mqtt-to-flipdot/FlipdotSender.py

from PIL import Image, ImageDraw, ImageFont
import socket
import binascii
import io
import time
import re

class FlipdotSender(object):
    '''
    classdocs
    '''
    
    C_BLACK = 0
    C_WHITE = 255

    def __init__(self, udphost, udpport, img_size=(80,16), font_size=8, font_size_scroll=12, 
                 font_offset1=(0,-1), font_offset2=(0,7), 
                 #font_family='/usr/share/fonts/gnu-free/FreeMono.ttf',
                 font_family='/usr/share/fonts/truetype/ttf-dejavu/DejaVuSansMono.ttf',
                 #font_family='/usr/share/fonts/truetype/freefont/FreeMono.ttf', 
                 
                 chars_per_line=11):
        '''
        Constructor
        '''
        
        self._udphost = udphost
        if not type(udpport) is int or udpport > 65536:
            raise TypeError('port has to be int and > 65536 !!')
        self._udpport = udpport
        self._img_size = img_size
        self._font_size = font_size
        self._font_size_scroll = font_size_scroll
        self._font_offset1 = font_offset1
        self._font_offset2 = font_offset2
        self._font_family = font_family
        self._chars_per_line = chars_per_line
        
        self._sock = socket.socket(socket.AF_INET6, socket.SOCK_DGRAM)
        
    
    def _list2byte(self, l):
        byte = 0
        i = 0
        for i in range(8):
            byte += 2**(7-i) if l[i] else 0
        return byte
    
    def _array2packet(self, a):        
        return [self._list2byte(a[i*8:i*8+8]) for i in range(int(len(a)/8))]
        
   
    def _send(self, image):
        imgmap = []
        for pixel in image.getdata():
            r, g, b, a = pixel
            if r == FlipdotSender.C_WHITE:
                imgmap.append(1)
            else:
                imgmap.append(0)
        
        packet = self._array2packet(imgmap)
        
        self._sock.sendto(bytes(packet), (self._udphost, self._udpport))
        
    def send_text(self, text):
        image = Image.new("RGBA", self._img_size, FlipdotSender.C_BLACK)
        draw = ImageDraw.Draw(image)
        draw.fontmode = "1"         # No AA
        
        font = ImageFont.truetype(self._font_family, self._font_size)
        
        cut = self._chars_per_line
            
        splitted_text = text.split("|")
        
        draw.text(self._font_offset1, splitted_text[0], font=font, fill=FlipdotSender.C_WHITE)
        if len(splitted_text)>1:
                draw.text(self._font_offset2, splitted_text[1], font=font, fill=FlipdotSender.C_WHITE)
        
        self._send(image)       
   
    def send_marquee(self, str, speed=3):
        offset = self._img_size[0]
        font = ImageFont.truetype(self._font_family, self._font_size_scroll)
        
        while offset >= -font.getsize(str)[0]-speed:
            image = Image.new("RGBA", self._img_size, FlipdotSender.C_BLACK)
            draw = ImageDraw.Draw(image)
            draw.fontmode = "1"         # No AA
        
            draw.text((offset,0), str, font=font, fill=FlipdotSender.C_WHITE)
            self._send(image)
            offset -= speed
            time.sleep(0.15)
        
    def send_img(self, img):
        background = Image.new("RGBA", self._img_size, FlipdotSender.C_BLACK)
        stream = io.BytesIO(img)
        image = Image.open(stream)
        image = image.convert(mode='RGBA')
        image = image.resize(self._img_size)
        image.save('/tmp/send2.jpeg', 'JPEG')
        background.paste(image, box=(0,0), mask=None)
        background.save('/tmp/send.jpeg', 'JPEG')
        
        self._send(background)