| Index: third_party/WebKit/Source/platform/audio/IIRFilter.h
|
| diff --git a/third_party/WebKit/Source/platform/audio/IIRFilter.h b/third_party/WebKit/Source/platform/audio/IIRFilter.h
|
| index c0d7ecc69f0784e14c2c236be021d7b97ec7dcfe..deeeffaf876d15e1dfd0f0007844d6e81422aaf3 100644
|
| --- a/third_party/WebKit/Source/platform/audio/IIRFilter.h
|
| +++ b/third_party/WebKit/Source/platform/audio/IIRFilter.h
|
| @@ -13,8 +13,9 @@ namespace blink {
|
|
|
| class PLATFORM_EXPORT IIRFilter final {
|
| public:
|
| - // The maximum IIR filter order. This also limits the number of feedforward coefficients. The
|
| - // maximum number of coefficients is 20 according to the spec.
|
| + // The maximum IIR filter order. This also limits the number of feedforward
|
| + // coefficients. The maximum number of coefficients is 20 according to the
|
| + // spec.
|
| const static size_t kMaxOrder = 19;
|
| IIRFilter(const AudioDoubleArray* feedforwardCoef,
|
| const AudioDoubleArray* feedbackCoef);
|
| @@ -32,25 +33,27 @@ class PLATFORM_EXPORT IIRFilter final {
|
| private:
|
| // Filter memory
|
| //
|
| - // For simplicity, we assume |m_xBuffer| and |m_yBuffer| have the same length, and the length is
|
| - // a power of two. Since the number of coefficients has a fixed upper length, the size of
|
| - // xBuffer and yBuffer is fixed. |m_xBuffer| holds the old input values and |m_yBuffer| holds
|
| - // the old output values needed to compute the new output value.
|
| + // For simplicity, we assume |m_xBuffer| and |m_yBuffer| have the same length,
|
| + // and the length is a power of two. Since the number of coefficients has a
|
| + // fixed upper length, the size of xBuffer and yBuffer is fixed. |m_xBuffer|
|
| + // holds the old input values and |m_yBuffer| holds the old output values
|
| + // needed to compute the new output value.
|
| //
|
| - // m_yBuffer[m_bufferIndex] holds the most recent output value, say, y[n]. Then
|
| - // m_yBuffer[m_bufferIndex - k] is y[n - k]. Similarly for m_xBuffer.
|
| + // m_yBuffer[m_bufferIndex] holds the most recent output value, say, y[n].
|
| + // Then m_yBuffer[m_bufferIndex - k] is y[n - k]. Similarly for m_xBuffer.
|
| //
|
| // To minimize roundoff, these arrays are double's instead of floats.
|
| AudioDoubleArray m_xBuffer;
|
| AudioDoubleArray m_yBuffer;
|
|
|
| - // Index into the xBuffer and yBuffer arrays where the most current x and y values should be
|
| - // stored. xBuffer[bufferIndex] corresponds to x[n], the current x input value and
|
| - // yBuffer[bufferIndex] is where y[n], the current output value.
|
| + // Index into the xBuffer and yBuffer arrays where the most current x and y
|
| + // values should be stored. xBuffer[bufferIndex] corresponds to x[n], the
|
| + // current x input value and yBuffer[bufferIndex] is where y[n], the current
|
| + // output value.
|
| int m_bufferIndex;
|
|
|
| - // Coefficients of the IIR filter. To minimize storage, these point to the arrays given in the
|
| - // constructor.
|
| + // Coefficients of the IIR filter. To minimize storage, these point to the
|
| + // arrays given in the constructor.
|
| const AudioDoubleArray* m_feedback;
|
| const AudioDoubleArray* m_feedforward;
|
| };
|
|
|