RGB888转换为RGB565原理及工具

1.原理
首先RGB的范围是0-255，包括RGB三个值。

第一步将R,G,B三个值分别转化为八位二进制数，这里以GREEN为例子。
GREEN R:0 G:255 B:0
二进制：R00000000 11111111 00000000

565的意思就是RGB的位数，R取5位，G取六位，B取5位。其中要求取高位，舍低位。

00000 000 11111111 00000 00

其中非粗体的 0和1 舍去

得到0000011111100000
再转化为十六进制数0x7e0

2.工具

#!/usr/bin/env python
# -*- coding: UTF-8 -*-from tkinter import *
import rewindow = Tk()
window.title("RGB888 转换 RGB565")
window.geometry('450x300+300+250')def scalecommand(color):#print(s1.get(),s2.get(),s3.get())b=s3.get()g=s2.get()r=s1.get()R = r & 0xF8G = g & 0xFcB = b & 0xF8rgb565 = (R << 8) | (G << 3) | (B >> 3)rgb888 = (r << 16) | (g << 8) | bR = R >> 3G = G >> 2B = B >> 3rgb888_text = 'RGB888: '+ "#%06x"%rgb888rgb888_Label.configure(text=rgb888_text)rgb565_text = '565: '+ "%d " %R + "%d " %G + "%d" %Brgb565_Label.configure(text=rgb565_text)#print("%#08X"%rgb)info_Label.configure(bg="#%06x" %rgb888)def HexToDec(value):try:return int(value, 16)except ValueError:return "Invalid Hexadecimal Value"def buttonClick1():# RGB888 转 RGB565try:c888 = int(rgb1_Entry.get(),16)         #字符转16进制整数except ValueError:print( "Invalid Hexadecimal Value")returnrgb2_Entry.delete(0,END)if c888 == None :returnelse:b = (c888 & 0xFF)                 #转换RB 取得rgb颜色Bg = int((c888 & 0xFF00) >> 8)         #转换G 取得rgb颜色Gr = int((c888 & 0xFF0000) >>16)     #转换R 取得rgb颜色RR = r & 0xF8                        #取得RGB565的5位RG = g & 0xFc                        #取得RGB565的6位GB = b & 0xF8                        #取得RGB565的5位Brgb565 = (R << 8) | (G << 3) | (B >> 3)                               #print("%#06x" %rgb565)               #设置滑块位置s1.set(r)               s2.set(g)s3.set(b)#显示RGB888和RGB565颜色码info_Label.configure(bg="#%06x" %c888)      rgb888_text = 'RGB888: '+ "#%06x"%c888rgb888_Label.configure(text=rgb888_text)rgb565_text = 'RGB565: '+ "%#06x" %rgb565rgb565_Label.configure(text=rgb565_text)def buttonClick2():# RGB565 转 RGB888rgb1_Entry.delete(0,END)try:c565 = int(rgb2_Entry.get(),16)except ValueError:print( "Invalid Hexadecimal Value")returnif c565 == None :returnelse:b = (c565 & 0x001F)                 #转换R g = int((c565 & 0x07E0))           #转换G r = int((c565 & 0xF800))          #转换BR = r >> 8G = g >> 3B = b << 3rgb888 = (R << 16) | (G << 8) | B        #print("%#06x" %rgb888)s1.set(R)s2.set(G)s3.set(B)info_Label.configure(bg="#%06x" %rgb888)rgb888_text = 'RGB888: '+ "#%06x"%rgb888rgb888_Label.configure(text=rgb888_text)rgb565_text = 'RGB565: '+ "%#06x" %c565rgb565_Label.configure(text=rgb565_text)Rgb1_Label = Label(window, text="RGB888 代码：",height = 2,fg='#191970')
Rgb1_Label.place( x =20, y = 25 , anchor=NW)R1_Label = Label(window, text="#",height = 2,fg='#191970')
R1_Label.place( x =20, y = 50 , anchor=NW)
rgb1_Entry = Entry(window,width=10)
rgb1_Entry.place( x =40, y = 60 , anchor=NW)Rgb2_Label = Label(window, text="RGB565 代码：",height = 2,fg='#191970')
Rgb2_Label.place( x =20, y = 85 , anchor=NW)R2_Label = Label(window, text="0x",height = 2,fg='#191970')
R2_Label.place( x =20, y = 110 , anchor=NW)
rgb2_Entry = Entry(window,width=10)
rgb2_Entry.place( x =40, y = 120 , anchor=NW)button1 = Button(window,text="转换", bg='#8FBC8F',command=buttonClick1)    #转换按键
button1.place( x =160, y = 40 , anchor=NW)button2 = Button(window,text="转换", bg='#8FBC8F',command=buttonClick2)    #转换按键
button2.place( x =160, y = 110 , anchor=NW)info_Label = Label(window, text="",height = 10,width=20)        #色块
info_Label.configure(bg='#FFFFFF')
info_Label.place( x =280, y = 20 , anchor=NW)R_Label = Label(window, text="R",height = 1,width=1)       
R_Label.place( x =20, y = 170 , anchor=NW)
s1 = Scale(window,  from_=0, to=255, orient=HORIZONTAL,length=200, showvalue=1, tickinterval=0, resolution=1, command=scalecommand)     #滑块R
s1.place( x =40, y = 150 , anchor=NW)G_Label = Label(window, text="G",height = 1,width=1)       
G_Label.place( x =20, y = 210 , anchor=NW)
s2 = Scale(window,  from_=0, to=255, orient=HORIZONTAL,length=200, showvalue=1, tickinterval=0, resolution=1, command=scalecommand)   #滑块G
s2.place( x =40, y = 190 , anchor=NW)B_Label = Label(window, text="B",height = 1,width=1)        
B_Label.place( x =20, y = 250 , anchor=NW)
s3 =  Scale(window, from_=0, to=255, orient=HORIZONTAL,length=200, showvalue=1, tickinterval=0, resolution=1, command=scalecommand)   #滑块B
s3.place( x =40, y = 230 , anchor=NW)rgb888_Label = Label(window, text="RGB888:",height = 1,width=18 , fg = 'blue',anchor="w")
rgb888_Label.place( x =280, y = 210 )rgb565_Label = Label(window, text="565:",height = 1,width=18 , fg = 'blue',anchor="w")  
rgb565_Label.place( x =280, y = 250 ) window.mainloop()