def getStartingColors(self, hueFilters=[], lightnessRange=[25,85],
onlyUseRGB=True):
"""Randomly select a starting color from a subset of CIE Lab space.
This function returns a set of highly preferable colors within a
subspace of the typical 8,325-color CIE Lab space that fall within the
range of any hue filters. Rather than the normal every-5 interval, the
subspace specifies an every-15 interval along L, a, and b axis starting
at the origin.
Args:
hueFilters (np.array): an n by 2 nd.array specifying lower and upper
hue filter bounds that fall within [0,360) degrees.
lightnessRange (list): a two-element list that sets the lightness
range for filtering for color space before sampling.
onlyUseRGB (bool): whether color space should be restricted to RGB.
Returns:
startingColors (np.array): an n x 3 array of n highly preferable CIE
Lab D65 starting colors.
"""
hueFilters = np.array(hueFilters)
lIntervals = CIE_LAB_STARTING_SUBSPACE_INTERVALS["L"]
aIntervals = CIE_LAB_STARTING_SUBSPACE_INTERVALS["a"]
bIntervals = CIE_LAB_STARTING_SUBSPACE_INTERVALS["b"]
isInterval = np.zeros((self.colorSpaces.shape[0], 3))
isInterval[:,0] = np.in1d(self.colorSpaces[:,0], lIntervals)
isInterval[:,1] = np.in1d(self.colorSpaces[:,1], aIntervals)
isInterval[:,2] = np.in1d(self.colorSpaces[:,2], bIntervals)
isIntervalMask = np.all(isInterval, axis=1)
startColors = self.colorSpaces[isIntervalMask]
isRGB = np.logical_and(startColors[:,[6,7,8]] >= 0, startColors[:,[6,7,8]] <= 255)
isRGB = np.all(isRGB, axis=1)
if lightnessRange[0] <= 10:
minLightness = 0
else:
minLightness = lightnessRange[0] + 0.01
if lightnessRange[1] <= 15:
maxLightness = 15
else:
maxLightness = lightnessRange[1]
inLightness = np.logical_not(np.logical_or(startColors[:,0] <
minLightness, startColors[:,0] > maxLightness))
startColors = startColors[np.logical_and(isRGB, inLightness)]
if hueFilters.size > 0:
hueFilters = convert.convertHueRanges(hueFilters)
okHue = [np.logical_and(startColors[:,3] >= low,
startColors[:,3] <= high) for low,high in hueFilters]
okHue = np.any(np.array(okHue), axis=0)
startColors = startColors[okHue]
# With the remaining subspace, enumerate all unique color pairs.
# For efficiency, unique pairs are calculated via one of the triangles
# of the cartesian product of all remaining colors.
labs = startColors[:,:3]
color_col_products = [cartesian((labs[:,i],labs[:,i]))
for i in xrange(labs.shape[1])]
productSize = (color_col_products[0].shape[0],2*len(color_col_products))
color_product = np.zeros(productSize)
for i, d in enumerate(color_col_products):
color_product[:,i] = d[:,0]
color_product[:,i+len(color_col_products)] = d[:,0]
idxs = np.transpose(np.array(np.triu_indices(len(labs),1)))
colorPairs = np.ascontiguousarray(labs[idxs,].reshape((-1, 6)))
colorPairPreferenceScores = npc.score(colorPairs)[:,2]
# Penalize preference scores for colors that are ``ugly''.
labs1 = np.ascontiguousarray(colorPairs[:,:3])
labs2 = np.ascontiguousarray(colorPairs[:,3:6])
penalties = np.minimum(npc.scorePenalty(labs1)[:,0],
npc.scorePenalty(labs2)[:,0])
colorPairPreferenceScores = colorPairPreferenceScores * penalties
maxPref = np.max(colorPairPreferenceScores)
stdPref = np.std(colorPairPreferenceScores)
prefThreshold = maxPref - 0.75*stdPref
colorPairs = colorPairs[colorPairPreferenceScores > prefThreshold,]
# Extract the unique colors from color combination list
# http://stackoverflow.com/questions/16970982
def getUnique(a):
a = colorPairs[:,:3]
b = np.ascontiguousarray(a).view(np.dtype((np.void, a.dtype.itemsize * a.shape[1])))
_, idx = np.unique(b, return_index=True)
return a[idx]
uniq1 = getUnique(colorPairs[:,:3])
uniq2 = getUnique(colorPairs[:,3:])
startingColors = getUnique( np.vstack(( uniq1, uniq2 )) )
return startingColors
def getStartingColors(self,
hueFilters=[],
lightnessRange=[25, 85],
onlyUseRGB=True):
"""Randomly select a starting color from a subset of CIE Lab space.
This function returns a set of highly preferable colors within a
subspace of the typical 8,325-color CIE Lab space that fall within the
range of any hue filters. Rather than the normal every-5 interval, the
subspace specifies an every-15 interval along L, a, and b axis starting
at the origin.
Args:
hueFilters (np.array): an n by 2 nd.array specifying lower and upper
hue filter bounds that fall within [0,360) degrees.
lightnessRange (list): a two-element list that sets the lightness
range for filtering for color space before sampling.
onlyUseRGB (bool): whether color space should be restricted to RGB.
Returns:
startingColors (np.array): an n x 3 array of n highly preferable CIE
Lab D65 starting colors.
"""
hueFilters = np.array(hueFilters)
lIntervals = CIE_LAB_STARTING_SUBSPACE_INTERVALS["L"]
aIntervals = CIE_LAB_STARTING_SUBSPACE_INTERVALS["a"]
bIntervals = CIE_LAB_STARTING_SUBSPACE_INTERVALS["b"]
isInterval = np.zeros((self.colorSpaces.shape[0], 3))
isInterval[:, 0] = np.in1d(self.colorSpaces[:, 0], lIntervals)
isInterval[:, 1] = np.in1d(self.colorSpaces[:, 1], aIntervals)
isInterval[:, 2] = np.in1d(self.colorSpaces[:, 2], bIntervals)
isIntervalMask = np.all(isInterval, axis=1)
startColors = self.colorSpaces[isIntervalMask]
isRGB = np.logical_and(startColors[:, [6, 7, 8]] >= 0,
startColors[:, [6, 7, 8]] <= 255)
isRGB = np.all(isRGB, axis=1)
if lightnessRange[0] <= 10:
minLightness = 0
else:
minLightness = lightnessRange[0] + 0.01
if lightnessRange[1] <= 15:
maxLightness = 15
else:
maxLightness = lightnessRange[1]
inLightness = np.logical_not(
np.logical_or(startColors[:, 0] < minLightness,
startColors[:, 0] > maxLightness))
startColors = startColors[np.logical_and(isRGB, inLightness)]
if hueFilters.size > 0:
hueFilters = convert.convertHueRanges(hueFilters)
okHue = [
np.logical_and(startColors[:, 3] >= low,
startColors[:, 3] <= high)
for low, high in hueFilters
]
okHue = np.any(np.array(okHue), axis=0)
startColors = startColors[okHue]
# With the remaining subspace, enumerate all unique color pairs.
# For efficiency, unique pairs are calculated via one of the triangles
# of the cartesian product of all remaining colors.
labs = startColors[:, :3]
color_col_products = [
cartesian((labs[:, i], labs[:, i])) for i in xrange(labs.shape[1])
]
productSize = (color_col_products[0].shape[0],
2 * len(color_col_products))
color_product = np.zeros(productSize)
for i, d in enumerate(color_col_products):
color_product[:, i] = d[:, 0]
color_product[:, i + len(color_col_products)] = d[:, 0]
idxs = np.transpose(np.array(np.triu_indices(len(labs), 1)))
colorPairs = np.ascontiguousarray(labs[idxs, ].reshape((-1, 6)))
colorPairPreferenceScores = npc.score(colorPairs)[:, 2]
# Penalize preference scores for colors that are ``ugly''.
labs1 = np.ascontiguousarray(colorPairs[:, :3])
labs2 = np.ascontiguousarray(colorPairs[:, 3:6])
penalties = np.minimum(
npc.scorePenalty(labs1)[:, 0],
npc.scorePenalty(labs2)[:, 0])
colorPairPreferenceScores = colorPairPreferenceScores * penalties
maxPref = np.max(colorPairPreferenceScores)
stdPref = np.std(colorPairPreferenceScores)
prefThreshold = maxPref - 0.75 * stdPref
colorPairs = colorPairs[colorPairPreferenceScores > prefThreshold, ]
# Extract the unique colors from color combination list
# http://stackoverflow.com/questions/16970982
def getUnique(a):
a = colorPairs[:, :3]
b = np.ascontiguousarray(a).view(
np.dtype((np.void, a.dtype.itemsize * a.shape[1])))
_, idx = np.unique(b, return_index=True)
return a[idx]
uniq1 = getUnique(colorPairs[:, :3])
uniq2 = getUnique(colorPairs[:, 3:])
startingColors = getUnique(np.vstack((uniq1, uniq2)))
return startingColors
def make(self, palSize, hueFilters=[], lightnessRange=[25,85],
onlyUseRGB=True, noticeableDifferenceAngle=1.0/3.0, startPalette=[],
weights={"ciede2000":1,"nameDifference":1,"nameUniqueness":0,
"pairPreference":1}):
"""Make a palette with palSize colors by sampling using weights.
Args:
palSize (int): the number of colors to sample for the palette.
hueFilters (list): a two-dimensional list, such that each element of
hue filters is a two-element list that contains the lower and
upper hue angle boundary for each hue angle region to include
when sampling colors.
lightnessRange (list): a two-element list that sets the lightness
range for filtering for color space before sampling.
onlyUseRGB (bool): whether color space should be restricted to RGB.
noticeableDifferenceAngle (float): the visual angle that should be
used when calculating CIE Lab noticeable difference intervals
using Stone, Szafir, and Setlur's engineering color difference
model http://www.danielleszafir.com/2014CIC_48_Stone_v3.pdf.
startPalette (list): a two-dimensional list, such that each element
of startPalette is a 3-element list that specifies a valid CIE
Lab D65 color. Any dimension that are not a multiple of 5 will
be rounded accordingly.
weights (dict): user-defined weights ([0,1]) for the four palette
scores such that the total weight always sums to 1. The weight
names are `ciede2000`, `nameDifference`, `nameUniqueness`, and
`pairPreference`.
Returns:
palette (np.ndarray): an array of CIE Lab D65 colors.
"""
assert isinstance(palSize, ( int, long )) and palSize > 0
assert "ciede2000" in weights and "nameDifference" in weights and\
"nameUniqueness" in weights and "pairPreference" in weights
assert np.sum([weights[w] >= 0.0 and weights[w] <= 1.0
for w in weights]) == 4
hueFilters = np.array(hueFilters)
hueFilters = convert.convertHueRanges(hueFilters)
startPalette = list(startPalette)
ndL, ndA, ndB = [d*3 for d in jnd.cieLabJND(noticeableDifferenceAngle)]
if len(startPalette) > 0:
palette = startPalette
else:
possibleStartColors = self.getStartingColors(hueFilters=hueFilters,
lightnessRange=lightnessRange, onlyUseRGB=onlyUseRGB)
startColorIdx = np.random.choice(possibleStartColors.shape[0])
palette = [possibleStartColors[startColorIdx]]
if len(palette) >= palSize:
return palette
colorSpaces = self.colorSpaces
nus = self.nameUniquenesses
if hueFilters.size > 0:
okHue = [np.logical_and(colorSpaces[:,3] >= low,
colorSpaces[:,3] <= high) for low,high in hueFilters]
okHue = np.any(np.array(okHue), axis=0)
colorSpaces = colorSpaces[okHue]
nus = nus[okHue]
isRGB = np.logical_and(colorSpaces[:,[6,7,8]] >= 0, colorSpaces[:,[6,7,8]] <= 255)
isRGB = np.all(isRGB, axis=1)
minLightness = lightnessRange[0] + 0.01
maxLightness = lightnessRange[1]
inLightness = np.logical_not(np.logical_or(colorSpaces[:,0] <
minLightness, colorSpaces[:,0] > maxLightness))
rgbAndLightnessMask = np.logical_and(isRGB, inLightness)
colorSpaces = colorSpaces[rgbAndLightnessMask]
nus = nus[rgbAndLightnessMask]
# filter ``ugly'' colors
# TODO push this to the scorePenalty C function as a 0 weighting
isUgly = np.zeros((colorSpaces.shape[0], 4))
isUgly[:,0] = colorSpaces[:,3] >= 85
isUgly[:,1] = colorSpaces[:,3] <= 114
isUgly[:,2] = colorSpaces[:,0] <= 75
isUgly[:,3] = colorSpaces[:,0] >= 35
isUglyMask = np.logical_not(np.all(isUgly, axis=1))
colorSpaces = colorSpaces[isUglyMask]
nus = nus[isUglyMask]
# remove any colors that aren't noticeably different from start palette
for color in palette:
diffs = np.absolute(colorSpaces[:,0:3] - color)
isND = np.logical_or(diffs[:,0] >= ndL,
np.logical_or(diffs[:,1] >= ndA, diffs[:,2] >= ndB))
colorSpaces = colorSpaces[isND]
nus = nus[isND]
if colorSpaces.shape[0] == 0:
print 'Ran out of candidates.'
return np.array(palette)
lab = colorSpaces[:,0:3]
lch = colorSpaces[:,[0,4,3]]
rgb = colorSpaces[:,6:]
candidates = lab
scorePenalty = npc.scorePenalty(np.ascontiguousarray(candidates))[:,0]
# apply the name uniqueness weight to all NU values
nus *= weights["nameUniqueness"]
nus = nus.reshape( (nus.shape[0], 1) ) # reshape for join
startPalSize = len(palette)
# TODO memoize loop s.t. previous results don't need to be recomputed
for pi in xrange(palSize - startPalSize):
# create combinations of candidates + palette colors
# Each tile stores a candidate color paired with a palette color
tiled = np.tile(candidates, (pi+startPalSize, 1))
tiled = np.hstack(( tiled,
np.zeros(tiled.shape[0]*3).reshape(tiled.shape[0], 3) ))
for i, p in enumerate(palette):
tiled[:,3:] = p
# stack the tiles to into the score ufunc format (2 Lab colors/row)
scores = npc.score( np.ascontiguousarray(tiled) )[:,0:3]
# reshape the 2 Lab colors/row so that each row is instead a
# potential candidate and the columns are its scores to all of the
# already-picked palette colors
scores = np.hstack(np.split(scores,pi+startPalSize))
# Take the minimum value for each candidate score
des = scores[:,0::3].min(axis=1)
nds = scores[:,1::3].min(axis=1)
pps = scores[:,2::3].min(axis=1)
# Normalize CIEDE2000 and Pair Preference to [0,1] to match the Name
# Difference and Name Uniqueness scores
# The following distance bounds are precomputed from the 8325 colors in the dataset
maxDistance = 122.48163103
minDistance = 1.02043527056
des = (des - minDistance) / (maxDistance - minDistance)
maxPreference = 107.909
minPreference = -101.423
pps = (pps - minPreference) / (maxPreference - minPreference)
# apply weights to the palette scores
des *= weights["ciede2000"]
nds *= weights["nameDifference"]
pps *= weights["pairPreference"]
# reshape scores for stacking
des = des.reshape( (des.shape[0], 1) )
nds = nds.reshape( (nds.shape[0], 1) )
pps = pps.reshape( (pps.shape[0], 1) )
scores = np.hstack( (des, nds, pps, nus) )
scores = np.sum(scores, axis=1)
# apply the ugly-color penalty function
scores *= scorePenalty
# sample a color above the score threshold limit
threshold = np.max(scores) - 0.75*np.std(scores)
choices = candidates[ scores > threshold, :]
# If the thresholding yielded no candidates, don't perform it
# This typically happens with low (i.e., 1) color candidate sets
if choices.shape[0] == 0:
choices = candidates
choice = choices[np.random.choice(choices.shape[0])]
palette = palette + [choice]
# Prune choice and not noticeably different colors from sample space
diffs = np.absolute(candidates-choice)
isND = np.logical_or(diffs[:,0] >= ndL, np.logical_or(diffs[:,1] >=
ndA, diffs[:,2] >= ndB))
candidates = candidates[isND]
nus = nus[isND]
scorePenalty = scorePenalty[isND]
if candidates.shape[0] == 0:
print 'Ran out when picking color #'+str(pi)
break
return np.array(palette)
def make(
self,
palSize,
hueFilters=[],
lightnessRange=[25, 85],
onlyUseRGB=True,
noticeableDifferenceAngle=1.0 / 3.0,
startPalette=[],
weights={
"ciede2000": 1,
"nameDifference": 1,
"nameUniqueness": 0,
"pairPreference": 1
}):
"""Make a palette with palSize colors by sampling using weights.
Args:
palSize (int): the number of colors to sample for the palette.
hueFilters (list): a two-dimensional list, such that each element of
hue filters is a two-element list that contains the lower and
upper hue angle boundary for each hue angle region to include
when sampling colors.
lightnessRange (list): a two-element list that sets the lightness
range for filtering for color space before sampling.
onlyUseRGB (bool): whether color space should be restricted to RGB.
noticeableDifferenceAngle (float): the visual angle that should be
used when calculating CIE Lab noticeable difference intervals
using Stone, Szafir, and Setlur's engineering color difference
model http://www.danielleszafir.com/2014CIC_48_Stone_v3.pdf.
startPalette (list): a two-dimensional list, such that each element
of startPalette is a 3-element list that specifies a valid CIE
Lab D65 color. Any dimension that are not a multiple of 5 will
be rounded accordingly.
weights (dict): user-defined weights ([0,1]) for the four palette
scores such that the total weight always sums to 1. The weight
names are `ciede2000`, `nameDifference`, `nameUniqueness`, and
`pairPreference`.
Returns:
palette (np.ndarray): an array of CIE Lab D65 colors.
"""
assert isinstance(palSize, (int, long)) and palSize > 0
assert "ciede2000" in weights and "nameDifference" in weights and\
"nameUniqueness" in weights and "pairPreference" in weights
assert np.sum(
[weights[w] >= 0.0 and weights[w] <= 1.0 for w in weights]) == 4
hueFilters = np.array(hueFilters)
hueFilters = convert.convertHueRanges(hueFilters)
startPalette = list(startPalette)
ndL, ndA, ndB = [
d * 3 for d in jnd.cieLabJND(noticeableDifferenceAngle)
]
if len(startPalette) > 0:
palette = startPalette
else:
possibleStartColors = self.getStartingColors(
hueFilters=hueFilters,
lightnessRange=lightnessRange,
onlyUseRGB=onlyUseRGB)
startColorIdx = np.random.choice(possibleStartColors.shape[0])
palette = [possibleStartColors[startColorIdx]]
if len(palette) >= palSize:
return palette
colorSpaces = self.colorSpaces
nus = self.nameUniquenesses
if hueFilters.size > 0:
okHue = [
np.logical_and(colorSpaces[:, 3] >= low,
colorSpaces[:, 3] <= high)
for low, high in hueFilters
]
okHue = np.any(np.array(okHue), axis=0)
colorSpaces = colorSpaces[okHue]
nus = nus[okHue]
isRGB = np.logical_and(colorSpaces[:, [6, 7, 8]] >= 0,
colorSpaces[:, [6, 7, 8]] <= 255)
isRGB = np.all(isRGB, axis=1)
minLightness = lightnessRange[0] + 0.01
maxLightness = lightnessRange[1]
inLightness = np.logical_not(
np.logical_or(colorSpaces[:, 0] < minLightness,
colorSpaces[:, 0] > maxLightness))
rgbAndLightnessMask = np.logical_and(isRGB, inLightness)
colorSpaces = colorSpaces[rgbAndLightnessMask]
nus = nus[rgbAndLightnessMask]
# filter ``ugly'' colors
# TODO push this to the scorePenalty C function as a 0 weighting
isUgly = np.zeros((colorSpaces.shape[0], 4))
isUgly[:, 0] = colorSpaces[:, 3] >= 85
isUgly[:, 1] = colorSpaces[:, 3] <= 114
isUgly[:, 2] = colorSpaces[:, 0] <= 75
isUgly[:, 3] = colorSpaces[:, 0] >= 35
isUglyMask = np.logical_not(np.all(isUgly, axis=1))
colorSpaces = colorSpaces[isUglyMask]
nus = nus[isUglyMask]
# remove any colors that aren't noticeably different from start palette
for color in palette:
diffs = np.absolute(colorSpaces[:, 0:3] - color)
isND = np.logical_or(
diffs[:, 0] >= ndL,
np.logical_or(diffs[:, 1] >= ndA, diffs[:, 2] >= ndB))
colorSpaces = colorSpaces[isND]
nus = nus[isND]
if colorSpaces.shape[0] == 0:
print 'Ran out of candidates.'
return np.array(palette)
lab = colorSpaces[:, 0:3]
lch = colorSpaces[:, [0, 4, 3]]
rgb = colorSpaces[:, 6:]
candidates = lab
scorePenalty = npc.scorePenalty(np.ascontiguousarray(candidates))[:, 0]
# apply the name uniqueness weight to all NU values
nus *= weights["nameUniqueness"]
nus = nus.reshape((nus.shape[0], 1)) # reshape for join
startPalSize = len(palette)
# TODO memoize loop s.t. previous results don't need to be recomputed
for pi in xrange(palSize - startPalSize):
# create combinations of candidates + palette colors
# Each tile stores a candidate color paired with a palette color
tiled = np.tile(candidates, (pi + startPalSize, 1))
tiled = np.hstack(
(tiled,
np.zeros(tiled.shape[0] * 3).reshape(tiled.shape[0], 3)))
for i, p in enumerate(palette):
tiled[:, 3:] = p
# stack the tiles to into the score ufunc format (2 Lab colors/row)
scores = npc.score(np.ascontiguousarray(tiled))[:, 0:3]
# reshape the 2 Lab colors/row so that each row is instead a
# potential candidate and the columns are its scores to all of the
# already-picked palette colors
scores = np.hstack(np.split(scores, pi + startPalSize))
# Take the minimum value for each candidate score
des = scores[:, 0::3].min(axis=1)
nds = scores[:, 1::3].min(axis=1)
pps = scores[:, 2::3].min(axis=1)
# Normalize CIEDE2000 and Pair Preference to [0,1] to match the Name
# Difference and Name Uniqueness scores
# The following distance bounds are precomputed from the 8325 colors in the dataset
maxDistance = 122.48163103
minDistance = 1.02043527056
des = (des - minDistance) / (maxDistance - minDistance)
maxPreference = 107.909
minPreference = -101.423
pps = (pps - minPreference) / (maxPreference - minPreference)
# apply weights to the palette scores
des *= weights["ciede2000"]
nds *= weights["nameDifference"]
pps *= weights["pairPreference"]
# reshape scores for stacking
des = des.reshape((des.shape[0], 1))
nds = nds.reshape((nds.shape[0], 1))
pps = pps.reshape((pps.shape[0], 1))
scores = np.hstack((des, nds, pps, nus))
scores = np.sum(scores, axis=1)
# apply the ugly-color penalty function
scores *= scorePenalty
# sample a color above the score threshold limit
threshold = np.max(scores) - 0.75 * np.std(scores)
choices = candidates[scores > threshold, :]
# If the thresholding yielded no candidates, don't perform it
# This typically happens with low (i.e., 1) color candidate sets
if choices.shape[0] == 0:
choices = candidates
choice = choices[np.random.choice(choices.shape[0])]
palette = palette + [choice]
# Prune choice and not noticeably different colors from sample space
diffs = np.absolute(candidates - choice)
isND = np.logical_or(
diffs[:, 0] >= ndL,
np.logical_or(diffs[:, 1] >= ndA, diffs[:, 2] >= ndB))
candidates = candidates[isND]
nus = nus[isND]
scorePenalty = scorePenalty[isND]
if candidates.shape[0] == 0:
print 'Ran out when picking color #' + str(pi)
break
return np.array(palette)