EAN8.py revision 040e298be5b23e77e33309d65449072183c82d5c
'''
Copyright (C) 2007 Martin Owens
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
'''
from Base import Barcode
import sys
leftMap = [ '0001101', '0011001', '0010011', '0111101', '0100011', '0110001', '0101111', '0111011', '0110111', '0001011' ]
rightMap = [ '1110010', '1100110', '1101100', '1000010', '1011100', '1001110', '1010000', '1000100', '1001000', '1110100' ]
weightMap = [ 3, 1, 3, 1, 3, 1, 3 ]
guardBar = '202';
centerBar = '02020';
class Object(Barcode):
def encode(self, number):
result = ''
# Rejig the label for use
self.label = number[:4] + ' ' + number[4:]
if len(number) < 7 or len(number) > 8 or not number.isdigit():
sys.stderr.write("Can not encode '" + number + "' into EAN8 Barcode, Size must be 7 or 8 Numbers only\n")
if len(number) == 7:
number = number + self.calculateChecksum(number)
result = result + guardBar
i = 0
for num in number:
if i >= 4:
result = result + rightMap[int(num)]
else:
result = result + leftMap[int(num)]
i = i + 1
if i == 4:
result = result + centerBar;
result = result + guardBar;
self.inclabel = ' ' + number[:4] + ' ' + number[4:]
return result;
def calculateChecksum(self, number):
weight = 0;
i = 0;
for num in number:
weight = weight + (int(num) * weightMap[i])
i = i + 1
weight = 10 - (weight % 10)
if weight == 10:
weight = 0
return str(weight);
def getStyle(self, index):
result = { 'width' : '1', 'top' : int(self.y), 'write' : True }
if index==0: # White Space
result['write'] = False
elif index==1: # Black Bar
result['height'] = int(self.height)
elif index==2: # Guide Bar
result['height'] = int(self.height) + 8
return result