1 files changed, 22 insertions, 0 deletions
diff --git a/examples/7_iir_echo.cpp b/examples/7_iir_echo.cpp
new file mode 100644
index 0000000..57e5605
--- /dev/null
+++ b/examples/7_iir_echo.cpp
@@ -0,0 +1,22 @@
+Sample *process_data(Samples samples)
+{
+	constexpr float alpha = 0.75;
+	constexpr unsigned int D = 100;
+
+	static Sample output[samples.size()];
+	static Sample prev[D]; // prev[0] = output[0 - D]
+
+	// Do calculations with previous output
+	for (unsigned int i = 0; i < D; i++)
+		output[i] = samples[i] + alpha * (prev[i] - 2048);
+
+	// Do calculations with current samples
+	for (unsigned int i = D; i < samples.size(); i++)
+		output[i] = samples[i] + alpha * (output[i - D] - 2048);
+
+	// Save outputs for next computation
+	for (unsigned int i = 0; i < D; i++)
+		prev[i] = output[samples.size() - (D - i)];
+
+	return output;
+}