1 files changed, 119 insertions, 0 deletions
diff --git a/chromium/third_party/webrtc/common_audio/fir_filter.cc b/chromium/third_party/webrtc/common_audio/fir_filter.cc
new file mode 100644
index 00000000000..a5411b888b4
--- /dev/null
+++ b/chromium/third_party/webrtc/common_audio/fir_filter.cc
@@ -0,0 +1,119 @@
+/*
+ *  Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/common_audio/fir_filter.h"
+
+#include <assert.h>
+#include <string.h>
+
+#include "webrtc/common_audio/fir_filter_neon.h"
+#include "webrtc/common_audio/fir_filter_sse.h"
+#include "webrtc/system_wrappers/interface/cpu_features_wrapper.h"
+#include "webrtc/system_wrappers/interface/scoped_ptr.h"
+
+namespace webrtc {
+
+class FIRFilterC : public FIRFilter {
+ public:
+  FIRFilterC(const float* coefficients,
+             size_t coefficients_length);
+
+  virtual void Filter(const float* in, size_t length, float* out) OVERRIDE;
+
+ private:
+  size_t coefficients_length_;
+  size_t state_length_;
+  scoped_ptr<float[]> coefficients_;
+  scoped_ptr<float[]> state_;
+};
+
+FIRFilter* FIRFilter::Create(const float* coefficients,
+                             size_t coefficients_length,
+                             size_t max_input_length) {
+  if (!coefficients || coefficients_length <= 0 || max_input_length <= 0) {
+    assert(false);
+    return NULL;
+  }
+
+  FIRFilter* filter = NULL;
+// If we know the minimum architecture at compile time, avoid CPU detection.
+#if defined(WEBRTC_ARCH_X86_FAMILY)
+#if defined(__SSE2__)
+  filter =
+      new FIRFilterSSE2(coefficients, coefficients_length, max_input_length);
+#else
+  // x86 CPU detection required.
+  if (WebRtc_GetCPUInfo(kSSE2)) {
+    filter =
+        new FIRFilterSSE2(coefficients, coefficients_length, max_input_length);
+  } else {
+    filter = new FIRFilterC(coefficients, coefficients_length);
+  }
+#endif
+#elif defined(WEBRTC_ARCH_ARM_V7)
+#if defined(WEBRTC_ARCH_ARM_NEON)
+  filter =
+      new FIRFilterNEON(coefficients, coefficients_length, max_input_length);
+#else
+  // ARM CPU detection required.
+  if (WebRtc_GetCPUFeaturesARM() & kCPUFeatureNEON) {
+    filter =
+        new FIRFilterNEON(coefficients, coefficients_length, max_input_length);
+  } else {
+    filter = new FIRFilterC(coefficients, coefficients_length);
+  }
+#endif
+#else
+  filter = new FIRFilterC(coefficients, coefficients_length);
+#endif
+
+  return filter;
+}
+
+FIRFilterC::FIRFilterC(const float* coefficients, size_t coefficients_length)
+    : coefficients_length_(coefficients_length),
+      state_length_(coefficients_length - 1),
+      coefficients_(new float[coefficients_length_]),
+      state_(new float[state_length_]) {
+  for (size_t i = 0; i < coefficients_length_; ++i) {
+    coefficients_[i] = coefficients[coefficients_length_ - i - 1];
+  }
+  memset(state_.get(), 0.f, state_length_ * sizeof(state_[0]));
+}
+
+void FIRFilterC::Filter(const float* in, size_t length, float* out) {
+  assert(length > 0);
+
+  // Convolves the input signal |in| with the filter kernel |coefficients_|
+  // taking into account the previous state.
+  for (size_t i = 0; i < length; ++i) {
+    out[i] = 0.f;
+    size_t j;
+    for (j = 0; state_length_ > i && j < state_length_ - i; ++j) {
+      out[i] += state_[i + j] * coefficients_[j];
+    }
+    for (; j < coefficients_length_; ++j) {
+      out[i] += in[j + i - state_length_] * coefficients_[j];
+    }
+  }
+
+  // Update current state.
+  if (length >= state_length_) {
+    memcpy(
+        state_.get(), &in[length - state_length_], state_length_ * sizeof(*in));
+  } else {
+    memmove(state_.get(),
+            &state_[length],
+            (state_length_ - length) * sizeof(state_[0]));
+    memcpy(&state_[state_length_ - length], in, length * sizeof(*in));
+  }
+}
+
+}  // namespace webrtc