python-escpos/escpos/escpos.py

277 lines
8.4 KiB
Python

#!/usr/bin/python
'''
@author: Manuel F Martinez <manpaz@bashlinux.com>
@organization: Bashlinux
@copyright: Copyright (c) 2012 Bashlinux
@license: GPL
'''
import struct
import os
import time
import qrcode
import operator
from PIL import Image, ImageOps
from escpos.utils import *
from escpos.constants import *
from escpos.exceptions import *
class Escpos(object):
""" ESC/POS Printer object """
device = None
def _check_image_size(self, size):
""" Check and fix the size of the image to 32 bits """
if size % 32 == 0:
return (0, 0)
else:
image_border = 32 - (size % 32)
if (image_border % 2) == 0:
return (image_border // 2, image_border // 2)
else:
return (image_border // 2, image_border // 2 + 1)
def _print_image(self, imagedata, n_rows, col_bytes):
""" Print formatted image """
i = 0
cont = 0
buffer = ""
self._raw(S_RASTER_N)
buffer = struct.pack('<HH', col_bytes, n_rows)
self._raw(buffer)
self._raw(imagedata)
def fullimage(self, img, max_height=860, width=512, histeq=True, bandsize=255):
""" Resizes and prints an arbitrarily sized image """
if isinstance(img, Image.Image):
im = img.convert("RGB")
else:
im = Image.open(img).convert("RGB")
if histeq:
# Histogram equaliztion
h = im.histogram()
lut = []
for b in range(0, len(h), 256):
# step size
step = reduce(operator.add, h[b:b+256]) // 255
# create equalization lookup table
n = 0
for i in range(256):
lut.append(n // step)
n = n + h[i+b]
im = im.point(lut)
if width:
ratio = float(width) / im.size[0]
newheight = int(ratio * im.size[1])
# Resize the image
im = im.resize((width, newheight), Image.ANTIALIAS)
if max_height and im.size[1] > max_height:
im = im.crop((0, 0, im.size[0], max_height))
# Divide into bands
current = 0
while current < im.size[1]:
self.image(im.crop((0, current, width or im.size[0],
min(im.size[1], current + bandsize))))
current += bandsize
def image(self, im):
""" Parse image and prepare it to a printable format """
pixels = []
pix_line = ""
im_left = ""
im_right = ""
switch = 0
img_size = [ 0, 0 ]
if not isinstance(im, Image.Image):
im = Image.open(im)
im = im.convert("L")
im = ImageOps.invert(im)
im = im.convert("1")
if im.size[0] > 640:
print("WARNING: Image is wider than 640 and could be truncated at print time ")
if im.size[1] > 640:
raise ImageSizeError()
orig_width, height = im.size
width = ((orig_width + 31) // 32) * 32
new_image = Image.new("1", (width, height))
new_image.paste(im, (0, 0, orig_width, height))
the_bytes = new_image.tobytes()
self._print_image(the_bytes, n_rows=height, col_bytes=width//8)
def qr(self, text):
""" Print QR Code for the provided string """
qr_code = qrcode.QRCode(version=4, box_size=4, border=1, error_correction=qrcode.constants.ERROR_CORRECT_H)
qr_code.add_data(text)
qr_code.make(fit=True)
qr_img = qr_code.make_image()
# Convert the RGB image in printable image
im = qr_img._img.convert("1")
width = im.size[0]
height = im.size[1]
while width * 2 <= 640:
width *= 2
height *= 2
im = im.resize((width, height))
self.image(im)
self.text('\n')
def barcode(self, code, bc, height, width, pos, font):
""" Print Barcode """
# Align Bar Code()
self._raw(TXT_ALIGN_CT)
# Height
if 1 <= height <= 255:
self._raw(BARCODE_HEIGHT + chr(height))
else:
raise BarcodeSizeError("height = %s" % height)
# Width
if 2 <= width <= 6:
self._raw(BARCODE_WIDTH + chr(width))
else:
raise BarcodeSizeError("width = %s" % width)
# Font
if font.upper() == "B":
self._raw(BARCODE_FONT_B)
else: # DEFAULT FONT: A
self._raw(BARCODE_FONT_A)
# Position
if pos.upper() == "OFF":
self._raw(BARCODE_TXT_OFF)
elif pos.upper() == "BOTH":
self._raw(BARCODE_TXT_BTH)
elif pos.upper() == "ABOVE":
self._raw(BARCODE_TXT_ABV)
else: # DEFAULT POSITION: BELOW
self._raw(BARCODE_TXT_BLW)
# Type
if bc.upper() == "UPC-A":
self._raw(BARCODE_UPC_A)
elif bc.upper() == "UPC-E":
self._raw(BARCODE_UPC_E)
elif bc.upper() == "EAN13":
self._raw(BARCODE_EAN13)
elif bc.upper() == "EAN8":
self._raw(BARCODE_EAN8)
elif bc.upper() == "CODE39":
self._raw(BARCODE_CODE39)
elif bc.upper() == "ITF":
self._raw(BARCODE_ITF)
elif bc.upper() in ("NW7", "CODABAR"):
self._raw(BARCODE_NW7)
else:
raise BarcodeTypeError(bc)
# Print Code
if code:
self._raw(code)
else:
raise exception.BarcodeCodeError()
def text(self, txt):
""" Print alpha-numeric text """
if txt:
self._raw(txt.encode('cp936'))
else:
raise TextError()
def set(self, align='left', font='a', type='normal', width=1, height=1):
""" Set text properties """
# Width
if height != 2 and width != 2: # DEFAULT SIZE: NORMAL
self._raw(TXT_NORMAL)
if height == 2:
self._raw(TXT_2HEIGHT)
if width == 2:
self._raw(TXT_2WIDTH)
if height == 2 and width == 2:
self._raw(TXT_4SQUARE)
# Type
if type.upper() == "B":
self._raw(TXT_BOLD_ON)
self._raw(TXT_UNDERL_OFF)
elif type.upper() == "U":
self._raw(TXT_BOLD_OFF)
self._raw(TXT_UNDERL_ON)
elif type.upper() == "U2":
self._raw(TXT_BOLD_OFF)
self._raw(TXT_UNDERL2_ON)
self._raw(TXT_ITALIC_OFF)
elif type.upper() == "BU":
self._raw(TXT_BOLD_ON)
self._raw(TXT_UNDERL_ON)
elif type.upper() == "BU2":
self._raw(TXT_BOLD_ON)
self._raw(TXT_UNDERL2_ON)
elif type.upper == "NORMAL":
self._raw(TXT_BOLD_OFF)
self._raw(TXT_UNDERL_OFF)
# Font
if font.upper() == "B":
self._raw(TXT_FONT_B)
else: # DEFAULT FONT: A
self._raw(TXT_FONT_A)
# Align
if align.upper() == "CENTER":
self._raw(TXT_ALIGN_CT)
elif align.upper() == "RIGHT":
self._raw(TXT_ALIGN_RT)
elif align.upper() == "LEFT":
self._raw(TXT_ALIGN_LT)
def cut(self, mode=''):
""" Cut paper """
# Fix the size between last line and cut
# TODO: handle this with a line feed
self._raw("\n\n\n\n\n\n")
if mode.upper() == "PART":
self._raw(PAPER_PART_CUT)
else: # DEFAULT MODE: FULL CUT
self._raw(PAPER_FULL_CUT)
def cashdraw(self, pin):
""" Send pulse to kick the cash drawer """
if pin == 2:
self._raw(CD_KICK_2)
elif pin == 5:
self._raw(CD_KICK_5)
else:
raise CashDrawerError()
def hw(self, hw):
""" Hardware operations """
if hw.upper() == "INIT":
self._raw(HW_INIT)
elif hw.upper() == "SELECT":
self._raw(HW_SELECT)
elif hw.upper() == "RESET":
self._raw(HW_RESET)
else: # DEFAULT: DOES NOTHING
pass
def control(self, ctl):
""" Feed control sequences """
if ctl.upper() == "LF":
self._raw(CTL_LF)
elif ctl.upper() == "FF":
self._raw(CTL_FF)
elif ctl.upper() == "CR":
self._raw(CTL_CR)
elif ctl.upper() == "HT":
self._raw(CTL_HT)
elif ctl.upper() == "VT":
self._raw(CTL_VT)