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the AutoCorrelate...

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This commit is contained in:
iceman1001 2017-07-27 21:36:49 +02:00
parent 4431e418f8
commit f1544dc4bf
2 changed files with 8 additions and 9 deletions
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15
client/cmddata.c
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@ -860,17 +860,17 @@ int Cmdaskrawdemod(const char *Cmd)
return ASKDemod(Cmd, true, false, 0);
}
int AutoCorrelate(int window, bool SaveGrph, bool verbose)
int AutoCorrelate(const int *in, int *out, size_t len, int window, bool SaveGrph, bool verbose)
{
static int CorrelBuffer[MAX_GRAPH_TRACE_LEN];
size_t Correlation = 0;
int maxSum = 0;
int lastMax = 0;
if (verbose) PrintAndLog("performing %d correlations", GraphTraceLen - window);
for (int i = 0; i < GraphTraceLen - window; ++i) {
for (int i = 0; i < len - window; ++i) {
int sum = 0;
for (int j = 0; j < window; ++j) {
sum += (GraphBuffer[j]*GraphBuffer[i + j]) / 256;
sum += (in[j]*in[i + j]) / 256;
}
CorrelBuffer[i] = sum;
if (sum >= maxSum-100 && sum <= maxSum+100){
@ -885,20 +885,19 @@ int AutoCorrelate(int window, bool SaveGrph, bool verbose)
}
if (Correlation==0){
//try again with wider margin
for (int i = 0; i < GraphTraceLen - window; i++){
for (int i = 0; i < len - window; i++) {
if (CorrelBuffer[i] >= maxSum-(maxSum*0.05) && CorrelBuffer[i] <= maxSum+(maxSum*0.05)){
//another max
Correlation = i-lastMax;
lastMax = i;
//if (CorrelBuffer[i] > maxSum) maxSum = sum;
}
}
}
if (verbose && Correlation > 0) PrintAndLog("Possible Correlation: %d samples",Correlation);
if (SaveGrph){
GraphTraceLen = GraphTraceLen - window;
memcpy(GraphBuffer, CorrelBuffer, GraphTraceLen * sizeof (int));
//GraphTraceLen = GraphTraceLen - window;
memcpy(out, CorrelBuffer, len * sizeof(int));
RepaintGraphWindow();
}
return Correlation;
@ -918,7 +917,7 @@ int CmdAutoCorr(const char *Cmd)
return 0;
}
if (grph == 'g') updateGrph = true;
return AutoCorrelate(window, updateGrph, true);
return AutoCorrelate(GraphBuffer, GraphBuffer, GraphTraceLen, window, updateGrph, true);
}
int CmdBitsamples(const char *Cmd)

2
client/cmddata.h
View file

@ -29,7 +29,7 @@ int CmdVikingDemod(const char *Cmd);
int CmdG_Prox_II_Demod(const char *Cmd);
int Cmdaskrawdemod(const char *Cmd);
int Cmdaskmandemod(const char *Cmd);
int AutoCorrelate(int window, bool SaveGrph, bool verbose);
int AutoCorrelate(const int *in, int *out, size_t len, int window, bool SaveGrph, bool verbose);
int CmdAskEdgeDetect(const char *Cmd);
int CmdAutoCorr(const char *Cmd);
int CmdBiphaseDecodeRaw(const char *Cmd);