Re: Color bars?

[Bill Davis] "Personally I'm not sure what traditional bars mean in a digital world where every color values are typically represented by unchanging numeric data."

What color is the numeric value (178, 234, 72)?

Well, is the color space RGB? sRGB? Adobe RGB? YUV? YCrCb?

Is it Linear? Log? Gamma 2.2? Gamma 1.8?

You can take a video tape, put it in 10 different decks, and within a very tight tolerance, get the same signal coming out of all 10. Try playing a video file in 10 different software, and see what you get.

Without special workarounds, an H.264 made by QuickTime on a Mac will play with the wrong gamma in QuickTime for Windows... and that problem has been around for YEARS. Last I checked even the movie trailers on Apple.com play with the wrong gamma in Windows.

You could argue that Bars & Tone is an old-fashioned way of accomplishing the goal of consistency, but its one that a lot of people are familiar with using. There are some standards for file-based exchange of color space info, but I haven't seen anything reliably used across multiple vendors yet.