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interpolation & oversampling changes

pull/5/head
Oona 2013-01-20 02:17:38 +02:00
rodzic b8801a673a
commit 336c01849f
2 zmienionych plików z 24 dodań i 20 usunięć
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2
sync.c
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@ -108,7 +108,7 @@ double FindSync (guchar Mode, double Rate, int *Skip) {
for (int i=0;i<8;i++) convd += xAcc[x+i] * ConvoFilter[i];
if (convd > maxconvd) {
maxconvd = convd;
xmax = x;
xmax = x+4;
}
}

42
video.c
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@ -28,7 +28,7 @@ gboolean GetVideo(guchar Mode, double Rate, int Skip, gboolean Redraw) {
int LineNum = 0, SampleNum, Length;
int x = 0, y = 0, prevline=0, tx=0;
double Hann[7][1024] = {{0}};
double t=0, Freq = 0, PrevFreq = 0, InterpFreq = 0, NextPixelTime = 0, NextSNRtime = 0, NextFFTtime = 0;
double t=0, Freq = 0, PrevFreq = 0, InterpFreq = 0, NextPixelTime = 0, NextSNRtime = 0;
double NextSyncTime = 0;
double Praw, Psync;
double Power[1024] = {0};
@ -40,8 +40,8 @@ gboolean GetVideo(guchar Mode, double Rate, int Skip, gboolean Redraw) {
guchar Channel = 0, WinIdx = 0;
// Initialize Hann windows of different lengths
gushort HannLens[5] = { 96, 128, 256, 512, 1024 };
for (j = 0; j < 5; j++)
gushort HannLens[6] = { 64, 96, 128, 256, 512, 1024 };
for (j = 0; j < 6; j++)
for (i = 0; i < HannLens[j]; i++)
Hann[j][i] = 0.5 * (1 - cos( (2 * M_PI * i) / (HannLens[j] - 1)) );
@ -125,7 +125,7 @@ gboolean GetVideo(guchar Mode, double Rate, int Skip, gboolean Redraw) {
memset(out, 0, sizeof(out[0])*FFTLen);
// Hann window
for (i = 0; i < 96; i++) in[i] = pcm.Buffer[pcm.WindowPtr+i-48] / 32768.0 * Hann[0][i];
for (i = 0; i < 64; i++) in[i] = pcm.Buffer[pcm.WindowPtr+i-32] / 32768.0 * Hann[0][i];
fftw_execute(Plan1024);
@ -156,7 +156,7 @@ gboolean GetVideo(guchar Mode, double Rate, int Skip, gboolean Redraw) {
if (t >= NextSNRtime) {
// Apply Hann window
for (i = 0; i < FFTLen; i++) in[i] = pcm.Buffer[pcm.WindowPtr + i - FFTLen/2] / 32768.0 * Hann[4][i];
for (i = 0; i < FFTLen; i++) in[i] = pcm.Buffer[pcm.WindowPtr + i - FFTLen/2] / 32768.0 * Hann[5][i];
// FFT
fftw_execute(Plan1024);
@ -197,22 +197,23 @@ gboolean GetVideo(guchar Mode, double Rate, int Skip, gboolean Redraw) {
/*** FM demodulation ***/
if (t >= NextFFTtime) {
if (t >= NextPixelTime) {
PrevFreq = Freq;
// Adapt window size to SNR
if (!Adaptive) WinIdx = 0;
else if (SNR >= 9) WinIdx = 0;
else if (SNR >= 3) WinIdx = 1;
else if (SNR >= -5) WinIdx = 2;
else if (SNR >= -10) WinIdx = 3;
else WinIdx = 4;
else if (SNR >= 10) WinIdx = 0;
else if (SNR >= 9) WinIdx = 1;
else if (SNR >= 3) WinIdx = 2;
else if (SNR >= -5) WinIdx = 3;
else if (SNR >= -10) WinIdx = 4;
else WinIdx = 5;
// Minimum winlength can be doubled for Scottie DX
if (Mode == SDX && WinIdx < 4) WinIdx++;
if (Mode == SDX && WinIdx < 5) WinIdx++;
WinLength = HannLens[WinIdx];
@ -246,12 +247,10 @@ gboolean GetVideo(guchar Mode, double Rate, int Skip, gboolean Redraw) {
Freq = ( (MaxBin > GetBin(1900 + CurrentPic.HedrShift, FFTLen)) ? 2300 : 1500 ) + CurrentPic.HedrShift;
}
NextFFTtime += 0.3e-3;
}
// Linear interpolation of (chronologically) intermediate frequencies
InterpFreq = PrevFreq + (t - NextFFTtime + 0.6e-3) * ((Freq - PrevFreq) / 0.3e-3);
InterpFreq = PrevFreq + (Freq-PrevFreq) * ((t-(NextPixelTime-ModeSpec[Mode].PixelLen))/ModeSpec[Mode].PixelLen);
// Calculate luminency & store for later use
StoredLum[SampleNum] = clip((InterpFreq - (1500 + CurrentPic.HedrShift)) / 3.1372549);
@ -261,10 +260,10 @@ gboolean GetVideo(guchar Mode, double Rate, int Skip, gboolean Redraw) {
/*** Are we on a video line, and should we sample a pixel? ***/
if ( ( (CurLineTime >= ChanStart[0] && CurLineTime < ChanStart[0] + ChanLen[0])
if ( ((CurLineTime >= ChanStart[0] && CurLineTime < ChanStart[0] + ChanLen[0])
|| (CurLineTime >= ChanStart[1] && CurLineTime < ChanStart[1] + ChanLen[1])
|| (CurLineTime >= ChanStart[2] && CurLineTime < ChanStart[2] + ChanLen[2]) )
&& t >= NextPixelTime
&& t >= NextPixelTime
) {
LineNum = t / ModeSpec[Mode].LineLen;
@ -381,9 +380,14 @@ gboolean GetVideo(guchar Mode, double Rate, int Skip, gboolean Redraw) {
gdk_threads_leave();
}
}
if (LineNum > prevline)
NextPixelTime = t + ModeSpec[Mode].PixelLen/3; // take 3 samples per pixel; to better allow for redraw
else
NextPixelTime += ModeSpec[Mode].PixelLen/3;
prevline = LineNum;
NextPixelTime += ModeSpec[Mode].PixelLen / 2;
}
if (!Redraw && SampleNum % 8820 == 0) {