| Preface |
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xiii | |
| Style |
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xiii | |
| Target audience |
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xiii | |
| Overview of structure |
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xiv | |
| Ingratitude |
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xiv | |
| Key points (tldr) |
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xvii | |
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1 Basic Notions and the Nature of the Fourier Transform |
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1 | (24) |
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1 | (2) |
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1.2 Software and reproducibility |
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3 | (2) |
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5 | (1) |
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6 | (3) |
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1.5 Analysing signals by their components: approximating functions by mathematical series |
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9 | (6) |
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9 | (3) |
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12 | (3) |
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1.6 What is the Fourier transform, and what can it do? |
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15 | (2) |
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1.7 Everyday use of the Fourier transform |
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17 | (4) |
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1.7.1 Transforms and speech recognition |
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18 | (1) |
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1.7.2 Transforms and image compression |
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18 | (1) |
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1.7.3 Human hearing and a transform |
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19 | (2) |
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1.7.4 Light and frequency |
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21 | (1) |
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1.8 Summary and further reading |
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21 | (4) |
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2 The Continuous Fourier Transform |
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25 | (50) |
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2.1 Continuous Fourier transform basis |
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25 | (13) |
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2.1.1 Continuous signals and their Fourier transform |
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25 | (4) |
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2.1.2 Magnitude and phase |
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29 | (1) |
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2.1.3 Inverse Fourier transform |
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30 | (3) |
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2.1.4 Fourier transform in Matlab |
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33 | (1) |
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2.1.5 Fourier transform pairs |
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34 | (1) |
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34 | (1) |
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35 | (1) |
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2.1.5.3 Gaussian function |
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35 | (3) |
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2.2 Properties of the continuous FT |
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38 | (9) |
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38 | (1) |
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39 | (1) |
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40 | (1) |
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2.2.4 Parseval's theorem (Rayleigh's theorem) |
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41 | (1) |
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42 | (1) |
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43 | (1) |
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2.2.7 Uncertainty principle |
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43 | (1) |
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44 | (3) |
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2.3 Processing signals using the FT |
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47 | (7) |
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47 | (4) |
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51 | (3) |
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2.4 What is the importance of phase? |
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54 | (2) |
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2.4.1 Phase in signal reconstruction |
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54 | (1) |
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2.4.2 Phase in shift invariance |
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55 | (1) |
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2.5 Windowing the FT data |
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56 | (9) |
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56 | (3) |
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2.5.2 Hanning and Hamming window operators |
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59 | (3) |
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62 | (2) |
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2.5.4 Other windowing functions |
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64 | (1) |
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2.6 Filtering the FT data |
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65 | (8) |
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2.6.1 Basic filters and signal processing |
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65 | (1) |
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2.6.1.1 Low-pass, high-pass and band-pass filters |
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65 | (2) |
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2.6.1.2 RC networks and transfer functions: low-pass filters |
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67 | (3) |
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2.6.1.3 CR networks and theory: high-pass filters |
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70 | (2) |
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72 | (1) |
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73 | (2) |
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3 The Discrete Fourier Transform |
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75 | (64) |
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75 | (7) |
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75 | (3) |
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3.1.2 Sampling process in the frequency domain |
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78 | (4) |
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3.2 The discrete Fourier transform |
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82 | (13) |
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82 | (3) |
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85 | (2) |
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3.2.3 Visualising the DFT data |
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87 | (4) |
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91 | (2) |
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93 | (1) |
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93 | (2) |
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95 | (1) |
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3.3 Properties of the DFT |
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95 | (8) |
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3.3.1 Basic considerations |
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96 | (1) |
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3.3.2 Linearity/Superposition |
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96 | (1) |
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96 | (1) |
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97 | (1) |
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3.3.5 Parseval's theorem (Rayleigh's theorem) |
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97 | (1) |
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98 | (1) |
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98 | (1) |
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3.3.8 Importance of phase - DFT |
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99 | (2) |
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3.3.9 Discrete data windowing functions |
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101 | (2) |
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3.4 Discrete convolution and correlation |
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103 | (8) |
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3.4.1 Discrete convolution |
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103 | (6) |
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3.4.2 Discrete correlation |
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109 | (2) |
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3.5 Digital filters; averaging and differencing samples |
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111 | (4) |
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3.6 The fast Fourier transform |
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115 | (21) |
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3.6.1 The butterfly operation and basic components of theFFT |
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115 | (1) |
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115 | (4) |
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3.6.1.2 FFT computation and speed |
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119 | (2) |
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3.6.1.3 Extending the FFT |
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121 | (3) |
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124 | (4) |
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128 | (2) |
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3.6.4 Computational time for FFT compared with DFT |
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130 | (1) |
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3.6.4.1 Improvement in speed vs DFT |
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130 | (2) |
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3.6.4.2 Speeding convolution via the convolution theorem |
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132 | (2) |
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134 | (1) |
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3.6.6 Even faster FFT algorithms |
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135 | (1) |
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136 | (3) |
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4 The Two-Dimensional Fourier Transform |
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139 | (40) |
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4.1 2-D functions and images |
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139 | (10) |
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139 | (1) |
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140 | (2) |
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142 | (3) |
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145 | (4) |
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4.1.5 Discrete image frequency components |
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149 | (1) |
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4.2 2-D Fourier transform and its inverse |
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149 | (6) |
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4.2.1 2-D continuous Fourier transform and separability |
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149 | (2) |
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4.2.2 2-D discrete Fourier transform |
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151 | (4) |
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4.3 Properties of the 2-D discrete Fourier transform |
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155 | (8) |
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155 | (1) |
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4.3.1.1 Transforms and their repetition |
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155 | (1) |
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4.3.1.2 Intensity normalisation |
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156 | (1) |
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157 | (2) |
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159 | (1) |
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160 | (1) |
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4.3.5 The importance of phase |
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161 | (1) |
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4.3.6 Computational cost of 2-D DFT and FFT |
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162 | (1) |
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4.4 Image processing via the Fourier transform |
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163 | (15) |
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163 | (1) |
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4.4.1.1 Image convolution |
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163 | (1) |
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4.4.1.2 Template convolution |
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164 | (2) |
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4.4.1.3 Filtering an image via convolution |
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166 | (2) |
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4.4.2 Computational considerations of image convolution and template convolution |
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168 | (2) |
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170 | (1) |
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4.4.3.1 Image correlation |
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170 | (1) |
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4.4.3.2 Template correlation/template matching |
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171 | (1) |
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4.4.3.3 Finding objects by template correlation/matching |
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172 | (3) |
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175 | (1) |
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4.4.4.1 Low-and high-pass filtering |
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175 | (2) |
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177 | (1) |
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178 | (1) |
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5 Variants of the Fourier Transform |
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179 | (38) |
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5.1 Cosine and sine transforms, including the discrete cosine transform |
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180 | (12) |
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5.1.1 1-D continuous transforms |
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180 | (1) |
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5.1.2 1-D discrete cosine and sine transforms |
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180 | (1) |
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5.1.2.1 Discrete cosine transform and compression |
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180 | (3) |
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183 | (3) |
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5.1.2.3 Relationship between the DCT and the DFT |
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186 | (3) |
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5.1.2.4 Other properties of the DCT |
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189 | (1) |
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5.1.2.5 Discrete sine transform |
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189 | (1) |
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5.1.3 2-D discrete cosine transform |
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190 | (2) |
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5.2 Walsh--Hadamard transform |
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192 | (5) |
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192 | (1) |
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5.2.1.1 The 1-D transform |
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192 | (3) |
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5.2.1.2 The 2-D Walsh transform |
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195 | (1) |
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5.2.2 Walsh--Hadamard transform |
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196 | (1) |
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197 | (3) |
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5.4 Image compression properties of Fourier, DCT, Walsh and Hartley transforms |
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200 | (3) |
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5.5 Laplace, Mellin and Fourier Mellin |
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203 | (5) |
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5.5.1 Laplace and Mellin transforms |
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203 | (1) |
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5.5.1.1 Laplace transform and basic systems analysis |
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203 | (2) |
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5.5.1.2 Mellin transform for scale invariance |
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205 | (2) |
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5.5.2 Fourier-Mellin transform |
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207 | (1) |
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208 | (1) |
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209 | (7) |
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5.7.1 Filter banks and signal analysis |
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209 | (1) |
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210 | (6) |
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216 | (1) |
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6 Applications of the Fourier Transform |
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217 | (36) |
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217 | (1) |
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218 | (4) |
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6.2.1 The continuous Fourier transform and Fourier optics |
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218 | (1) |
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6.2.2 Magnitude and phase, and beamforming |
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219 | (3) |
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6.3 Properties of the Fourier transform |
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222 | (10) |
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6.3.1 Superposition and fingerprint analysis |
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222 | (1) |
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6.3.2 Invariance and image texture analysis |
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222 | (5) |
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6.3.3 Invariance and image registration |
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227 | (1) |
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6.3.4 Differentiation and image feature extraction |
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228 | (1) |
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6.3.4.1 Template convolution and edge detection |
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228 | (3) |
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6.3.4.2 z-transform and Fourier analysis, and edge detection operators |
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231 | (1) |
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6.4 Processing signals using the Fourier transform |
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232 | (7) |
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6.4.1 Convolution theorem and ear biometrics |
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232 | (2) |
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6.4.2 Deconvolution and image enhancement |
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234 | (1) |
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6.4.3 Speech recognition and correlation |
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235 | (4) |
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6.5 The importance of phase and phase congruency |
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239 | (7) |
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6.6 Filtering and denoising, and image enhancement |
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246 | (2) |
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6.7 Variants of the Fourier transform, and coding |
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248 | (3) |
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251 | (2) |
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7 Who and What was Fourier? |
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253 | (10) |
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7.1 Nature and origins of the Fourier transform |
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253 | (5) |
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7.1.1 The basic nature and definitions of the Fourier transform |
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253 | (3) |
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7.1.2 On the development of the Fourier transform |
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256 | (2) |
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7.2 Baron Jean Baptiste Joseph Fourier |
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258 | (3) |
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261 | (2) |
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263 | (8) |
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8.1 Summary of Fourier transforms and thier variants |
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263 | (1) |
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8.2 Summary of properties of the continuous Fourier transform |
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264 | (1) |
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8.3 Continuous Fourier transform pairs |
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265 | (2) |
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8.4 Summary of properties of the discrete Fourier transform |
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267 | (1) |
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8.5 Discrete Fourier transform pairs |
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267 | (4) |
| References |
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271 | (8) |
| Index |
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279 | |