ECC for BPTC 196,96 working correctly.

RS129.py

@@ -95,32 +95,32 @@ def encode(_msg):
         parity[0] = log_mult(POLY[0], dbyte)
     return [parity[2], parity[1], parity[0]]
 
-# Apply DMR XOR LC start MASK
-def lc_start_mask(_parity):
+# Apply DMR XOR LC Header MASK
+def lc_header_mask(_parity):
     xor = [0,0,0]
     for i in range(len(_parity)):
         xor[i] = _parity[i] ^ START_MASK[i]
     return xor
     
-# Apply DMR XOR LC end MASK
-def lc_end_mask(_parity):
+# Apply DMR XOR LC Terminator MASK
+def lc_terminator_mask(_parity):
     xor = [0,0,0]
     for i in range(len(_parity)):
         xor[i] = _parity[i] ^ END_MASK[i]
     return xor
 
 # All Inclusive function to take an LC string and provide the RS129 string to append
-def lc_start_encode(_message):
+def lc_header_encode(_message):
     bin_message = bytearray(_message)
     parity = encode(bin_message)
-    masked_parity = lc_start_mask(parity)
+    masked_parity = lc_header_mask(parity)
     return chr(masked_parity[0]) + chr(masked_parity[1]) + chr(masked_parity[2])
     
 # All Inclusive function to take an LC string and provide the RS129 string to append
-def lc_end_encode(_message):
+def lc_terminator_encode(_message):
     bin_message = bytearray(_message)
     parity = encode(bin_message)
-    masked_parity = lc_end_mask(parity)
+    masked_parity = lc_terminator_mask(parity)
     return chr(masked_parity[0]) + chr(masked_parity[1]) + chr(masked_parity[2])
     
     
@@ -133,7 +133,10 @@ if __name__ == '__main__':
     
     # Validation Example
     message = '\x00\x10\x20\x00\x0c\x30\x2f\x9b\xe5'
+    message = bytearray(message)
     parity_should_be = '\xda\x4d\x5a'
-    parity = lc_start_encode(message)
+    print('Original Message:            {}'.format(h(message)))
     print('Masked Parity Should be:     {}'.format(h(parity_should_be)))
+    
+    parity = lc_header_encode(message)
     print('Calculated Masked Parity is: {}'.format(h(parity)))

bptc19696.py

@@ -50,20 +50,38 @@ def deinterleave_19696(_data):
 
 # Applies BTPC error detection/correction routines (INCOMPLETE)
 def error_check_19696(_data):
-    errors = False
     count = 0
     column = bitarray(13)
     
     while True:
+        errors = False
         for col in xrange(15):
             pos = col + 1
             for index in xrange(13):
                 column[index] = _data[pos]
                 pos += 15
             
-            if hamming.dec_1393(col)
-        if not errors or count < 5: break
-    return _data
+            result_1393 = hamming.dec_1393(column)
+            if result_1393[1]:
+                pos = col + 1
+                for index in xrange(13):
+                    _data[pos] = result_1393[0][index]
+                    pos += 15
+                errors = True
+                print('fixing error in column {}'.format(col))
+                
+        for index in xrange(9):
+            pos = (index*15) + 1
+            result_15113 = hamming.dec_15113(_data[pos:(pos+15)])
+            if result_15113[1]:
+                errors = True
+                _data[pos:(pos+15)] = result_15113[0]
+                print('fixing error in row {}'.format(index))
+        
+        count += 1
+        print('pass count is {}'.format(count))   
+        if not errors or count > 4: break
+    return (_data, (errors))
     
 # Returns useable LC data - 9 bytes info + 3 bytes RS(12,9) ECC
 def to_bytes_19696(_data):
@@ -87,14 +105,16 @@ if __name__ == '__main__':
     from time import time
 
     # Validation Example
-    data = '\x44\x4d\x52\x44\x00\x2f\x9b\xe5\x00\x0c\x30\x00\x04\xc2\xc4\xa1\xa1\x99\x48\x6e\x2b\x60\x04\x10\x1f\x84\x2d\xd0\x0d\xf0\x7d\x41\x04\x6d\xff\x57\xd7\x5d\xf5\xde\x30\x15\x2e\x20\x70\xb2\x0f\x80\x3f\x88\xc6\x95\xe2\x00\x00'
-    data = data[20:53]
+    data = '\x2b\x60\x04\x10\x1f\x84\x2d\xd0\x0d\xf0\x7d\x41\x04\x6d\xff\x57\xd7\x5d\xf5\xde\x30\x15\x2e\x20\x70\xb2\x0f\x80\x3f\x88\xc6\x95\xe2'
+    data = '\x2b\x60\x04\x10\x1f\x84\x2d\xd0\x0d\xf0\x7d\x41\x04\x6d\xff\x57\xd7\x5d\xf5\xde\x30\x15\x2e\x20\x70\xb2\x0f\x80\x3f\x88\xc6\x95\xe2'
     
     t0 = time()
     bin_data = to_binary_19696(data)
     deint_data = deinterleave_19696(bin_data)
     err_corrected = error_check_19696(deint_data)
-    ext_data = to_bytes_19696(deint_data)
+    if err_corrected[1]:
+        print('WARNING DATA COULD NOT BE CORRECTED')
+    ext_data = to_bytes_19696(err_corrected[0])
     t1 = time()
     print('TIME: ', t1-t0, '\n')
     
@@ -114,6 +134,6 @@ if __name__ == '__main__':
     print(h(deint_data.tobytes()))
     print()
 
-    print('decoded hex data')
-    print(len(ext_data), 'bytes')
-    print(h(ext_data))
+    print('decoded hex data should be: 001020000c302f9be5dad45a')
+    print('decoded data is:           ', h(ext_data))
+    print(len(ext_data), 'bytes')