class SegColorMap(object):
def __init__(self, alpha=0.8):
my_seg_map = np.array([
[0, 0, 0, 0],
[10, 170, 28, 0], # green
[232, 167, 4, 0], # orange
[43, 84, 206, 0], # blue
[230, 230, 0, 0], # yellow
[234., 9, 9, 0]
] # red
)
self.np_cmap = (my_seg_map - np.min(my_seg_map)) / (
np.max(my_seg_map) - np.min(my_seg_map))
self.np_cmap[..., -1] = alpha
# make sure the BACKGROUND class is completely transparant
self.np_cmap[0, -1] = 0
self.cmap = ListedColormap(self.np_cmap)
self.cmap._init()
self.cmap._lut[0, -1] = 0
self.cmap._lut[:, -1] = np.linspace(0, alpha, len(my_seg_map) + 3)
def convert_multi_labels(self, label_array):
if label_array.dtype != np.int:
label_array = label_array.astype(np.uint)
return self.np_cmap[label_array]
def _init(self):
# convert to lab
lab_colors = convert_rgb2lab(self.init_colors)
# initialize new list
colors = []
# iterate over stops
stops = self.get_stops()
for j in range(len(self.init_colors) - 1):
# interpolate between stops in lab
for i in np.linspace(stops[j], stops[j + 1], self.N / (len(stops) - 1)):
colors.append(lab_colors[j] * (1 - i) + i * lab_colors[j + 1])
# convert back to rgb
self.colors = convert_lab2rgb(colors)
# initialize a listed colormap
ListedColormap._init(self)
def joincmap(cmap1, cmap2, N=256):
"""
Join two colormaps and return one dynamic colormap.
"""
if isinstance(cmap1, str):
cmap1 = plt.get_cmap(cmap1)
if isinstance(cmap2, str):
cmap2 = plt.get_cmap(cmap2)
cmap = ListedColormap(
np.vstack((cmap1(np.linspace(0, 1,
N // 2)), cmap2(np.linspace(0, 1,
N // 2)))),
'->'.join((cmap1.name, cmap2.name)), N)
cmap._init()
cmap.values = np.linspace(-1, 1, N)
cmap.hinge = 0
return DynamicColormap(cmap)
