void testPunctureUnpuncture(const char *label, const unsigned int *punk, size_t plth)
{
bool ok = true;
// Things could go wrong and be missed due to we're just wrangling bit vectors,
// so run each speed a few times to reduce the probability of missing an error.
for (int i = 0; i < 5; i++) {
// generate orig
BitVector orig = randomBitVector(448+plth);
// puncture
BitVector punctured(orig.size() - plth);
orig.copyPunctured(punctured, punk, plth);
SoftVector softPunctured(punctured);
// unpuncture
SoftVector unpunctured(orig.size());
softPunctured.copyUnPunctured(unpunctured, punk, plth);
// verify
const unsigned *p = punk;
for (unsigned i = 0; i < orig.size(); i++) {
if (unpunctured[i] == 0.5) {
if (*p++ != i) ok = false;
} else {
if (orig.bit(i) != unpunctured[i]) ok = false;
}
}
ok = ok && (p == punk + plth);
}
cout << "puncture->unpuncture " << label << " " << (ok ? "ok" : "NOT ok") << endl;
}
static void printdiff(BitVector &v1, BitVector &v2)
{
int diffbit, v1size = v1.size();
for (diffbit=0; diffbit < v1size; diffbit++) {
if (v1.bit(diffbit) != v2.bit(diffbit)) { break; }
}
if (diffbit < v1size) {
//printf("vectors size %d differ at bit %d\n",v1.size(),diffbit);
//printf("1= %s\n",v1.hexstr().c_str());
//printf("2= %s\n",v2.hexstr().c_str());
printf("d=");
for (int i = 0; i < v1size; i++) {
if (v1.bit(i) != v2.bit(i)) {
printf("%c", '0' + v1.bit(i));
} else {
printf("-");
}
}
printf("\n");
}
}
void print(io::Output& out, const BitVector& v) {
t::uint32 w = 0;
int c = 0;
for(int i = 0; i < v.size(); i++) {
if(v.bit(i))
w |= 1 << c;
c++;
if(c == 31) {
out << ' ' << io::hex(w).width(8).pad('0').right();
w = 0;
c = 0;
}
}
if(c)
out << ' ' << io::hex(w).width(8).pad('0').right();
}
// Return true if we send a block on the downlink.
bool PDCHL1Downlink::send1DataFrame( //SVGDBG
RLCDownEngine *engdown,
RLCDownlinkDataBlock *block, // block to send.
int makeres, // 0 = no res, 1 = optional res, 2 = required res.
MsgTransactionType mttype, // Type of reservation
unsigned *pcounter)
{
//ScopedLock lock(testlock);
TBF *tbf = engdown->getTBF();
if (! setMACFields(block,mchParent,tbf,makeres,mttype,pcounter)) { return false; }
// The rest of the RLC header is already set, but we did not know the tfi
// when we created the RLCDownlinkDataBlocks (because tbf not yet attached)
// so set tfi now that we know. Update 8-2012: Above comment is stale because we
// make the RLCDownlinkBlocks on the fly now.
block->mTFI = tbf->mtTFI;
// block->mPR = 1; // DEBUG test; made no diff.
tbf->talkedDown();
BitVector tobits = block->getBitVector(); // tobits deallocated when this function exits.
if (block->mChannelCoding == 0) { devassert(tobits.size() == 184); }
if (GPRSDebug & 1) {
RLCBlockReservation *res = mchParent->getReservation(gBSNNext);
std::ostringstream sshdr;
block->text(sshdr,false); //block->RLCDownlinkDataBlockHeader::text(sshdr);
ByteVector content(tobits);
GPRSLOG(1) << "send1DataFrame "<<parent()<<" "<<tbf<<LOGVAR(tbf->mtExpectedAckBSN)
<< " "<<sshdr.str()
<<" "<<(res ? res->str() : "")
<< LOGVAR2("content",content);
//<< " enc="<<tbf->mtChannelCoding <<" "<<os.str() << "\nbits:" <<bits.str();
//<<" " <<block->str() <<"\nbits:" <<tobits.hexstr();
}
#if FEC_DEBUG
BitVector copybits; copybits.clone(tobits);
#endif
send1Frame(tobits,block->mChannelCoding,0);
#if FEC_DEBUG
BitVector *result = debugDecoder.getResult();
devassert(result);
devassert(copybits == tobits);
if (result && !(*result == tobits)) {
int diffbit = -1;
char thing[500];
for (int i = 0; i < (int)result->size(); i++) {
thing[i] = '-';
if (result->bit(i) != tobits.bit(i)) {
if (diffbit == -1) diffbit = i;
thing[i] = '0' + result->bit(i);
}
}
thing[result->size()] = 0;
GPRSLOG(1) <<"encoding error" <<LOGVAR2("cs",(int)debugDecoder.getCS())
<<LOGVAR(diffbit)
<<LOGVAR2("in:size",tobits.size()) <<LOGVAR2("out:size",result->size())
<<"\n"<<tobits
<<"\n"<<*result
<<"\n"<<thing;
} else {
//GPRSLOG(1) <<"encoding ok" <<LOGVAR2("cs",(int)debugDecoder.getCS());
}
#endif
return true;
}
void ViterbiTCH_AFS7_4::decode(const SoftVector &in, BitVector& target)
{
ViterbiTCH_AFS7_4 &decoder = *this;
const size_t sz = in.size() - 12;
const unsigned deferral = decoder.deferral();
const size_t ctsz = sz + deferral*decoder.iRate();
assert(sz == decoder.iRate()*target.size());
// Build a "history" array where each element contains the full history.
uint32_t history[ctsz];
{
BitVector bits = in.sliced();
uint32_t accum = 0;
for (size_t i=0; i<sz; i++) {
accum = (accum<<1) | bits.bit(i);
history[i] = accum;
}
// Repeat last bit at the end.
for (size_t i=sz; i<ctsz; i++) {
accum = (accum<<1) | (accum & 0x01);
history[i] = accum;
}
}
// Precompute metric tables.
float matchCostTable[ctsz];
float mismatchCostTable[ctsz];
{
const float *dp = in.begin();
for (size_t i=0; i<sz; i++) {
// pVal is the probability that a bit is correct.
// ipVal is the probability that a bit is incorrect.
float pVal = dp[i];
if (pVal>0.5F) pVal = 1.0F-pVal;
float ipVal = 1.0F-pVal;
// This is a cheap approximation to an ideal cost function.
if (pVal<0.01F) pVal = 0.01;
if (ipVal<0.01F) ipVal = 0.01;
matchCostTable[i] = 0.25F/ipVal;
mismatchCostTable[i] = 0.25F/pVal;
}
// pad end of table with unknowns
for (size_t i=sz; i<ctsz; i++) {
matchCostTable[i] = 0.5F;
mismatchCostTable[i] = 0.5F;
}
}
{
decoder.initializeStates();
// Each sample of history[] carries its history.
// So we only have to process every iRate-th sample.
const unsigned step = decoder.iRate();
// input pointer
const uint32_t *ip = history + step - 1;
// output pointers
char *op = target.begin();
const char *const opt = target.end();
// table pointers
const float* match = matchCostTable;
const float* mismatch = mismatchCostTable;
size_t oCount = 0;
while (op<opt) {
// Viterbi algorithm
assert(match-matchCostTable<(int)(sizeof(matchCostTable)/sizeof(matchCostTable[0])-1));
assert(mismatch-mismatchCostTable<(int)(sizeof(mismatchCostTable)/sizeof(mismatchCostTable[0])-1));
const ViterbiTCH_AFS7_4::vCand &minCost = decoder.step(*ip, match, mismatch);
ip += step;
match += step;
mismatch += step;
// output
if (oCount>=deferral) *op++ = (minCost.iState >> deferral)&0x01;
oCount++;
}
}
}
