4:2:0 safe colors

[Zarxrax]

Does anyone know where I could find a pallete showing colors that are safe to use in mpeg-4 encodes? Certain colors tend to bleed, and look blocky.

[Acaila]

What if you did find it. How would you strip a video of a certain color you don't want (because that color will look blocky)???

[Zarxrax]

Im not referring to stripping colors from anything, but merely to know what colors are ok to use for self-created content (graphics, subtitles, etc), as that type of stuff usually exhibits the problem much more frequently than colors encountered in an actual video.

[Acaila]

Well ok.

I believe it's not so much certain colors, but more like high frequencies/intensities of each color and uniform areas of the same color that give a codec a hard time.

[Zarxrax]

Yea, you seem to be right. It seems that practically any sort of red gets blocky though... This confuses me to no end! I'd just like to find some way to know if its going to look like crap BEFORE i encode.

[trbarry]

Are you by any chance talking about this (http://www.hometheaterhifi.com/volume_8_2/dvd-benchmark-special-report-chroma-bug-4-2001.html) effect?

- Tom

[gabest]

I think this is the exact opposite to that problem. The pixel colors are mixing with the surroundings after they are converted and downsampled from rgb to the yuv format that the encoder needs.

[Milkman Dan]

I read just the other day that on spots of Pure color, strengths above 230 should be avoided to prevent bleeding.

Dunno if that helps.