Why do red colours often look so pixelated?

[CoCoNiPs]

I've noticed in both commerical vcd's (mpeg 1 ) and my own encoded DivX videos and elsewhere that often Strong red colours/scenes in videos often seem to be pixelated or show lots of jagged edges.

Is there any reason for this? I have not noticed this phenomena with any other colour

[Trenton_Net]

I have noted this too. Its a very good question, and I would like to figure it out too.

[homerpez]

I think it has something to do with MPEG-1 and MPEG-2 compression (I know that doesn't answer your question, nor mine)...

Should be noted that if you view these "pixelated" red areas on an analog TV, they merely look "sharp", at least that's my experience. Only on a computer monitor does it look strange.

[CoCoNiPs]

Anyone else have any ideas?
Is this question better suited to a diff section? I don't wana repost for no reason

[Douglesh]

yes, it happens with red. And only red. This happens only when i playback VCD's on my monitor, on my TV the jagged edges are smoothened like all other colours. Now to why it happens.

The reason that red appears jagged is because the colour space equation used. YUV 4:2:0 means that you will lose resolution on colours, moreso red. Since VCD cannot be made in 4:2:2, or 4:4:4, there is no solution to this problem.

4:2:0 means that the colour components are divided by four, 4:2:2 means the colour components are halved, 4:4:4 means there is no loss in colour components.

[Douglesh]

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Only on a computer monitor does it look strange.
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Yep.

[CoCoNiPs]

This phenomena is still very noticeable in Divx captured in YUY2 YUV 4:2:2 interleaved (acording to vdub anyhow)
Is this for the same reason?