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Converting a Given Color Phase to I and Q

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I'm wondering what the proper formula might be in regards to converting a given color phase angle to the signals I and Q that I could then convert to RGB along with Y' (luminance)?


For example, Medium Green as represented by the Texas Instruments TMS9918A VDP has a luminance value of 0.47 (Y') and a phase angle of 204 (actually 237, but minus 33 degrees). What I want to know is how to obtain I and Q from the 204.


The TMS9118/9128/9129 datasheet does list additional information like A' which refers to the square root of the sum of the squares of E'I and E'Q, both of which represent gamma-corrected I and Q signals, which respectively are the orange-cyan and magenta-green axis signals placed 33 degrees ahead of the E'R and E'Y (orange-cyan) and E'B and E'Y (magenta-green) signals.


Thank you,





Edited by ColecoFan1981
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