#
# 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA.
#
"""
Python barcode renderer for Code39 barcodes. Designed for use with Inkscape.
"""
from Base import Barcode
ENCODE = {
'0': '000110100',
'1': '100100001',
'2': '001100001',
'3': '101100000',
'4': '000110001',
'5': '100110000',
'6': '001110000',
'7': '000100101',
'8': '100100100',
'9': '001100100',
'A': '100001001',
'B': '001001001',
'C': '101001000',
'D': '000011001',
'E': '100011000',
'F': '001011000',
'G': '000001101',
'H': '100001100',
'I': '001001100',
'J': '000011100',
'K': '100000011',
'L': '001000011',
'M': '101000010',
'N': '000010011',
'O': '100010010',
'P': '001010010',
'Q': '000000111',
'R': '100000110',
'S': '001000110',
'T': '000010110',
'U': '110000001',
'V': '011000001',
'W': '111000000',
'X': '010010001',
'Y': '110010000',
'Z': '011010000',
'-': '010000101',
'*': '010010100',
'+': '010001010',
'$': '010101000',
'%': '000101010',
'/': '010100010',
'.': '110000100',
' ': '011000100',
}
class Code39(Barcode):
"""Convert a text into string binary of black and white markers"""
def encode(self, text):
self.text = text.upper()
result = ''
# It isposible for us to encode code39
# into full ascii, but this feature is
# not enabled here
for char in '*' + self.text + '*':
if not ENCODE.has_key(char):
char = '-'
result = result + ENCODE[char] + '0'
# Now we need to encode the code39, best read
# the code to understand what it's up to:
encoded = ''
colour = '1' # 1 = Black, 0 = White
for data in result:
if data == '1':
encoded = encoded + colour + colour
else:
encoded = encoded + colour
colour = colour == '1' and '0' or '1'
return encoded