with open('target', 'rb') as f:
    target = f.read()
png = ''
i = 0
while i < len(target):
    bitmap = '{0:08b}'.format(ord(target[i]), 'b')
    i += 1
    for bit in bitmap:
        if bit == '0':
            png += target[i]
            i += 1
        else:
            b = '{0:08b}'.format(ord(target[i]), 'b') + '{0:08b}'.format(ord(target[i + 1]), 'b')
            offset = int(b[0:12], 2)
            amount = int(b[12:16], 2)
            png += png[offset: offset + amount]
            i += 2
print ''.join('{:02x}'.format(ord(c)) for c in png)