1 /* 2 * Copyright (c) 2015 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 #ifndef WEBRTC_MODULES_AUDIO_PROCESSING_BEAMFORMER_ARRAY_UTIL_H_ 12 #define WEBRTC_MODULES_AUDIO_PROCESSING_BEAMFORMER_ARRAY_UTIL_H_ 13 14 #include <cmath> 15 #include <vector> 16 17 #include "webrtc/base/optional.h" 18 19 namespace webrtc { 20 21 // Coordinates in meters. The convention used is: 22 // x: the horizontal dimension, with positive to the right from the camera's 23 // perspective. 24 // y: the depth dimension, with positive forward from the camera's 25 // perspective. 26 // z: the vertical dimension, with positive upwards. 27 template<typename T> 28 struct CartesianPoint { 29 CartesianPoint() { 30 c[0] = 0; 31 c[1] = 0; 32 c[2] = 0; 33 } 34 CartesianPoint(T x, T y, T z) { 35 c[0] = x; 36 c[1] = y; 37 c[2] = z; 38 } 39 T x() const { return c[0]; } 40 T y() const { return c[1]; } 41 T z() const { return c[2]; } 42 T c[3]; 43 }; 44 45 using Point = CartesianPoint<float>; 46 47 // Calculates the direction from a to b. 48 Point PairDirection(const Point& a, const Point& b); 49 50 float DotProduct(const Point& a, const Point& b); 51 Point CrossProduct(const Point& a, const Point& b); 52 53 bool AreParallel(const Point& a, const Point& b); 54 bool ArePerpendicular(const Point& a, const Point& b); 55 56 // Returns the minimum distance between any two Points in the given 57 // |array_geometry|. 58 float GetMinimumSpacing(const std::vector<Point>& array_geometry); 59 60 // If the given array geometry is linear it returns the direction without 61 // normalizing. 62 rtc::Optional<Point> GetDirectionIfLinear( 63 const std::vector<Point>& array_geometry); 64 65 // If the given array geometry is planar it returns the normal without 66 // normalizing. 67 rtc::Optional<Point> GetNormalIfPlanar( 68 const std::vector<Point>& array_geometry); 69 70 // Returns the normal of an array if it has one and it is in the xy-plane. 71 rtc::Optional<Point> GetArrayNormalIfExists( 72 const std::vector<Point>& array_geometry); 73 74 // The resulting Point will be in the xy-plane. 75 Point AzimuthToPoint(float azimuth); 76 77 template<typename T> 78 float Distance(CartesianPoint<T> a, CartesianPoint<T> b) { 79 return std::sqrt((a.x() - b.x()) * (a.x() - b.x()) + 80 (a.y() - b.y()) * (a.y() - b.y()) + 81 (a.z() - b.z()) * (a.z() - b.z())); 82 } 83 84 // The convention used: 85 // azimuth: zero is to the right from the camera's perspective, with positive 86 // angles in radians counter-clockwise. 87 // elevation: zero is horizontal, with positive angles in radians upwards. 88 // radius: distance from the camera in meters. 89 template <typename T> 90 struct SphericalPoint { 91 SphericalPoint(T azimuth, T elevation, T radius) { 92 s[0] = azimuth; 93 s[1] = elevation; 94 s[2] = radius; 95 } 96 T azimuth() const { return s[0]; } 97 T elevation() const { return s[1]; } 98 T distance() const { return s[2]; } 99 T s[3]; 100 }; 101 102 using SphericalPointf = SphericalPoint<float>; 103 104 // Helper functions to transform degrees to radians and the inverse. 105 template <typename T> 106 T DegreesToRadians(T angle_degrees) { 107 return M_PI * angle_degrees / 180; 108 } 109 110 template <typename T> 111 T RadiansToDegrees(T angle_radians) { 112 return 180 * angle_radians / M_PI; 113 } 114 115 } // namespace webrtc 116 117 #endif // WEBRTC_MODULES_AUDIO_PROCESSING_BEAMFORMER_ARRAY_UTIL_H_ 118
