HDBn Decoder + test program

hdbn.py

#!/usr/bin/env python2.7
#-*- coding: utf8 -*-

from __future__ import print_function

class HDBn:
    """

    Classe d'implémentation d'HDBn

    param constr. :
        n -> nombre de bits avant un viol

    """

    def __init__(self, n=3):
        """ Constructeur """
        # nb bit avant viol
        self.n = n
        # init vals
        self.prev = -1
        self.viol = -1
        self.P = []
        self.N = []

    def out(self, b):
        """ Affichage """
        if b == -1:
            P.append(0)
            N.append(1)
        elif b == +1:
            P.append(1)
            N.append(0)
        elif b == 0:
            P.append(0)
            N.append(0)

    def whoami(self):
        """ Who Am I ? """
        print("i'm HDB{} decoder \\o/".format(self.n))


    def encode(self, data=[]):
        """ Decoder """

        print("D   P N")

        i = 0

        while i<len(data):
            if data[i] == 1:
                # envoi en inversant la polarité
                self.out(-self.prev)
                self.prev = -self.prev
                i += 1

            else: # on a donc un 0
                # si il ne reste pas assez de bit pour qu'un viol arrive, on envoie direct
                if i >= len(data)-(self.n+1):
                    self.out(data[i])
                    i += 1
                    continue

                if data[i+1]: # si ce n'est pas un zéro ensuite on envoie
                    self.out(0)
                    i += 1

                else:
                    # sinon : on enregistre la séquence de 0 et on envoie en conséquence
                    seq = []
                    for j in range(self.n+1):
                        if data[i+j] == 0:
                            seq.append(data[i+j])
                        else: break

                    if len(seq) >= self.n+1: # on a assez de 0
                        # on traite le viol
                        if self.viol == -1 and self.prev == -1:
                            seq[0] = +1
                            seq[-1] = +1
                        elif self.viol == -1 and self.prev == 1:
                            seq[-1] = +1
                        elif self.viol == 1 and self.prev == -1:
                            seq[-1] = -1
                        elif self.viol == 1 and self.prev == 1:
                            seq[0] = -1
                            seq[-1] = -1

                        self.prev = seq[-1]
                        self.viol = seq[-1]

                    for j in seq: self.out(j)
                    i += len(seq)

        return (P,N)

    def self.decode(P,N):
        """ Decoder """

        # re init
        self.viol = -1
        self.prev = -1

       pass 

main.py

#!/usr/bin/env python
#-*- coding: utf8 -*-

from hdbn import HDBn

def main():
    data = "10010100000011000011100"
    data = [int(_) for _ in data]

    coder = HDBn(2)

    coder.whoami()

    coder.encode(data)

if __name__=='__main__':
    main()