import math def bitsForInt(i): return math.ceil(math.log2(i)) # Utility classes class BitsPacker: def __init__(self): self.data= '' self.rem_bits=8 self.tmp_byte= 0 def packString(self, s): for c in s: self.pack(ord(c), 8) def pack(self, i, bits_count): ubits = bits_count - self.rem_bits if ubits>0: ti= i>>ubits self.tmp_byte |= ti self.data+= chr(self.tmp_byte) self.tmp_byte= 0 self.rem_bits= 8 self.pack(i&((1<= self.max_i: raise Exception('Out of range') ubits= bits_count - self.rem_bits curr= ord(self.data[self.curr_i]) if ubits > 0: r= curr&((1<>= (-ubits) self.rem_bits -= bits_count return curr & ((1 << bits_count) - 1) def eop(self): return self.curr_i>=self.max_i def encoder(data): symbs= {} last= None count= 0 series= [] # calculate series and symbols info for b in data: if b not in symbs: symbs[b]= {'count':0, 'max':0} symbs[b]['count']+=1 if last == None or b==last: count+=1 last= b else: series.append((last, count)) if count > symbs[last]['max']: symbs[last]['max']= count last= b count= 1 series.append((last, count)) if count > symbs[last]['max']: symbs[last]['max'] = count # max_bits_series= 0 symbs_str= '' for s in symbs: curr= symbs[s] curr['rep_bits']= bitsForInt(curr['max']) symbs_str+= s if curr['rep_bits'] > max_bits_series: max_bits_series= curr['rep_bits'] # calculate the repetition block (like int) bits_for_max_bits = bitsForInt(max_bits_series) symbs_count = len(symbs) symb_bits = bitsForInt(len(symbs)) bp = BitsPacker() # pack symbols count bp.pack(symbs_count, 8) # pack symbols bp.packString(symbs_str) # calculate the total bits needed for represent the data block. # if necessary, we have to add padding bits to resultant data for # make it fit inside a byte-multiple totbits = 0 for c, count in series: totbits += symb_bits + symbs[c]['rep_bits'] data_pad_bits_count = 8 - (totbits % 8) # pack a byte representing the max bits for every serie (mask 0xF8) and padding bit count (mask 0x7) bp.pack((max_bits_series << 3) | data_pad_bits_count, 8) bits_for_count = bitsForInt(max_bits_series) rep_pad_bits_count = 8 - ((bits_for_count * symbs_count) % 8) # pack the repetition map block if rep_pad_bits_count != 8: bp.pack(0, rep_pad_bits_count) for s in symbs: bp.pack(symbs[s]['rep_bits'], bits_for_max_bits) # pack eventual data padding bits if data_pad_bits_count!=8: bp.pack(0, data_pad_bits_count) # pack the data itself for c,count in series: symb_i= symbs_str.index(c) symb_rep_bits= symbs[c]['rep_bits'] bp.pack( (symb_i<>3)&0x1F data_pad_bits= tmp & 7 # unpack the repetition map bits_for_rep= bitsForInt(serie_max_bits) pad= 8-((symbs_count*bits_for_rep)%8) if pad != 8: bu.unpack(pad) bits_for_symbs= [] for i in range(symbs_count): bits_for_symbs.append(bu.unpack(bits_for_rep)) if data_pad_bits > 0: bu.unpack(data_pad_bits) symb_bits_count = bitsForInt(len(symbs)) out= '' while not bu.eop(): symb_i= bu.unpack(symb_bits_count) count= bu.unpack(bits_for_symbs[symb_i]) + 1 out+= symbs[symb_i] * count return out print('* Some ascii-pics are taked from https://text-symbols.com') print('** Its better view this on PC') print('*** You would not view all ascii-pics because SL server running time limit\n\n') import sys tests ={ 'soloflower': """\n IIIIIIII\n 77 IIIIIIIIIIIII\n ,777 IIIIIIIIIII\n 7777 IIIIIIII %%%%%%%%\n ,7777 IIIIII? %%%%%%%%%%%%%,\n 77777 IIIII ,%%%%%%%%%%%%%%%%%\n 777777 IIII % % %%%%%%%\n 77777I III ooo %%%%%\n 777777 II oooo %%%%\n $ I77777 II oooo? %%%\n $$ 77777, ?oooo %%\n $$7 77777 ooooo \n $$$$ 77777 ? ooooo\n $$$$$ 7777 ?? oooooo\n $$$$$, 77 ??? oooooo\n $$$$$$$, ???? ooooo\n $$$$$$$$$$$$$$$$$$ ????? ooooo\n 7$$$$$$$$$$$$$ ?????? ?oooo\n $$$$$$$% ,??????? ?oooo\n ??;;;;;;;????????? ?oo?\n ??????????????? ?oo\n ????????\n $\n $$\n $?\n $$\n $\n %\n %$\n _,-oo.__ $$\n/oo%%%??%%%\ $\n\%%oooo%%$I%$ $$\n -%%%_%%%/ $ $ __---___ \n %%-

encoder2