1 files changed, 33 insertions, 0 deletions
diff --git a/test/analysis/AnalysisDistortion.c b/test/analysis/AnalysisDistortion.c
new file mode 100644
index 0000000..27b8492
--- /dev/null
+++ b/test/analysis/AnalysisDistortion.c
@@ -0,0 +1,33 @@
+#include <stdlib.h>
+#include "AnalysisDistortion.h"
+
+// If two samples differ by more than this amount, then we call it distortion
+static const Sample kAnalysisDistortionTolerance = 0.5f;
+
+boolByte analysisDistortion(const SampleBuffer sampleBuffer, AnalysisFunctionData data)
+{
+    Sample difference;
+
+    for (ChannelCount channelIndex = 0; channelIndex < sampleBuffer->numChannels; channelIndex++) {
+        for (SampleCount sampleIndex = 0; sampleIndex < sampleBuffer->blocksize; sampleIndex++) {
+            if (sampleBuffer->samples[channelIndex][sampleIndex] > data->lastSample[channelIndex]) {
+                difference = sampleBuffer->samples[channelIndex][sampleIndex] - data->lastSample[channelIndex];
+            } else {
+                difference = data->lastSample[channelIndex] - sampleBuffer->samples[channelIndex][sampleIndex];
+            }
+
+            if (difference >= kAnalysisDistortionTolerance) {
+                // In this test, we don't care about the consecutive sample count. That is because
+                // we also want to detect harsh clicks which occur by a jump in the amplitude, which
+                // is a common error in many plugins.
+                data->failedChannel = channelIndex;
+                data->failedSample = sampleIndex;
+                return false;
+            }
+
+            data->lastSample[channelIndex] = sampleBuffer->samples[channelIndex][sampleIndex];
+        }
+    }
+
+    return true;
+}