@@ -43,7 +43,6 @@ TempSndReg::TempSndReg() : CR(0), SOURCE(nullptr), TIMER(0), REPEAT_POINT(0), LE

 }

 bool Channel::initializedLUTs = false;

-double Channel::cosine_lut[Channel::COSINE_RESOLUTION];

 double Channel::sinc_lut[Channel::SINC_SAMPLES + 1];

 #ifndef M_PI

@@ -62,8 +61,6 @@ Channel::Channel() : chnId(-1), tempReg(), state(CS_NONE), trackId(-1), prio(0),

 {

 	if (!this->initializedLUTs)

 	{

-		for (unsigned i = 0; i < COSINE_RESOLUTION; ++i)

-			this->cosine_lut[i] = (1.0 - std::cos((static_cast<double>(i) / COSINE_RESOLUTION) * M_PI)) * 0.5;

 		double dx = static_cast<double>(SINC_WIDTH) / SINC_SAMPLES, x = 0.0;

 		for (unsigned i = 0; i <= SINC_SAMPLES; ++i, x += dx)

 			this->sinc_lut[i] = std::abs(x) < SINC_WIDTH ? sinc(x) * sinc(x / SINC_WIDTH) : 0.0;

@@ -621,52 +618,33 @@ int32_t Channel::Interpolate()

 			sum += data[i - static_cast<int>(SINC_WIDTH) + 1] * kernel[i];

 		return static_cast<int32_t>(sum / kernel_sum);

 	}

-	else if (this->ply->interpolation > INTERPOLATION_COSINE)

+	else if (this->ply->interpolation > INTERPOLATION_LINEAR)

 	{

 		double c0, c1, c2, c3, c4, c5;

-		if (this->ply->interpolation > INTERPOLATION_4POINTBSPLINE)

+		if (this->ply->interpolation == INTERPOLATION_6POINTLEGRANGE)

 		{

-			if (this->ply->interpolation == INTERPOLATION_6POINTBSPLINE)

-			{

-				double ym2py2 = data[-2] + data[2], ym1py1 = data[-1] + data[1];

-				double y2mym2 = data[2] - data[-2], y1mym1 = data[1] - data[-1];

-				double sixthym1py1 = 1 / 6.0 * ym1py1;

-				c0 = 1 / 120.0 * ym2py2 + 13 / 60.0 * ym1py1 + 0.55 * data[0];

-				c1 = 1 / 24.0 * y2mym2 + 5 / 12.0 * y1mym1;

-				c2 = 1 / 12.0 * ym2py2 + sixthym1py1 - 0.5 * data[0];

-				c3 = 1 / 12.0 * y2mym2 - 1 / 6.0 * y1mym1;

-				c4 = 1 / 24.0 * ym2py2 - sixthym1py1 + 0.25 * data[0];

-				c5 = 1 / 120.0 * (data[3] - data[-2]) + 1 / 24.0 * (data[-1] - data[2]) + 1 / 12.0 * (data[1] - data[0]);

-				return static_cast<int32_t>(((((c5 * ratio + c4) * ratio + c3) * ratio + c2) * ratio + c1) * ratio + c0);

-			}

-			else // INTERPOLATION_6POINTOSCULATING

-			{

-				ratio -= 0.5;

-				double even1 = data[-2] + data[3], odd1 = data[-2] - data[3];

-				double even2 = data[-1] + data[2], odd2 = data[-1] - data[2];

-				double even3 = data[0] + data[1], odd3 = data[0] - data[1];

-				c0 = 0.01171875 * even1 - 0.09765625 * even2 + 0.5859375 * even3;

-				c1 = 0.2109375 * odd2 - 281 / 192.0 * odd3 - 13 / 384.0 * odd1;

-				c2 = 0.40625 * even2 - 17 / 48.0 * even3 - 5 / 96.0 * even1;

-				c3 = 0.1875 * odd1 - 53 / 48.0 * odd2 + 2.375 * odd3;

-				c4 = 1 / 48.0 * even1 - 0.0625 * even2 + 1 / 24.0 * even3;

-				c5 = 25 / 24.0 * odd2 - 25 / 12.0 * odd3 - 5 / 24.0 * odd1;

-				return static_cast<int32_t>(((((c5 * ratio + c4) * ratio + c3) * ratio + c2) * ratio + c1) * ratio + c0);

-			}

+			ratio -= 0.5;

+			double even1 = data[-2] + data[3], odd1 = data[-2] - data[3];

+			double even2 = data[-1] + data[2], odd2 = data[-1] - data[2];

+			double even3 = data[0] + data[1], odd3 = data[0] - data[1];

+			c0 = 0.01171875 * even1 - 0.09765625 * even2 + 0.5859375 * even3;

+			c1 = 25 / 384.0 * odd2 - 1.171875 * odd3 - 0.0046875 * odd1;

+			c2 = 0.40625 * even2 - 17 / 48.0 * even3 - 5 / 96.0 * even1;

+			c3 = 1 / 48.0 * odd1 - 13 / 48.0 * odd2 + 17 / 24.0 * odd3;

+			c4 = 1 / 48.0 * even1 - 0.0625 * even2 + 1 / 24.0 * even3;

+			c5 = 1 / 24.0 * odd2 - 1 / 12.0 * odd3 - 1 / 120.0 * odd1;

+			return static_cast<int32_t>(((((c5 * ratio + c4) * ratio + c3) * ratio + c2) * ratio + c1) * ratio + c0);

 		}

-		else // INTERPOLATION_4POINTBSPLINE

+		else // INTERPOLATION_4POINTLEAGRANGE

 		{

-			double ym1py1 = data[-1] + data[1];

-			c0 = 1 / 6.0 * ym1py1 + 2 / 3.0 * data[0];

-			c1 = 0.5 * (data[1] - data[-1]);

-			c2 = 0.5 * ym1py1 - data[0];

-			c3 = 0.5 * (data[0] - data[1]) + 1 / 6.0 * (data[2] - data[-1]);

+			c0 = data[0];

+			c1 = data[1] - 1 / 3.0 * data[-1] - 0.5 * data[0] - 1 / 6.0 * data[2];

+			c2 = 0.5 * (data[-1] + data[1]) - data[0];

+			c3 = 1 / 6.0 * (data[2] - data[-1]) + 0.5 * (data[0] - data[1]);

 			return static_cast<int32_t>(((c3 * ratio + c2) * ratio + c1) * ratio + c0);

 		}

 	}

-	else if (this->ply->interpolation == INTERPOLATION_COSINE)

-		return static_cast<int32_t>(data[0] + this->cosine_lut[static_cast<unsigned>(ratio * COSINE_RESOLUTION)] * (data[1] - data[0]));

 	else // INTERPOLATION_LINEAR

 		return static_cast<int32_t>(data[0] + ratio * (data[1] - data[0]));

 }

@@ -216,11 +216,9 @@ struct Channel

 	 * of the program.

 	 */

 	static bool initializedLUTs;

-	static const unsigned COSINE_RESOLUTION = 8192;

 	static const unsigned SINC_RESOLUTION = 8192;

 	static const unsigned SINC_WIDTH = 8;

 	static const unsigned SINC_SAMPLES = SINC_RESOLUTION * SINC_WIDTH;

-	static double cosine_lut[COSINE_RESOLUTION];

 	static double sinc_lut[SINC_SAMPLES + 1];

 	RingBuffer<SINC_WIDTH * 2> ringBuffer;

@@ -54,9 +54,7 @@ enum Interpolation

 {

 	INTERPOLATION_NONE,

 	INTERPOLATION_LINEAR,

-	INTERPOLATION_COSINE,

-	INTERPOLATION_4POINTBSPLINE,

-	INTERPOLATION_6POINTOSCULATING,

-	INTERPOLATION_6POINTBSPLINE,

+	INTERPOLATION_4POINTLEGRANGE,

+	INTERPOLATION_6POINTLEGRANGE,

 	INTERPOLATION_SINC

 };

@@ -42,7 +42,7 @@ public:

 unsigned XSFConfig::initSampleRate = 44100;

 std::string XSFConfig::commonName = "NCSF Decoder";

 std::string XSFConfig::versionNumber = "1.8.1";

-unsigned XSFConfig_NCSF::initInterpolation = 5;

+unsigned XSFConfig_NCSF::initInterpolation = 4;

 std::string XSFConfig_NCSF::initMutes = "0000000000000000";

 XSFConfig *XSFConfig::Create()

@@ -96,11 +96,9 @@ INT_PTR CALLBACK XSFConfig_NCSF::ConfigDialogProc(HWND hwndDlg, UINT uMsg, WPARA

 			// Interpolation

 			SendMessageW(GetDlgItem(hwndDlg, idInterpolation), CB_ADDSTRING, 0, reinterpret_cast<LPARAM>(L"None"));

 			SendMessageW(GetDlgItem(hwndDlg, idInterpolation), CB_ADDSTRING, 0, reinterpret_cast<LPARAM>(L"Linear"));

-			SendMessageW(GetDlgItem(hwndDlg, idInterpolation), CB_ADDSTRING, 0, reinterpret_cast<LPARAM>(L"Cosine"));

-			SendMessageW(GetDlgItem(hwndDlg, idInterpolation), CB_ADDSTRING, 0, reinterpret_cast<LPARAM>(L"4-point, 3rd-order B-spline"));

-			SendMessageW(GetDlgItem(hwndDlg, idInterpolation), CB_ADDSTRING, 0, reinterpret_cast<LPARAM>(L"6-point, 5th-order Osculating"));

-			SendMessageW(GetDlgItem(hwndDlg, idInterpolation), CB_ADDSTRING, 0, reinterpret_cast<LPARAM>(L"6-point, 5th-order B-spline"));

-			SendMessageW(GetDlgItem(hwndDlg, idInterpolation), CB_ADDSTRING, 0, reinterpret_cast<LPARAM>(L"Sinc (Lanczos Window)"));

+			SendMessageW(GetDlgItem(hwndDlg, idInterpolation), CB_ADDSTRING, 0, reinterpret_cast<LPARAM>(L"4-point, 3rd-order Legrange"));

+			SendMessageW(GetDlgItem(hwndDlg, idInterpolation), CB_ADDSTRING, 0, reinterpret_cast<LPARAM>(L"6-point, 5th-order Legrange"));

+			SendMessageW(GetDlgItem(hwndDlg, idInterpolation), CB_ADDSTRING, 0, reinterpret_cast<LPARAM>(L"16-point Sinc (Lanczos Window)"));

 			SendMessageW(GetDlgItem(hwndDlg, idInterpolation), CB_SETCURSEL, this->interpolation, 0);

 			// Mutes

 			for (int x = 0, numMutes = this->mutes.size(); x < numMutes; ++x)