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+/*
+ * Copyright (C) 2011, Google Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+
+#if ENABLE(WEB_AUDIO)
+
+#include "WaveShaperDSPKernel.h"
+
+#include "WaveShaperProcessor.h"
+#include <algorithm>
+
+using namespace std;
+
+namespace WebCore {
+
+void WaveShaperDSPKernel::process(const float* source, float* destination, size_t framesToProcess)
+{
+ ASSERT(source && destination && waveShaperProcessor());
+
+ Float32Array* curve = waveShaperProcessor()->curve();
+ if (!curve) {
+ // Act as "straight wire" pass-through if no curve is set.
+ memcpy(destination, source, sizeof(float) * framesToProcess);
+ return;
+ }
+
+ float* curveData = curve->data();
+ int curveLength = curve->length();
+
+ ASSERT(curveData);
+
+ if (!curveData || !curveLength) {
+ memcpy(destination, source, sizeof(float) * framesToProcess);
+ return;
+ }
+
+ // Apply waveshaping curve.
+ for (unsigned i = 0; i < framesToProcess; ++i) {
+ const float input = source[i];
+
+ // Calculate an index based on input -1 -> +1 with 0 being at the center of the curve data.
+ int index = (curveLength * (input + 1)) / 2;
+
+ // Clip index to the input range of the curve.
+ // This takes care of input outside of nominal range -1 -> +1
+ index = max(index, 0);
+ index = min(index, curveLength - 1);
+ destination[i] = curveData[index];
+ }
+}
+
+} // namespace WebCore
+
+#endif // ENABLE(WEB_AUDIO)