Convert between xyY (where each channel is a floating poing value) and the LogLuv 32bit pixel format.
LogLuv is a pixel format consisting of a 1 bit sign, 15 bits of log2 encoded luminance, and two 8 bit chromanance channels (u* and v* from
CIE L*u*v*.) This encoding was first used in the TIFF file format for the storage of high dynamic range image data in a compact form.
The name LogLuv is something of a misnomer since the
L doesn't refer to the L* in
CIEL*u*v* but rather is the scene-referred illuminance (the Y in
CIE XYZ) that is logarithmically encoded. For clarity, the name should probably be
LogYuv though I am sure Greg Ward had good reasons for chosing to name it as he did.
npm install logluv-encoding
var logLuvEncoding = ;
var logLuvEncoding = ;var xyYColor = 03 05 109;var logLuvColor = logLuvEncoding;logLuvColor; //=> [ 58, 219, 67, 114 ]logLuvEncoding; //=> [ 0.299.., 0.499.., 10.907.. ]//- Notice that the decoded values are very close but NOT exactly the original values//- This is a natural limitation of trying to store 24 bytes of data in just 4 bytes
- v0.5.0 Initial public release
License - MIT
Copyright (C) 2013 Jon-Carlos Rivera
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