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===Solution 1:===
 
===Solution 1:===
  
a) If the color matching functions <math> f_k(\lambda)  </math> has negative values, it will result in negative values in <math> F_k </math>. In this case, the color can not be reproduced
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a) If the color matching functions <math> f_k(\lambda)  </math> has negative values, it will result in negative values in <math> F_k </math>. In this case, the color can not be reproduced by this device.
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b) The CIE color matching functions are not always positive. <math> r_0(\lambda) </math> takes negative values. This is the case because, to match some reference color that is too saturated, colors have to be deducted from the <math> R, G, </math> and <math> B</math> primaries to match the color. This results in negative values in r, g, and b. So the color matching functions at the corresponding wavelength have negative values.

Revision as of 19:51, 10 November 2014


ECE Ph.D. Qualifying Exam in Communication Networks Signal and Image processing (CS)

Question 5, August 2013, Part 2

part1, part 2


Solution 1:

a) If the color matching functions $ f_k(\lambda) $ has negative values, it will result in negative values in $ F_k $. In this case, the color can not be reproduced by this device.

b) The CIE color matching functions are not always positive. $ r_0(\lambda) $ takes negative values. This is the case because, to match some reference color that is too saturated, colors have to be deducted from the $ R, G, $ and $ B $ primaries to match the color. This results in negative values in r, g, and b. So the color matching functions at the corresponding wavelength have negative values.

Alumni Liaison

Ph.D. 2007, working on developing cool imaging technologies for digital cameras, camera phones, and video surveillance cameras.

Buyue Zhang