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More work with decoding and regenerating P25.

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This commit is contained in:
Jonathan Naylor
2016-09-13 18:27:50 +01:00
parent 30467a749c
commit 0dc1f1bdad
22 changed files with 442 additions and 156 deletions
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48
Hamming.cpp
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@@ -179,6 +179,54 @@ void CHamming::encode1393(bool* d)
d[12] = d[0] ^ d[2] ^ d[4] ^ d[5] ^ d[8];
}
// Hamming (10,6,3) check a boolean data array
bool CHamming::decode1063(bool* d)
{
assert(d != NULL);
// Calculate the checksum this column should have
bool c0 = d[0] ^ d[1] ^ d[2] ^ d[5];
bool c1 = d[0] ^ d[1] ^ d[3] ^ d[5];
bool c2 = d[0] ^ d[2] ^ d[3] ^ d[4];
bool c3 = d[1] ^ d[2] ^ d[3] ^ d[4];
unsigned char n = 0x00U;
n |= (c0 != d[6]) ? 0x01U : 0x00U;
n |= (c1 != d[7]) ? 0x02U : 0x00U;
n |= (c2 != d[8]) ? 0x04U : 0x00U;
n |= (c3 != d[9]) ? 0x08U : 0x00U;
switch (n) {
// Parity bit errors
case 0x01U: d[6] = !d[6]; return true;
case 0x02U: d[7] = !d[7]; return true;
case 0x04U: d[8] = !d[8]; return true;
case 0x08U: d[9] = !d[9]; return true;
// Data bit erros
case 0x07U: d[0] = !d[0]; return true;
case 0x0BU: d[1] = !d[1]; return true;
case 0x0DU: d[2] = !d[2]; return true;
case 0x0EU: d[3] = !d[3]; return true;
case 0x0CU: d[4] = !d[4]; return true;
case 0x03U: d[5] = !d[5]; return true;
// No bit errors
default: return false;
}
}
void CHamming::encode1063(bool* d)
{
assert(d != NULL);
// Calculate the checksum this column should have
d[6] = d[0] ^ d[1] ^ d[2] ^ d[5];
d[7] = d[0] ^ d[1] ^ d[3] ^ d[5];
d[8] = d[0] ^ d[2] ^ d[3] ^ d[4];
d[9] = d[1] ^ d[2] ^ d[3] ^ d[4];
}
// A Hamming (16,11,4) Check
bool CHamming::decode16114(bool* d)
{