RGB转24位色和24位色转RGB

对于常用的点云PCD文件，存储颜色信息通常由两种格式：

TYPE1：10727339
TYPE2：1.00512e-038

TYPE1

"""
36 46 58
"""

n = 2371130

def rgb_to_number(r,g,b):
	return （r*256+g)*256+b

def number_to_rgb(number: int):
    num = str(hex(number))
    r = int(num[2:4], 16)
    g = int(num[4:6], 16)
    b = int(num[6:8], 16)
    return [r, g, b]

print(number_to_rgb(n))

TYPE2

rgb = 1.00512e-038

i = struct.unpack('>l', rgb)[0]
# you can get back the float value by the inverse operations
pack = ctypes.c_uint32(i).value
r = (pack & 0x00FF0000) >> 16
g = (pack & 0x0000FF00) >> 8
b = (pack & 0x000000FF)