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diff --git a/share/extensions/barcode/BaseEan.py b/share/extensions/barcode/BaseEan.py
new file mode 100644
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+++ b/share/extensions/barcode/BaseEan.py
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+# coding=utf-8
+#
+# Copyright (C) 2010 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.
+#
+"""
+Some basic common code shared between EAN and UCP generators.
+"""
+
+from .Base import Barcode, TEXT_POS_TOP
+
+try:
+    from typing import Optional, List, Dict
+except ImportError:
+    pass
+
+MAPPING = [
+    # Left side of barcode Family '0'
+    ["0001101", "0011001", "0010011", "0111101", "0100011",
+     "0110001", "0101111", "0111011", "0110111", "0001011"],
+    # Left side of barcode Family '1' and flipped to right side.
+    ["0100111", "0110011", "0011011", "0100001", "0011101",
+     "0111001", "0000101", "0010001", "0001001", "0010111"],
+]
+# This chooses which of the two encodings above to use.
+FAMILIES = ('000000', '001011', '001101', '001110', '010011',
+            '011001', '011100', '010101', '010110', '011010')
+
+
+class EanBarcode(Barcode):
+    """Simple base class for all EAN type barcodes"""
+    lengths = None # type: Optional[List[int]]
+    length = None # type: Optional[int]
+    checks = [] # type: List[int]
+    extras = {} # type: Dict[int, str] 
+    magic = 10
+    guard_bar = '202'
+    center_bar = '02020'
+
+    def intarray(self, number):
+        """Convert a string of digits into an array of ints"""
+        return [int(i) for i in number]
+
+    def encode_interleaved(self, family, number, fams=FAMILIES):
+        """Encode any side of the barcode, interleaved"""
+        result = []
+        encset = self.intarray(fams[family])
+        for i in range(len(number)):
+            thismap = MAPPING[encset[i]]
+            result.append(thismap[number[i]])
+        return result
+
+    def encode_right(self, number):
+        """Encode the right side of the barcode, non-interleaved"""
+        result = []
+        for num in number:
+            # The right side is always the reverse of the left's family '1'
+            result.append(MAPPING[1][num][::-1])
+        return result
+
+    def encode_left(self, number):
+        """Encode the left side of the barcode, non-interleaved"""
+        result = []
+        for num in number:
+            result.append(MAPPING[0][num])
+        return result
+
+    def space(self, *spacing):
+        """Space out an array of numbers"""
+        result = ''
+        for space in spacing:
+            if isinstance(space, list):
+                for i in space:
+                    result += str(i)
+            elif isinstance(space, int):
+                result += ' ' * space
+        return result
+
+    def get_lengths(self):
+        """Return a list of acceptable lengths"""
+        if self.length:
+            return [self.length]
+        return self.lengths[:]
+
+    def encode(self, code):
+        """Encode any EAN barcode"""
+        code = code.replace(' ', '').strip()
+        guide = code.endswith('>')
+        code = code.strip('>')
+
+        if not code.isdigit():
+            return self.error(code, 'Not a Number, must be digits 0-9 only')
+        lengths = self.get_lengths() + self.checks
+
+        # Allow extra barcodes after the first one
+        if len(code) not in lengths:
+            for extra in self.extras:
+                sep = len(code) - extra
+                if sep in lengths:
+                    # Generate a barcode along side this one.
+                    self.add_extra_barcode(self.extras[extra], text=code[sep:],
+                                           x=self.pos_x + 400 * self.scale, text_pos=TEXT_POS_TOP)
+                    code = code[:sep]
+
+        if len(code) not in lengths:
+            return self.error(code, 'Wrong size {:d}, must be {} digits'.format(len(code), ', '.join([str(length) for length in lengths])))
+
+        if self.checks:
+            if len(code) not in self.checks:
+                code = self.append_checksum(code)
+            elif not self.verify_checksum(code):
+                return self.error(code, 'Checksum failed, omit for new sum')
+        return self._encode(self.intarray(code), guide=guide)
+
+    def _encode(self, num, guide=False):
+        """
+        Write your EAN encoding function, it's passed in an array of int and
+        it should return a string on 1 and 0 for black and white parts
+        """
+        raise NotImplementedError("_encode should be provided by parent EAN")
+
+    def enclose(self, left, right=()):
+        """Standard Enclosure"""
+        parts = [self.guard_bar] + left
+        parts.append(self.center_bar)
+        parts += list(right) + [self.guard_bar]
+        return ''.join(parts)
+
+    def get_checksum(self, num):
+        """Generate a UPCA/EAN13/EAN8 Checksum"""
+        # Left to right,checksum based on first digits.
+        total = sum([int(n) * (3, 1)[x % 2] for x, n in enumerate(num[::-1])])
+        # Modulous result to a single digit checksum
+        checksum = self.magic - (total % self.magic)
+        if checksum < 0 or checksum >= self.magic:
+            return '0'
+        return str(checksum)
+
+    def append_checksum(self, number):
+        """Apply the checksum to a short number"""
+        return number + self.get_checksum(number)
+
+    def verify_checksum(self, number):
+        """Verify any checksum"""
+        return self.get_checksum(number[:-1]) == number[-1]