def add_index(num_oligos,BCH_bits,infile_name,outfile_name):
'''
Generate DNA encoding of all indexes from 0 to num_oligos-1, each protected with BCH_bits protection.
The index DNA strings are appropriately concatenated with corresponding lines from infile_name and the resulting oligos are written to outfile_name, one line per index.
Throw error if num_oligos > 2**24 = 16777216.
'''
if num_oligos > MAX_OLIGOS_NO_RLL:
raise Exception('Too many oligos')
block_len = index_block_len_noRLL
bin_block_len = 2*block_len
if BCH_bits != 0:
bch = bchlib.BCH(BCH_POLYNOMIAL, BCH_bits)
# calculate number of bases used for index
num_bases_BCH = BCH_bits*BCH_bits_per_error/2
num_bases_index = block_len + num_bases_BCH
index = 0
with open(infile_name) as infile, open(outfile_name, 'w') as outfile:
for line in infile:
index_prp = (prp_a*index+prp_b)%MAX_OLIGOS_NO_RLL
bin_string = bin(index_prp)[2:].zfill(bin_block_len)
dna = bin2dna_2bpb(bin_string)
if BCH_bits != 0:
bits_ecc = bytes_to_binary_string(bch.encode(binary_string_to_bytes(bin_string)))
bits_ecc = bits_ecc[:BCH_bits*BCH_bits_per_error]
dna_ecc = bin2dna_2bpb(bits_ecc)
outfile.write(dna+dna_ecc+line)
else:
outfile.write(dna+line)
index += 1
if index == num_oligos:
break
def encode(input_file, output_file, BCH_bits, alpha_raptor):
encode_raptor_script = "./rq --debug encode "
raptor_length = (31-BCH_bits) - (31-BCH_bits)%4 # RaptorQ expects multiples of 4
arg_string = " -s " + str(raptor_length)
arg_string += " -m " + str(1000000)
arg_string += " --repair-symbols-rate " + str(alpha_raptor)
arg_string += " "
arg_string += input_file + " "
arg_string += "tmpfile"
encode_raptor_command = encode_raptor_script + arg_string
subprocess.call([encode_raptor_command], shell=True)
assert os.path.isfile("tmpfile"),"The codebook did not get generated"
bch = bchlib.BCH(BCH_POLYNOMIAL, BCH_bits)
f_input = open("tmpfile", "r");
data = json.load(f_input)
f_input.close()
for i,s in enumerate(data['symbols']):
s_byte = binascii.unhexlify(((hex(int(s[1],2)))[2:-1]).zfill(2*data['symbol_size']))
s_byte_coded = s_byte + bch.encode(s_byte)
data['symbols'][i][1] = bin(int(binascii.hexlify(s_byte_coded), 16))[2:].zfill((data['symbol_size']+BCH_bits)*8)
data['BCH_bits'] = BCH_bits
f_out = open(output_file,'w')
data = json.dumps(data, sort_keys=True, indent=2, separators=(',', ': '))
f_out.write(data)
f_out.close()
def pdf1_to_bch1(pdf1, bch1):
#valid pdf1
binary_data_pdf1 = newdata = pdf1
correctedbch1 = bch1
bch1 = bch1 + '000'
#print('valid pdf1',len(binary_data_pdf1),binary_data_pdf1)
BCH_POLYNOMIAL = 137 #137
BCH_BITS = 3
bitflips = 0
bch = bchlib.BCH(BCH_POLYNOMIAL, BCH_BITS)
data = bytearray(bitstring_to_bytes(binary_data_pdf1))
print('m:', bch.m)
rebuildpdf = ''
for e in range(len(data)):
segment = decodefunctions.dec2bin(data[e]).zfill(8)
rebuildpdf = rebuildpdf + segment
print(e, data[e], segment)
#print(binary_data_pdf1)
print(rebuildpdf, len(rebuildpdf), binary_data_pdf1 == rebuildpdf)
ecc = bch.encode(data)
print(len(ecc))
bchstring = ''
for e in ecc:
binchar = decodefunctions.dec2bin(e)
print(e, binchar)
bchstring = bchstring + binchar
# create array of ecc provide by bch
ecc_provided = bytearray(bitstring_to_bytes(bch1))
packet = data + ecc_provided
bchstr2 = ''
print(len(data), len(ecc), len(packet))
print('ecc included:', ecc_provided, len(ecc_provided), type(ecc_provided))
print('ecc calc:', ecc, len(ecc), type(ecc))
print('match', ecc == ecc_provided)
if ecc != ecc_provided:
#packet = data + ecc
data, ecc = packet[:-bch.ecc_bytes], packet[-bch.ecc_bytes:]
#correct
bitflips = bch.decode_inplace(data, ecc)
print('bitflips: %d' % (bitflips))
newdata = decodefunctions.dec2bin(data[0])
for e in data[1:]:
binchar = decodefunctions.dec2bin(e).zfill(8)
#print(e, binchar)
newdata = newdata + binchar
correctedbch1 = ''
for e in ecc:
binchar = decodefunctions.dec2bin(e).zfill(8)
#print(e, binchar)
correctedbch1 = correctedbch1 + binchar
if (len(correctedbch1)) > 21:
correctedbch1 = correctedbch1[:21]
return (bitflips, newdata, correctedbch1)
def hex_bch(hex):
b = hextobin(hex).zfill(255)
packet = bytearray(bitstring_to_bytes2(b))
bch = bchlib.BCH(487, 6 , False)
data_only, ecc = packet[:-6], packet[-6:] # data, ecc = packet[:-bch.ecc_bytes], packet[-bch.ecc_bytes:]
# correct
corrected_hex =''
bitflips = 0
try:
bitflips = bch.decode_inplace(data_only, ecc)
print('\nbitflips: %d' % (bitflips))
# packetize
packet = data_only + ecc
correct_final=''
for e in packet:
c = dec2bin(e).zfill(8)
correct_final = correct_final + c
corrected_hex = bin2hex(correct_final)
if bitflips:
success = True
else:
success = False
except:
success = False
return (hex,corrected_hex)
def make_full(hexinput):
pdf1 = decodefunctions.hextobin(hexinput)
b = pdf1[:204] + '0' * 48
print(b, len(b))
ecc = calcBCH(b, 0, 202, 250)
newhex = decodefunctions.bin2hex(pdf1[:204] + ecc)
print(newhex)
print(ecc, decodefunctions.bin2hex(ecc))
BCH_POLYNOMIAL = 285 # 285
BCH_BITS = 6
bitflips = 0
bch = bchlib.BCH(BCH_POLYNOMIAL, BCH_BITS)
max_data_len = bch.n // 8 - (bch.ecc_bits + 7) // 8
data = bytearray(bch1correct.bitstring_to_bytes(pdf1[:204]))
necc = bch.encode(data)
bchstring = ''
for e in necc:
binchar = decodefunctions.dec2bin(e).zfill(8)
bchstring = bchstring + binchar
print(bchstring, decodefunctions.bin2hex(bchstring))
newhex = decodefunctions.bin2hex(pdf1[:204] + bchstring)
return newhex
def __init__(self, p, t):
self.bch_polynomial = p
self.bch_bits = t
self.bitflips = 0
# utworzenie obiektu klasy z biblioteki bchlib
self.obj = bchlib.BCH(self.bch_polynomial, self.bch_bits)
def __init__(self, witness_nbits: int, t: int,
extractor: Optional[Callable[[K], BitVector]] = None) -> None:
self.t = t
self.k = witness_nbits
if extractor is None:
extractor = self.byte_extractor
self.extractor = extractor
self.bch = bchlib.BCH(BCH_POLYNOMIAL, self.t)
self.n = self.k + self.bch.ecc_bits # systematic code
def ecc_correct(block, code, ecc_strength):
"""
Try to fix `block` with `code`, for an ECC size of `bitsize`.
"""
ecc = bchlib.BCH(8219, ecc_strength, reverse=True)
try:
block_ = ecc.correct(bytes(block), bytes(code))
return block_
except Exception as e:
return block
def decodeBCH(self, packet):
bch = bchlib.BCH(configBCHPolynomial, configBCHBits)
data, ecc = packet[:-bch.ecc_bytes], packet[-bch.ecc_bytes:]
try:
bitflips, corrected, ecc = bch.decode(data, ecc)
except:
print("Error during decoding!")
return bytearray()
return corrected
def main():
import argparse
parser = argparse.ArgumentParser()
parser.add_argument('model', type=str)
parser.add_argument('--image', type=str, default=None)
parser.add_argument('--images_dir', type=str, default=None)
parser.add_argument('--secret_size', type=int, default=128)
args = parser.parse_args()
if args.image is not None:
files_list = [args.image]
elif args.images_dir is not None:
files_list = glob.glob(args.images_dir + '/*')
else:
print('Missing input image')
return
sess = tf.InteractiveSession(graph=tf.Graph())
model = tf.saved_model.loader.load(sess, [tag_constants.SERVING], args.model)
input_image_name = model.signature_def[signature_constants.DEFAULT_SERVING_SIGNATURE_DEF_KEY].inputs['image'].name
input_image = tf.get_default_graph().get_tensor_by_name(input_image_name)
output_secret_name = model.signature_def[signature_constants.DEFAULT_SERVING_SIGNATURE_DEF_KEY].outputs['decoded'].name
output_secret = tf.get_default_graph().get_tensor_by_name(output_secret_name)
bch = bchlib.BCH(BCH_POLYNOMIAL, BCH_BITS)
for filename in files_list:
image = Image.open(filename).convert("RGB")
image = np.array(ImageOps.fit(image,(512, 512)),dtype=np.float32)
image /= 255.
feed_dict = {input_image:[image]}
secret = sess.run([output_secret],feed_dict=feed_dict)[0][0]
packet_binary = "".join([str(int(bit)) for bit in secret])
packet = bytes(int(packet_binary[i : i + 8], 2) for i in range(0, len(packet_binary), 8))
packet = bytearray(packet)
data, ecc = packet[:-bch.ecc_bytes], packet[-bch.ecc_bytes:]
print(data)
print(ecc)
bitflips = bch.decode_inplace(data, ecc)
if bitflips != -1:
try:
code = data.decode("utf-8")
print(filename, code)
continue
except:
continue
print(filename, 'Failed to decode')
def encryptBCH(selfself, array):
polynomial = 8219
t = 2
bch = bchlib.BCH(polynomial, t)
data = bytearray(array)
code = bch.encode(data)
result = data + code
result = list(result)
return result
def encode(self, input_raw_frames, asecret):
width = FrameSize.WIDTH.value
height = FrameSize.HEIGHT.value
bch = bchlib.BCH(BCH_POLYNOMIAL, BCH_BITS)
if len(asecret) > 7:
print('Error: Can only encode 56bits (7 characters) with ECC')
return
data = bytearray(asecret + ' ' * (7 - len(asecret)), 'utf-8')
ecc = bch.encode(data)
packet = data + ecc
packet_binary = ''.join(format(x, '08b') for x in packet)
secret = [int(x) for x in packet_binary]
secret.extend([0, 0, 0, 0])
encoded_frames = []
residual_frames = []
# the input frame has already been set to RGB
for image in input_raw_frames:
# image = cv2.imread(frame)
# image = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
image = cv2.resize(image, (width, height))
image = image.astype(np.float32)
image /= 255.
feed_dict = {
self.encode_input_secret: [secret],
self.encode_input_image: [image]
}
hidden_img, residual = self.encode_sess.run(
[self.encode_output_stegastamp, self.encode_output_residual],
feed_dict=feed_dict)
rescaled = (hidden_img[0] * 255).astype(np.uint8)
encoded_frame = cv2.cvtColor(np.asarray(rescaled),
cv2.COLOR_RGB2BGR)
encoded_frames.append(encoded_frame)
# get the residual image
residual = residual[0] + .5
residual = (residual * 255).astype(np.uint8)
residual = cv2.cvtColor(np.squeeze(np.array(residual)),
cv2.COLOR_BGR2RGB)
residual_frames.append(residual)
if self.return_residual is True:
return encoded_frames, residual_frames
else:
return encoded_frames
def performBCHCorrection(extractedPacket):
bch = bchlib.BCH(BCH_POLYNOMIAL, BCH_BITS)
newData, newEcc = extractedPacket[:-bch.ecc_bytes], extractedPacket[
-bch.ecc_bytes:]
try:
bitflips = bch.decode_inplace(newData, newEcc)
#print('bitflips: %d' % (bitflips))
#print("Here is the decrypted message: ", newData.decode('utf-8'))
return newData.decode('utf-8').rstrip(' \n')
except:
#print("Issues with decoding data, here's what was recovered: ", newData)
return newData
def setupBCH(msg):
# create a bch object
bch = bchlib.BCH(BCH_POLYNOMIAL, BCH_BITS)
data = bytearray()
data.extend(map(ord, msg))
ecc = bch.encode(data)
packet = data + ecc
binPacket = ""
for i in range(0, len(packet)):
binPacket += '{0:08b}'.format(packet[i])
# binPacket += " "
return binPacket
def decode_data(infile,oligo_length,outfile,BCH_bits,LDPC_alpha,LDPC_prefix,file_size, eps, mode = 'correct', MSA=False, sync='',sync_pos=-1):
'''
Decoder corresponding to encoder encode_data. Need same parameters as that.
infile is file containing reads of the same length as the oligo_length.
Returns status - 0 for success, 1 for failure
In case of success, resulting decoded file is written to outfile.
file_size is the size of the original file in bytes.
mode is correct or detect as in remove_index
eps is the error to be used in LDPC LLR
'''
data_len = 8*file_size
decoded_data = []
# NEW
# calculate various parameters for encoding
num_LDPC_blocks = int(math.ceil(1.0*data_len/LDPC_dim))
parity_bits_per_LDPC_block = int(LDPC_alpha*LDPC_dim)
if BCH_bits != 0:
bch = bchlib.BCH(BCH_POLYNOMIAL, BCH_bits)
# calculate number of bases used for index
num_bases_BCH = BCH_bits*BCH_bits_per_error/2
num_bases_index = index_block_len_noRLL + num_bases_BCH
else:
num_bases_index = index_block_len_noRLL
oligo_length_before_sync = oligo_length - len(sync)
num_bases_payload = oligo_length_before_sync - num_bases_index
bits_per_oligo = num_bases_payload*2
num_oligos_data_per_LDPC_block = int(math.ceil(1.0*LDPC_dim/(bits_per_oligo)))
num_oligos_parity_per_LDPC_block = int(math.ceil(1.0*parity_bits_per_LDPC_block/bits_per_oligo))
num_oligos_per_LDPC_block = num_oligos_data_per_LDPC_block+num_oligos_parity_per_LDPC_block
overall_rate = 1.0*data_len/(num_oligos_per_LDPC_block*num_LDPC_blocks*oligo_length)
print 'overall rate:' ,overall_rate, 'bpb'
print 'num oligos:', num_LDPC_blocks*num_oligos_per_LDPC_block
print 'oligo length:', oligo_length, 'bases'
print 'bases per oligo for index + index parity:', num_bases_index
print 'fraction of oligos used for parity check:', 1.0*num_oligos_parity_per_LDPC_block/num_oligos_per_LDPC_block
print 'number of LDPC blocks:', num_LDPC_blocks
# find positions of parity bits in LDPC encoded file
f_sys = open(LDPC_prefix+".systematic",'r')
sys_pos = f_sys.readlines()
f_sys.close()
sys_pos = np.array([int(i) for i in sys_pos])
mask = np.zeros(parity_bits_per_LDPC_block+LDPC_dim,dtype=bool)
mask[sys_pos] = True
mask = ~mask
parity_pos = np.nonzero(mask)[0]
tmp_index_file = infile+'.tmp.index'
tmp_data_file = infile+'.tmp.data'
def samplepdf2(f, r):
for n in range(r):
pdf2 = randombinary(26).zfill(26)
bch2 = Fcn.calcbch('0' * 107 + pdf2, '1010100111001', 107, 133,
145) + '0000'
bch = bchlib.BCH(67, 2)
data = bytearray(bch1correct.bitstring_to_bytes(pdf2))
ecc = bch.encode(data)
bchstring = (Fcn.dec2bin(ecc[0]).zfill(8) +
Fcn.dec2bin(ecc[1]).zfill(8))[:12] + '0000'
e = random.sample(range(0, 38), 3)
scramble = list(pdf2 + bch2)
for i in e:
scramble[i] = str(int(not int(scramble[i])))
corrupt = ''.join(scramble)
ecc_provided = bytearray(bch1correct.bitstring_to_bytes(corrupt[26:]))
data_provided = bytearray(bch1correct.bitstring_to_bytes(corrupt[:26]))
ecc_c = bch.encode(data_provided)
print(ecc_c == ecc_provided, ecc, ecc_provided)
packet = bytearray(bch1correct.bitstring_to_bytes(
corrupt[:26])) + bytearray(
bch1correct.bitstring_to_bytes(corrupt[26:]))
data, ecc = packet[:-bch.ecc_bytes], packet[-bch.ecc_bytes:]
bitflips = bch.decode_inplace(data, ecc)
newdata = Fcn.dec2bin(data[0]).zfill(2)
for e in data[1:]:
binchar = Fcn.dec2bin(e).zfill(8)
newdata = newdata + binchar
correctedbch2 = '' # decodefunctions.dec2bin(ecc[0])
for e in ecc:
binchar = Fcn.dec2bin(e).zfill(8)
correctedbch2 = correctedbch2 + binchar
correctedbch2 = correctedbch2[:-4]
bch2 = bch2[:-4]
bchstring = bchstring[:-4]
f.writelines([
'{},{},{},{},{},{},{},{}'.format(
pdf2 + bch2, bch2 == bchstring, corrupt, len(pdf2 + bch2),
corrupt == pdf2 + bch2, newdata + correctedbch2,
newdata + correctedbch2 == pdf2 + bch2, bitflips), '\n'
])
def main():
import argparse
parser = argparse.ArgumentParser()
parser.add_argument('model', type=str)
parser.add_argument('--image', type=str, default=None)
parser.add_argument('--images_dir', type=str, default=None)
parser.add_argument('--secret_size', type=int, default=100)
args = parser.parse_args()
if args.image is not None:
files_list = [args.image]
elif args.images_dir is not None:
files_list = glob.glob(args.images_dir + '/*')
else:
print('Missing input image')
return
decoder = torch.load(args.model)
bch = bchlib.BCH(BCH_POLYNOMIAL, BCH_BITS)
for filename in files_list:
image = Image.open(filename).convert("RGB")
image = np.array(ImageOps.fit(image, (400, 400)), dtype=np.float32)
image /= 255.
secret = decoder(image)
packet_binary = "".join([str(int(bit)) for bit in secret[:96]])
packet = bytes(
int(packet_binary[i:i + 8], 2)
for i in range(0, len(packet_binary), 8))
packet = bytearray(packet)
data, ecc = packet[:-bch.ecc_bytes], packet[-bch.ecc_bytes:]
bitflips = bch.decode_inplace(data, ecc)
if bitflips != -1:
try:
code = data.decode("utf-8")
print(filename, code)
continue
except:
continue
print(filename, 'Failed to decode')
def decodeBCH(self, array):
polynomial = 8219
t = 2
bch = bchlib.BCH(polynomial, t)
data, code = array[:-bch.ecc_bytes], array[-bch.ecc_bytes:]
data = bytearray(data)
code = bytearray(code)
flips, data, code = bch.decode(data, code)
data = list(data)
print("Odkodowana wiadomość: ")
if flips is -1:
self.analysis.addAmount(0, 1, 0)
elif flips > 0:
self.analysis.addAmount(0, 0, 1)
elif flips is 0:
self.analysis.addAmount(1, 0, 0)
print(data)
def decode(input_file, recon_file):
decode_raptor_script = "../python-libraptorq/rq --debug decode "
f_input = open(input_file, "r")
data = json.load(f_input)
f_input.close()
bch = bchlib.BCH(BCH_POLYNOMIAL, data['BCH_bits'])
reads_dict = {}
num_bytes_per_read = len(data['symbols'][0][1]) // 8
# load reads and store according to index
for read in data['symbols']:
if read[0] in reads_dict:
reads_dict[read[0]].append([int(c) for c in read[1]])
else:
reads_dict[read[0]] = [[int(c) for c in read[1]]]
corrected_reads = [] #to store index and corrected bitstring
bitflips_dict = {
} #to store the number of bitflips for each index (for sorting later)
# convert to numpy arrays, find consensus, do BCH decoding and keep if decoding successful
for k in reads_dict.keys():
read_array = np.array(reads_dict[k], dtype=int)
majority_list = np.array(np.mean(read_array, axis=0) > 0.5, dtype=int)
majority_str = ''.join([str(c) for c in majority_list])
majority_str_bytes = binascii.unhexlify(
((hex(int(majority_str,
2)))[2:-1]).zfill(2 * (num_bytes_per_read)))
maj_data, maj_ecc = majority_str_bytes[:-bch.
ecc_bytes], majority_str_bytes[
-bch.ecc_bytes:]
(bitflips, maj_data, maj_ecc) = bch.decode(maj_data, maj_ecc)
if bitflips >= 0: #success
corrected_str = base64.urlsafe_b64encode(maj_data)
corrected_reads.append([k, corrected_str])
bitflips_dict[k] = bitflips
corrected_reads.sort(key=lambda x: bitflips_dict[x[0]])
output_data = dict(data)
output_data['symbols'] = corrected_reads
f_intermediate = open("tmpfile", "w")
f_intermediate.write(
json.dumps(output_data,
sort_keys='False',
indent=2,
separators=(',', ': ')))
f_intermediate.close()
ret = subprocess.call([decode_raptor_script + " tmpfile " + recon_file],
shell=True)
return ret
def __init__(self,
witness_nbits: int,
tolerance: int,
extractor: Optional[Callable[[K], BitVector]] = None,
polynomial: int = BCH_POLYNOMIAL) -> None:
"""Initializes FCS.
Args:
witness_nbits: Length of the witness in bits.
tolerance: Number of changed bits tolerated by the scheme.
extractor: Optional function to extract a BitVector from K.
polynomial: Optional polynomial for the BCH code (see bchlib).
"""
self._witlen = witness_nbits
if extractor is None:
extractor = _byte_extractor
self._extractor = extractor
self._bch = bchlib.BCH(polynomial, tolerance)
def test_bchlib():
# create a bch object
BCH_POLYNOMIAL = 8219
BCH_BITS = 16
bch = bchlib.BCH(BCH_POLYNOMIAL, BCH_BITS)
# random data
data = bytearray(os.urandom(512))
# encode and make a "packet"
ecc = bch.encode(data)
packet = data + ecc
# print hash of packet
sha1_initial = hashlib.sha1(packet)
def bitflip(packet):
byte_num = random.randint(0, len(packet) - 1)
bit_num = random.randint(0, 7)
packet[byte_num] ^= (1 << bit_num)
# make BCH_BITS errors
for _ in range(BCH_BITS):
bitflip(packet)
# print hash of packet
sha1_corrupt = hashlib.sha1(packet)
# de-packetize
data, ecc = packet[:-bch.ecc_bytes], packet[-bch.ecc_bytes:]
# correct
bitflips = bch.decode_inplace(data, ecc)
# packetize
packet = data + ecc
# print hash of packet
sha1_corrected = hashlib.sha1(packet)
assert sha1_initial.digest() == sha1_corrected.digest()
def decode(input_file, recon_file):
decode_raptor_script = "./rq --debug decode "
f_input = open(input_file, "r");
data = json.load(f_input)
f_input.close()
bch = bchlib.BCH(BCH_POLYNOMIAL, data['BCH_bits'])
corrected_reads = []
# put corrected reads into corrected reads and drop non-corrected reads (no consensus)
for read in data['symbols']:
read_bytes = binascii.unhexlify(((hex(int(read[1],2)))[2:-1]).zfill(2*(data['symbol_size']+data['BCH_bits'])))
read_data,read_ecc = read_bytes[:-bch.ecc_bytes], read_bytes[-bch.ecc_bytes:]
(bitflips, read_data, read_ecc) = bch.decode(read_data, read_ecc)
if bitflips >= 0: #success
corrected_str = bin(int(binascii.hexlify(read_data), 16))[2:].zfill(data['symbol_size']*8)
corrected_reads.append([read[0], corrected_str])
output_data = dict(data)
output_data['symbols'] = corrected_reads
f_intermediate = open("tmpfile", "w");
f_intermediate.write(json.dumps(output_data, sort_keys = 'False', indent=2, separators=(',', ': ')))
f_intermediate.close()
ret = subprocess.call([decode_raptor_script+" tmpfile "+ recon_file], shell=True)
return ret
def add_index(num_oligos, BCH_bits, infile_name, outfile_name, bin_index_len):
'''
Generate DNA encoding of all indexes from 0 to num_oligos-1, each protected with BCH_bits protection.
The index DNA strings are appropriately concatenated with corresponding lines from infile_name and the resulting oligos are written to outfile_name, one line per index.
Throw error if num_oligos > 2**index_len.
'''
if bin_index_len not in prp_a:
raise Exception('Invalid index_len (see prp_a dict for valid options)')
MAX_OLIGOS = 2**bin_index_len
if num_oligos > MAX_OLIGOS:
raise Exception('Too many oligos for index len')
num_bytes_BCH_input = math.ceil(bin_index_len / 8)
if BCH_bits != 0:
bch = bchlib.BCH(BCH_POLYNOMIAL, BCH_bits)
index = 0
with open(infile_name) as infile, open(outfile_name, 'w') as outfile:
for line in infile:
index_prp = (prp_a[bin_index_len] * index +
prp_b[bin_index_len]) % MAX_OLIGOS
bin_string = bin(index_prp)[2:].zfill(bin_index_len)
dna = bin2dna_2bpb(bin_string)
if BCH_bits != 0:
bits_ecc = bytes_to_binary_string(
bch.encode(
binary_string_to_bytes(
bin_string.zfill(8 * num_bytes_BCH_input))))
bits_ecc = bits_ecc[:BCH_bits * BCH_bits_per_error]
dna_ecc = bin2dna_2bpb(bits_ecc)
outfile.write(dna + dna_ecc + line)
else:
outfile.write(dna + line)
index += 1
if index == num_oligos:
break
def main():
# Initializing network
config = tf.ConfigProto()
config.gpu_options.allow_growth = True
detector_graph = tf.Graph()
decoder_graph = tf.Graph()
with detector_graph.as_default():
detector_sess = tf.Session()
detector_model = tf.saved_model.loader.load(detector_sess,
[tag_constants.SERVING],
args.detector_model)
detector_input_name = detector_model.signature_def[
signature_constants.
DEFAULT_SERVING_SIGNATURE_DEF_KEY].inputs['image'].name
detector_input = detector_graph.get_tensor_by_name(detector_input_name)
detector_output_name = detector_model.signature_def[
signature_constants.
DEFAULT_SERVING_SIGNATURE_DEF_KEY].outputs['detections'].name
detector_output = detector_graph.get_tensor_by_name(
detector_output_name)
with decoder_graph.as_default():
decoder_sess = tf.Session()
decoder_model = tf.saved_model.loader.load(decoder_sess,
[tag_constants.SERVING],
args.decoder_model)
decoder_input_name = decoder_model.signature_def[
signature_constants.
DEFAULT_SERVING_SIGNATURE_DEF_KEY].inputs['image'].name
decoder_input = decoder_graph.get_tensor_by_name(decoder_input_name)
decoder_output_name = decoder_model.signature_def[
signature_constants.
DEFAULT_SERVING_SIGNATURE_DEF_KEY].outputs['decoded'].name
decoder_output = decoder_graph.get_tensor_by_name(decoder_output_name)
cap = cv2.VideoCapture(args.video)
bch = bchlib.BCH(BCH_POLYNOMIAL, BCH_BITS)
if args.save_video is not None:
ret, frame = cap.read()
fourcc1 = cv2.VideoWriter_fourcc(*'XVID')
out = cv2.VideoWriter(args.save_video, fourcc1, 30.0, (1920, 1080))
while (True):
ret, frame = cap.read()
if frame is None:
break
frame_rgb = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
detector_image_input = cv2.resize(frame_rgb, (1024, 1024))
detector_image_input = np.expand_dims(np.float32(detector_image_input),
axis=0) / 255.0
output_image = detector_sess.run(
detector_output, feed_dict={detector_input: detector_image_input})
output_image = np.array(output_image[0, :, :, :])
output_image = x = np.argmax(output_image, axis=-1)
color_codes = np.array([[255, 255, 255], [0, 0, 0]])
out_vis_image = color_codes[output_image.astype(int)]
mask_im = cv2.resize(np.float32(out_vis_image), (1920, 1080))
contours, _ = cv2.findContours(
cv2.cvtColor(mask_im, cv2.COLOR_BGR2GRAY).astype(np.uint8), 1, 2)
extrema = np.zeros((8, 2))
corners = np.zeros((4, 2))
for cnt in contours:
area = cv2.contourArea(cnt)
if area < 1000:
continue
hull = cv2.convexHull(cnt)
if len(hull) < 4:
continue
extrema[0, :] = hull[np.argmax(hull[:, 0, 0]), 0, :]
extrema[1, :] = hull[np.argmax(hull[:, 0, 0] + hull[:, 0, 1]),
0, :]
extrema[2, :] = hull[np.argmax(hull[:, 0, 1]), 0, :]
extrema[3, :] = hull[np.argmax(-hull[:, 0, 0] + hull[:, 0, 1]),
0, :]
extrema[4, :] = hull[np.argmax(-hull[:, 0, 0]), 0, :]
extrema[5, :] = hull[np.argmax(-hull[:, 0, 0] - hull[:, 0, 1]),
0, :]
extrema[6, :] = hull[np.argmax(-hull[:, 0, 1]), 0, :]
extrema[7, :] = hull[np.argmax(hull[:, 0, 0] - hull[:, 0, 1]),
0, :]
extrema_lines = extrema - np.roll(extrema, shift=1, axis=0)
extrema_len = extrema_lines[:, 0]**2 + extrema_lines[:, 1]**2
line_idx = np.sort(extrema_len.argsort()[-4:])
for c in range(4):
p1 = extrema[line_idx[(c - 1) % 4], :]
p2 = extrema[(line_idx[(c - 1) % 4] - 1) % 8, :]
p3 = extrema[line_idx[c], :]
p4 = extrema[(line_idx[c] - 1) % 8, :]
corners[c, :] = get_intersect(p1, p2, p3, p4)
new_area = poly_area(corners)
if new_area / area > 1.5:
continue
corners = order_points(corners)
corners_full_res = corners
pts_dst = np.array([[0, 0], [399, 0], [399, 399], [0, 399]])
h, status = cv2.findHomography(corners_full_res, pts_dst)
try:
warped_im = cv2.warpPerspective(frame_rgb, h, (400, 400))
w_im = warped_im.astype(np.float32)
w_im /= 255.
except:
continue
for im_rotation in range(4):
w_rotated = np.rot90(w_im, im_rotation)
recovered_secret = decoder_sess.run(
[decoder_output], feed_dict={decoder_input:
[w_rotated]})[0][0]
recovered_secret = list(recovered_secret)
recovered_secret = [int(i) for i in recovered_secret]
packet_binary = "".join(
[str(bit) for bit in recovered_secret[:96]])
footer = recovered_secret[96:]
if np.sum(footer) > 0:
continue
packet = bytes(
int(packet_binary[i:i + 8], 2)
for i in range(0, len(packet_binary), 8))
packet = bytearray(packet)
data, ecc = packet[:-bch.ecc_bytes], packet[-bch.ecc_bytes:]
bitflips = bch.decode_inplace(data, ecc)
if bitflips != -1:
print('Num bits corrected: ', bitflips)
try:
code = data.decode("utf-8")
except:
continue
color = (100, 250, 100)
cv2.polylines(frame,
np.int32([corners]),
thickness=6,
color=color,
isClosed=True)
font = cv2.FONT_HERSHEY_SIMPLEX
im = cv2.putText(
frame, code,
tuple((corners[0, :] + np.array([0, -15])).astype(
np.int)), font, 1, (0, 0, 0), 2, cv2.LINE_AA)
if args.save_video is not None:
out.write(frame)
else:
cv2.imshow('frame', frame)
cv2.waitKey(1)
cap.release()
if args.save_video:
out.release()
def remove_index(num_oligos,
BCH_bits,
infile_name,
outfile_data,
outfile_index,
bin_index_len,
attempt_indel_cor=True):
'''
Decode index from a collection of (noisy) reads in infile_name and write data and index to outfile_data and outfile_index, line by line, skipping positions where index failed to decode.
attempt_indel_cor: if substitution decoding fails, try to decode indel by trying positions one by one (first do deletion, if exactly one possibility, good otherwise also try insertions).
'''
max_bitflips_sub = BCH_bits
max_bitflips_indel = 0
if bin_index_len not in prp_a:
raise Exception('Invalid index_len (see prp_a dict for valid options)')
MAX_OLIGOS = 2**bin_index_len
if num_oligos > MAX_OLIGOS:
raise Exception('Too many oligos for index len')
dna_index_len = bin_index_len // 2
num_bytes_BCH_input = math.ceil(bin_index_len / 8)
if BCH_bits != 0:
bch = bchlib.BCH(BCH_POLYNOMIAL, BCH_bits)
# calculate number of bases used for index
num_bases_BCH = BCH_bits * BCH_bits_per_error // 2
num_bases_index = dna_index_len + num_bases_BCH
else:
num_bases_index = dna_index_len
count_success = 0
count_indel_corrected = 0
count_failed = 0
with open(infile_name) as infile, open(outfile_data, 'w') as f_data, open(
outfile_index, 'w') as f_index:
for line in infile:
dna_data = line[num_bases_index:]
dna_index = line[:num_bases_index]
if BCH_bits != 0:
successful_indices = []
indel_corrected = False
# first try direct decoding with substitutions
(bitflips, cor_index,
cor_ecc) = decode_index_BCH(dna_index, num_bases_BCH,
BCH_bits, num_bytes_BCH_input,
bch)
if bitflips >= 0 and bitflips <= max_bitflips_sub:
index = decode_index_prp(cor_index, bin_index_len,
prp_a_inv[bin_index_len],
prp_b[bin_index_len], MAX_OLIGOS)
if index < num_oligos:
successful_indices.append((index, dna_data))
if len(successful_indices) == 0 and attempt_indel_cor:
# indel correction mode
# try to correct 1 deletion by inserting each base at each possible position
# and try BCH decoding with at most max_bitflips_indel errors
indel_corrected = True
dna_index = line[:num_bases_index - 1]
for pos in range(num_bases_index):
for new_base in ['A', 'C', 'G', 'T']:
new_dna_index = dna_index[:pos] + \
new_base+dna_index[pos:]
(bitflips, cor_index, cor_ecc) = decode_index_BCH(
new_dna_index, num_bases_BCH, BCH_bits,
num_bytes_BCH_input, bch)
if bitflips >= 0 and bitflips <= max_bitflips_indel:
index = decode_index_prp(
cor_index, bin_index_len,
prp_a_inv[bin_index_len],
prp_b[bin_index_len], MAX_OLIGOS)
if index < num_oligos:
successful_indices.append(
(index, line[num_bases_index - 1:]))
if len(successful_indices) > 1:
break # fail
if len(successful_indices) == 0:
# try insertion (i.e., delete positions one by one and see if it satisfies BCH w/o error)
dna_index = line[:num_bases_index + 1]
for pos in range(num_bases_index):
new_dna_index = dna_index[:pos] + \
dna_index[pos+1:]
(bitflips, cor_index, cor_ecc) = decode_index_BCH(
new_dna_index, num_bases_BCH, BCH_bits,
num_bytes_BCH_input, bch)
if bitflips >= 0 and bitflips <= max_bitflips_indel:
index = decode_index_prp(
cor_index, bin_index_len,
prp_a_inv[bin_index_len],
prp_b[bin_index_len], MAX_OLIGOS)
if index < num_oligos:
successful_indices.append(
(index, line[num_bases_index + 1:]))
if len(successful_indices) > 1:
break # fail
# succeed if exactly one successful decoding
if len(successful_indices) == 1:
f_data.write(successful_indices[0][1])
f_index.write(str(successful_indices[0][0]) + '\n')
count_success += 1
if indel_corrected:
count_indel_corrected += 1
else:
count_failed += 1
else:
bin_index = dna2bin_2bpb(dna_index)
index_prp = int(bin_index, 2)
index = (prp_a_inv[bin_index_len] *
(index_prp - prp_b[bin_index_len])) % MAX_OLIGOS
if index < num_oligos:
f_data.write(dna_data)
f_index.write(str(index) + '\n')
count_success += 1
else:
count_failed += 1
print("Successfully decoded", count_success, "indices")
print("Deletion corrected", count_indel_corrected)
print("Failed to decode", count_failed, "indices")
def crc(data, pol, bits):
bch = bchlib.BCH(pol, bits)
return bch.encode(data)
def get_instance(ecc_strength):
if BCH.instance is None:
BCH.instance = bchlib.BCH(8219, ecc_strength, reverse=True)
return BCH.instance
import bchlib
import hashlib
import os
import random
from reedsolo import RSCodec
from bitstring import BitArray
# create a bch object
BCH_POLYNOMIAL = 8219
BCH_BITS = 16
bch = bchlib.BCH(BCH_POLYNOMIAL, BCH_BITS)
error_chance = 0.01
errors = 0
def chunk(l, chunk_size):
return [l[i:i + chunk_size] for i in range(0, len(l), chunk_size)]
def compare(a, b):
correct = 0
for i in range(len(a)):
if a[i] == b[i]:
correct = correct + 1
return correct
# BCH
def bchEncode(data):
ecc = bch.encode(data)
# Installation :
# python -m pip install bchlib
import bchlib
import hashlib
import os
import random
# on créer un objet BCH, le polynome est un polynome primitif du champ de Galois de 2 puissance 13,14 ou 15
# https://link.springer.com/content/pdf/bbm%3A978-1-4615-1509-8%2F1.pdf
BCH_POLYNOME = 16659
# nombre de bits que l'on va changer pour mettre des erreurs
BCH_BITS = 50
bch = bchlib.BCH(BCH_POLYNOME, BCH_BITS)
# données aléatoires
data = bytearray(os.urandom(512))
# encodage dans un paquet
ecc = bch.encode(data)
paquet = data + ecc
# affichage du hash du paquet
sha1_initial = hashlib.sha1(paquet)
print('sha1: %s' % (sha1_initial.hexdigest(),))
"""Fonction pour ajouter aléatoirement des erreurs dans notre paquet"""
def bitflip(paquet):
byte_num = random.randint(0, len(paquet) - 1)
bit_num = random.randint(0, 7)
paquet[byte_num] ^= (1 << bit_num)
def atmel_generate_ecc_data(infile, outfile, config, crypto_key):
"""Generate ECC data and resulting dump file for ATMEL"""
# initialize BCH encoder
bch = bchlib.BCH(config['ecc_polynom'], config['ecc_errors'], False)
# open output file
fout = open(outfile, "wb")
# open input file
fin = open(infile, "rb")
# initialize some variables
processed_sector_count = 0
data_sector_count = 0
blank_page_count = 0
total_page_count = config['filesize'] // config['pagesize']
sectors_per_page = config['pagesize'] // config['sectorsize']
total_sectors = total_page_count * sectors_per_page
ecc_bytes_total = sectors_per_page * config['ecc_bytes_per_sector']
# blank page data
blank_page = b'\xff' * config['pagesize']
# blank spare area data
blank_spare_area = b'\xff' * config['spareareasize']
# spare bytes before and after ECC data
spare_area1 = b'\xff' * config['ecc_offset']
spare_area2 = b'\xff' * (config['spareareasize'] - config['ecc_offset'] -
ecc_bytes_total)
print("[*] Generating output file ...")
for page in range(total_page_count):
# read current block data
page_data = fin.read(config['pagesize'])
processed_sector_count += sectors_per_page
if page_data == blank_page:
# increment blank page counter
blank_page_count += 1
# write blank page data and blank spare area data
fout.write(page_data + blank_spare_area)
else:
# increment data sector counter
data_sector_count += sectors_per_page
# generate ECC for each sector
eccs = b''
for sector in range(sectors_per_page):
start_sector = sector * config['sectorsize']
end_sector = start_sector + config['sectorsize']
sector_data = reverse_bits(page_data[start_sector:end_sector])
ecc = bch.encode(sector_data)
# encrypt ECC
# key = unhexlify("F78A7490B7C95943E99EA724AD")
ecc_encrypted = xor_crypto(reverse_bits(ecc), crypto_key)
eccs += ecc_encrypted
# eccs += reverse_bits(ecc_encrypted)
spare_area_data = spare_area1 + eccs + spare_area2
fout.write(page_data + spare_area_data)
# show some statistics during processing all sectors
progress = processed_sector_count / total_sectors * 100
print("\r Progress: {:.2f}% ({}/{} sectors)".format(
progress, processed_sector_count, total_sectors),
end="")
# close output file
fout.close()
# close input file
fin.close()
# show some statistics at the end
blank_page_percentage = blank_page_count / total_page_count * 100
blank_sector_count = blank_page_count * sectors_per_page
blank_sector_percentage = blank_sector_count / total_sectors * 100
data_sector_percentage = data_sector_count / total_sectors * 100
bad_block_count = 0
print("\n[*] Completed error correcting process")
print(
" Successfully written {} bytes of data to output file '{}'".format(
config['sectorsize'] * total_sectors, outfile))
print(" -----\n Some statistics\n"
" Total pages: {}\n"
" Blank pages: {} ({:.2f}%)\n"
" Blank sectors: {} ({:.2f}%)\n"
" Data sectors: {} ({:.2f}%)\n"
" Total sectors: {}\n"
" Bad blocks: {}".format(
total_page_count, blank_page_count, blank_page_percentage,
blank_sector_count, blank_sector_percentage, data_sector_count,
data_sector_percentage, total_sectors, bad_block_count))