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For in_snsf, replaced the B-spline interpolation with the 6-point, 5th-order version, and replaced the Optimal interpolation with 6-point, 5th-order 2nd-order Osculating.

Naram Qashat authored on 2013/04/12 13:36:31
Showing 1 changed files
src/in_snsf/snes9x/apu/optimal_resampler.h
History View file @ f43812d
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-/* Simple resampler based on bsnes's ruby audio library */
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-
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-#ifndef __OPTIMAL_RESAMPLER_H
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-#define __OPTIMAL_RESAMPLER_H
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-
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-#include <cmath>
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-#include "resampler.h"
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-
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-#undef CLAMP
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-#undef SHORT_CLAMP
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-//template<typename T1, typename T2> static inline T1 CLAMP(T1 x, T2 low, T2 high) { return x > high ? high : (x < low ? low : x); }
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-//template<typename T> static inline short SHORT_CLAMP(T n) { return static_cast<short>(CLAMP(n, -32768, 32767)); }
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-
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-class OptimalResampler : public Resampler
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-{
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-protected:
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-	double r_step;
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-	double r_frac;
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-	int r_left[4], r_right[4];
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-
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-	double optimal(double x, double a, double b, double c, double d)
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-	{
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-		double z = x - 0.5;
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-		double even1 = c + b, odd1 = c - b;
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-		double even2 = d + a, odd2 = d - a;
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-		double c0 = even1 * 0.46822774170144532 + even2 * 0.03177225758005808;
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-		double c1 = odd1 * 0.55890365706150436 + odd2 * 0.14703258836343669;
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-		double c2 = even1 * -0.250153411893796031 + even2 * 0.25015343462990891;
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-		double c3 = odd1 * -0.49800710906733769 + odd2 * 0.16600005174304033;
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-		double c4 = even1 * 0.00064264050033187 + even2 * -0.00064273459469381;
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-		return (((c4 * z + c3) * z + c2) * z + c1) * z + c0;
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-	}
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-
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-public:
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-	OptimalResampler(int num_samples) : Resampler(num_samples)
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-	{
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-		this->clear();
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-	}
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-
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-	void time_ratio(double ratio)
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-	{
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-		this->r_step = ratio;
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-		this->clear();
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-	}
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-
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-	void clear()
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-	{
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-		ring_buffer::clear ();
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-		this->r_frac = 1.0;
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-		this->r_left[0] = this->r_left[1] = this->r_left[2] = this->r_left[3] = 0;
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-		this->r_right[0] = this->r_right[1] = this->r_right[2] = this->r_right[3] = 0;
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-	}
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-
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-	void read(short *data, int num_samples)
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-	{
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-		int i_position = this->start >> 1;
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-		short *internal_buffer = reinterpret_cast<short *>(this->buffer);
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-		int o_position = 0;
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-		int consumed = 0;
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-
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-		while (o_position < num_samples && consumed < this->buffer_size)
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-		{
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-			int s_left = internal_buffer[i_position];
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-			int s_right = internal_buffer[i_position + 1];
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-			int max_samples = this->buffer_size >> 1;
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-			const double margin_of_error = 1.0e-10;
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-
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-			if (std::abs(this->r_step - 1.0) < margin_of_error)
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-			{
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-				data[o_position] = static_cast<short>(s_left);
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-				data[o_position + 1] = static_cast<short>(s_right);
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-
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-				o_position += 2;
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-				i_position += 2;
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-				if (i_position >= max_samples)
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-					i_position -= max_samples;
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-				consumed += 2;
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-
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-				continue;
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-			}
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-
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-			while (this->r_frac <= 1.0 && o_position < num_samples)
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-			{
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-				data[o_position] = SHORT_CLAMP(optimal(this->r_frac, this->r_left[0], this->r_left[1], this->r_left[2], this->r_left[3]));
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-				data[o_position + 1] = SHORT_CLAMP(optimal(this->r_frac, this->r_right[0], this->r_right[1], this->r_right[2], this->r_right[3]));
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-
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-				o_position += 2;
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-
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-				this->r_frac += this->r_step;
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-			}
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-
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-			if (this->r_frac > 1.0)
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-			{
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-				this->r_left[0] = this->r_left[1];
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-				this->r_left[1] = this->r_left[2];
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-				this->r_left[2] = this->r_left[3];
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-				this->r_left[3] = s_left;
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-
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-				this->r_right[0] = this->r_right[1];
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-				this->r_right[1] = this->r_right[2];
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-				this->r_right[2] = this->r_right[3];
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-				this->r_right[3] = s_right;
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-
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-				this->r_frac -= 1.0;
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-
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-				i_position += 2;
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-				if (i_position >= max_samples)
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-					i_position -= max_samples;
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-				consumed += 2;
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-			}
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-		}
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-
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-		this->size -= consumed << 1;
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-		this->start += consumed << 1;
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-		if (this->start >= this->buffer_size)
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-			this->start -= this->buffer_size;
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-	}
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-
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-	inline int avail()
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-	{
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-		return static_cast<int>(std::floor(((this->size >> 2) - this->r_frac) / this->r_step) * 2);
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-	}
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-};
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-
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-#endif /* __OPTIMAL_RESAMPLER_H */
Browse code

Added B-spline and Optimal interpolations to in_snsf, but I'll probably be changing this later.

Naram Qashat authored on 2013/04/12 10:24:45
Showing 1 changed files
src/in_snsf/snes9x/apu/optimal_resampler.h
History View file @ 5b57f97
1 1 
new file mode 100644
... ... 
@@ -0,0 +1,125 @@
1 
+/* Simple resampler based on bsnes's ruby audio library */
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+
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+#ifndef __OPTIMAL_RESAMPLER_H
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+#define __OPTIMAL_RESAMPLER_H
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+
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+#include <cmath>
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+#include "resampler.h"
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+
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+#undef CLAMP
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+#undef SHORT_CLAMP
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+//template<typename T1, typename T2> static inline T1 CLAMP(T1 x, T2 low, T2 high) { return x > high ? high : (x < low ? low : x); }
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+//template<typename T> static inline short SHORT_CLAMP(T n) { return static_cast<short>(CLAMP(n, -32768, 32767)); }
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+
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+class OptimalResampler : public Resampler
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+{
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+protected:
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+	double r_step;
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+	double r_frac;
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+	int r_left[4], r_right[4];
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+
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+	double optimal(double x, double a, double b, double c, double d)
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+	{
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+		double z = x - 0.5;
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+		double even1 = c + b, odd1 = c - b;
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+		double even2 = d + a, odd2 = d - a;
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+		double c0 = even1 * 0.46822774170144532 + even2 * 0.03177225758005808;
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+		double c1 = odd1 * 0.55890365706150436 + odd2 * 0.14703258836343669;
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+		double c2 = even1 * -0.250153411893796031 + even2 * 0.25015343462990891;
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+		double c3 = odd1 * -0.49800710906733769 + odd2 * 0.16600005174304033;
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+		double c4 = even1 * 0.00064264050033187 + even2 * -0.00064273459469381;
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+		return (((c4 * z + c3) * z + c2) * z + c1) * z + c0;
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+	}
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+
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+public:
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+	OptimalResampler(int num_samples) : Resampler(num_samples)
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+	{
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+		this->clear();
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+	}
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+
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+	void time_ratio(double ratio)
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+	{
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+		this->r_step = ratio;
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+		this->clear();
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+	}
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+
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+	void clear()
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+	{
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+		ring_buffer::clear ();
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+		this->r_frac = 1.0;
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+		this->r_left[0] = this->r_left[1] = this->r_left[2] = this->r_left[3] = 0;
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+		this->r_right[0] = this->r_right[1] = this->r_right[2] = this->r_right[3] = 0;
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+	}
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+
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+	void read(short *data, int num_samples)
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+	{
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+		int i_position = this->start >> 1;
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+		short *internal_buffer = reinterpret_cast<short *>(this->buffer);
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+		int o_position = 0;
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+		int consumed = 0;
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+
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+		while (o_position < num_samples && consumed < this->buffer_size)
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+		{
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+			int s_left = internal_buffer[i_position];
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+			int s_right = internal_buffer[i_position + 1];
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+			int max_samples = this->buffer_size >> 1;
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+			const double margin_of_error = 1.0e-10;
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+
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+			if (std::abs(this->r_step - 1.0) < margin_of_error)
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+			{
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+				data[o_position] = static_cast<short>(s_left);
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+				data[o_position + 1] = static_cast<short>(s_right);
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+
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+				o_position += 2;
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+				i_position += 2;
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+				if (i_position >= max_samples)
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+					i_position -= max_samples;
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+				consumed += 2;
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+
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+				continue;
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+			}
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+
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+			while (this->r_frac <= 1.0 && o_position < num_samples)
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+			{
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+				data[o_position] = SHORT_CLAMP(optimal(this->r_frac, this->r_left[0], this->r_left[1], this->r_left[2], this->r_left[3]));
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+				data[o_position + 1] = SHORT_CLAMP(optimal(this->r_frac, this->r_right[0], this->r_right[1], this->r_right[2], this->r_right[3]));
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+
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+				o_position += 2;
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+
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+				this->r_frac += this->r_step;
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+			}
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+
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+			if (this->r_frac > 1.0)
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+			{
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+				this->r_left[0] = this->r_left[1];
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+				this->r_left[1] = this->r_left[2];
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+				this->r_left[2] = this->r_left[3];
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+				this->r_left[3] = s_left;
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+
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+				this->r_right[0] = this->r_right[1];
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+				this->r_right[1] = this->r_right[2];
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+				this->r_right[2] = this->r_right[3];
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+				this->r_right[3] = s_right;
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+
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+				this->r_frac -= 1.0;
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+
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+				i_position += 2;
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+				if (i_position >= max_samples)
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+					i_position -= max_samples;
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+				consumed += 2;
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+			}
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+		}
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+
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+		this->size -= consumed << 1;
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+		this->start += consumed << 1;
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+		if (this->start >= this->buffer_size)
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+			this->start -= this->buffer_size;
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+	}
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+
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+	inline int avail()
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+	{
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+		return static_cast<int>(std::floor(((this->size >> 2) - this->r_frac) / this->r_step) * 2);
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+	}
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+};
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+
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+#endif /* __OPTIMAL_RESAMPLER_H */