't know I found out this afternoon:

The "Industry Standard Square Pixel" has an aspect ratio of exactly 768:767.

*boggle*

WHY???

Comments

[fluffymormegil.livejournal.com]

Because they're on Dopaz.

[fluffymark]

Quite likely, yes. :)

[zotz]

Because it was fitted retrospectively onto an earlier system, according to that page. That's what happens when backwards compatibility is more important than elegance.

[fluffymark]

Sadly that seems to be the case, yes. Nobody seems to mind, anyway. I doubt anyone can spot the difference.

[compilerbitch.livejournal.com]

It's probably a hardware hack for PAL or NTSC, allowing a pixel clock to be used that is an exact harmonic of the colour subcarrier. Without that, if the video DAC's reconstruction filter doesn't have a sharp enough slope, any remnants of the pixel clock would cause quite horrible vertical banding in hue/saturation. It's probably not an issue these days, but 10+ years ago video DACs were pretty crap.

(I worked on digital video hardware many moons ago, sorry for the bizarre braindump) :-)

[fluffymark]

Sounds vaguely correct, as far as I can surmise. And Video DACs are still crap. Capturing video is a real pain.