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| author | giraffedata <giraffedata@9d0c8265-081b-0410-96cb-a4ca84ce46f8> | 2018-03-13 19:59:28 +0000 |
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| committer | giraffedata <giraffedata@9d0c8265-081b-0410-96cb-a4ca84ce46f8> | 2018-03-13 19:59:28 +0000 |
| commit | 2fbd091ec3feaedbb7e73885f7e82e0b9e4412a5 (patch) | |
| tree | 5e23e14320eb1d61b6877440f69d2cd8cdac2fb7 /lib | |
| parent | 4f77a07461cf525160969f542b58b04d64cc0cab (diff) | |
| download | netpbm-mirror-2fbd091ec3feaedbb7e73885f7e82e0b9e4412a5.tar.gz netpbm-mirror-2fbd091ec3feaedbb7e73885f7e82e0b9e4412a5.tar.xz netpbm-mirror-2fbd091ec3feaedbb7e73885f7e82e0b9e4412a5.zip | |
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git-svn-id: http://svn.code.sf.net/p/netpbm/code/trunk@3171 9d0c8265-081b-0410-96cb-a4ca84ce46f8
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/ppm.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/lib/ppm.h b/lib/ppm.h index 6f1f21b5..7c483b59 100644 --- a/lib/ppm.h +++ b/lib/ppm.h @@ -220,6 +220,10 @@ PPM_DISTANCE(pixel const p1, #define PPM_LUMIN(p) ( PPM_LUMINR * PPM_GETR(p) \ + PPM_LUMING * PPM_GETG(p) \ + PPM_LUMINB * PPM_GETB(p) ) + +/* The coefficients in the following formulae are functions of + PPM_LUMIN{R,G,B} and nothing else. +*/ #define PPM_CHROM_B(p) ( -0.168736 * PPM_GETR(p) \ - 0.331264 * PPM_GETG(p) \ + 0.5 * PPM_GETB(p) ) |