comparison carfac/carfac_common.h @ 609:aefe2ca0674f

First version of a C++ implementation by Alex Brandmeyer

+//
+//  carfac_common.h
+//  CARFAC Open Source C++ Library
+//
+//  Created by Alex Brandmeyer on 5/10/13.
+//
+// This C++ file is part of an implementation of Lyon's cochlear model:
+// "Cascade of Asymmetric Resonators with Fast-Acting Compression"
+// to supplement Lyon's upcoming book "Human and Machine Hearing"
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// *****************************************************************************
+// carfac_common.h
+// *****************************************************************************
+// This file contains the base level definitions and includes used within the
+// CARFAC C++ library. It also defines some low level functions which are used
+// during the calculation of the various coefficient sets required by the model.
+//
+// The current implementation of the library is dependent on the use of the
+// Eigen C++ library for linear algebra. Specifically, Eigen Arrays are used
+// extensively for coefficient wise operations during both the design and run
+// stages of the model.
+//
+// The 'FPType' typedef is specified in this file in order to enable quick
+// switching between precision levels (i.e. float vs. double) throughout the
+// library. The remainder of the code uses this type for specifying floating
+// point scalars.
+//
+// Two additional typedefs are defined for one and two dimensional arrays:
+// FloatArray and FloatArray2d. These in turn make use of FPType so that the
+// precision level across floating point data is consistent.
+//
+// The functions 'ERBHz' and 'CARFACDetect' are defined here, and are used
+// during the design stage of a CARFAC model. 
+
+#ifndef CARFAC_Open_Source_C__Library_CARFACCommon_h
+#define CARFAC_Open_Source_C__Library_CARFACCommon_h
+
+#include <iostream> //Used for debugging output, could go in final version
+#include <math.h> //Used during coefficient calculations
+#include <Eigen/Dense> //Used for 1d and 2d floating point arrays
+using namespace Eigen;
+
+#define PI 3.141592
+typedef float FPType; //Used to enable easy switching in precision level
+
+//typedefs for Eigen floating point arrays
+typedef Eigen::Array<FPType,Dynamic,1> FloatArray; //1d floating point array
+typedef Eigen::Array<FPType,Dynamic,Dynamic> FloatArray2d; //2d fpoint array
+
+// Function: ERBHz
+// Auditory filter nominal Equivalent Rectangular Bandwidth
+// Ref: Glasberg and Moore: Hearing Research, 47 (1990), 103-138
+FPType ERBHz(FPType cf_hz, FPType erb_break_freq, FPType erb_q);
+
+// Function CARFACDetect
+// TODO explain a bit more
+FPType CARFACDetect (FPType x);
+FloatArray CARFACDetect (FloatArray x);
+#endif