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{ RCSid $Id$ } |
| 2 |
{ |
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Peerless' brightness mapping function |
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|
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Mapping of Luminance to Brightness for CRT display. |
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Hand this file to pcomb(1) with the -f option. |
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The picture file should have been run previously through |
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the automatic exposure procedure of pfilt(1), and |
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pcomb should also be given -o option. Like so: |
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|
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pfilt input.pic | pcomb -f peerless.cal -o - > output.pic |
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|
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} |
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La_w : 0.5/le(1) * WE; |
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Lmax_v : 120; |
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La_v : Lmax_v/2; |
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b(La) : .338*La^.034; |
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k(La) : -1.5*log10(La) + 6.1; |
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B_w(L) : k(La_w) * L^b(La_w); |
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L_w(B) : (B/k(La_w))^(1/b(La_w)); |
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B_v(L) : k(La_v) * L^b(La_v); |
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L_v(B) : (B/k(La_v))^(1/b(La_v)); |
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Bmax_w : B_w(3*La_w); |
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Bmax_v : B_v(Lmax_v); |
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|
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lum_w = li(1)*WE; |
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|
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lum_v = L_v(Bmax_v/Bmax_w*B_w(lum_w)); |
| 29 |
|
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mult = WE/Lmax_v*lum_v/lum_w; |
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|
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ro = mult*ri(1); |
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go = mult*gi(1); |
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bo = mult*bi(1); |
