2011/6/28 Hans van der Meer <h.vanderm...@uva.nl> > I would be pleased to get some advice from "color-knowledgeable people" on > the following matter. > > In TV-broadcasts there are usually two kinds of subtitles present: Teletext > as characters and DVB as pixels. These can be extracted and rendered with > Metapost. I have done this, but I am not very satisfied with the colors > produced. On the television screen they look bright, when rendered in > Metapost they are dull and muddy. The text is barely readable. > > As I am fairly sure I did extract the correct bits from the CLUT contained > in the stream, I wonder if I am doing something not right at the Metapost > side. In the datastream the values given are the most significant 6, 4, 4 > and 2 bits of respectively Y, Cr, Cb, T. These are scaled to the values > given to Metapost by dividing them by 255. > > In the zip one finds the program (ConTeXt MKIV) used for typesetting, an > example pixel map with clut, and the output. I would be obliged to get some > comments. > > > have you already seen http://en.wikipedia.org/wiki/YCbCr ? -- luigi
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