\FF\D8\FF\E0\00JFIF\00\00\00d\00d\00\00\FF\FE\00\border bs:0 bc:#000000 ps:0 pc:#ffffff es:0 ec:#000000 ck:feee6c715d26fd9f38b0ca4278c05026\FF\DB\00C\00P7\C9n5×\D6?\BDê\9Ds\EBp\9F[`8m\B7)o\B5\E8\E6I\99\FE3]]A2\BA\8Cw\D6E\93\\DEv\C8\009\F2\F1NI?uc\\F5\EA\96k\xN<~buv\EA\C8\D7 \8B\84\CEcxI\BBg\AE\9E=\D6+n\EC\80\C8A\8C\AE\EB\CF\D5\DA\E9"2\A4\B9j5\EB\F3W\B63\96\B30Yu\DA\FC8\ED\DF\E7Ms\FB\F1\8E\B3\FA\EA\E8\E6(\883zs\F2_\8DFk\8Bh \00\8C\DCw\D3R\B5+6X\BA\B2\C4j\AB0\B4\FCMw\C2I\8E\9B\E3\A9~9u\FA\D3l\80\C8%p\EE\FDn2€ \00 $\FEj\C4e\A9\DB\~\95\A7\A5\80EK\BB\8DDsP\00@@AD'k\CF\E8\DB\D2(\80\9AK\D3\85\D6lb\F2\BA\8C*\80\00)\95 59\A3R:\F3\CE"\B6\80\88\00\00i1u4ê\E9\F2á\A6\A2\FACM\93WMb*\E0*\00\00\00\00\00(\A8\80\00\00\80\00\00\00\00\00\00\00\00\00\FF\D9 C/// """Conversion functions between RGB and other color systems. This modules provides two functions for each color system ABC: rgb_to_abc(r, g, b) --> a, b, c abc_to_rgb(a, b, c) --> r, g, b All inputs and outputs are triples of floats in the range [0.0...1.0] (with the exception of I and Q, which covers a slightly larger range). Inputs outside the valid range may cause exceptions or invalid outputs. Supported color systems: RGB: Red, Green, Blue components YIQ: Luminance, Chrominance (used by composite video signals) HLS: Hue, Luminance, Saturation HSV: Hue, Saturation, Value """ # References: # http://en.wikipedia.org/wiki/YIQ # http://en.wikipedia.org/wiki/HLS_color_space # http://en.wikipedia.org/wiki/HSV_color_space __all__ = ["rgb_to_yiq","yiq_to_rgb","rgb_to_hls","hls_to_rgb", "rgb_to_hsv","hsv_to_rgb"] # Some floating point constants ONE_THIRD = 1.0/3.0 ONE_SIXTH = 1.0/6.0 TWO_THIRD = 2.0/3.0 # YIQ: used by composite video signals (linear combinations of RGB) # Y: perceived grey level (0.0 == black, 1.0 == white) # I, Q: color components # # There are a great many versions of the constants used in these formulae. # The ones in this library uses constants from the FCC version of NTSC. def rgb_to_yiq(r, g, b): y = 0.30*r + 0.59*g + 0.11*b i = 0.74*(r-y) - 0.27*(b-y) q = 0.48*(r-y) + 0.41*(b-y) return (y, i, q) def yiq_to_rgb(y, i, q): # r = y + (0.27*q + 0.41*i) / (0.74*0.41 + 0.27*0.48) # b = y + (0.74*q - 0.48*i) / (0.74*0.41 + 0.27*0.48) # g = y - (0.30*(r-y) + 0.11*(b-y)) / 0.59 r = y + 0.9468822170900693*i + 0.6235565819861433*q g = y - 0.27478764629897834*i - 0.6356910791873801*q b = y - 1.1085450346420322*i + 1.7090069284064666*q if r < 0.0: r = 0.0 if g < 0.0: g = 0.0 if b < 0.0: b = 0.0 if r > 1.0: r = 1.0 if g > 1.0: g = 1.0 if b > 1.0: b = 1.0 return (r, g, b) # HLS: Hue, Luminance, Saturation # H: position in the spectrum # L: color lightness # S: color saturation def rgb_to_hls(r, g, b): maxc = max(r, g, b) minc = min(r, g, b) sumc = (maxc+minc) rangec = (maxc-minc) l = sumc/2.0 if minc == maxc: return 0.0, l, 0.0 if l <= 0.5: s = rangec / sumc else: