逆变换 Resources

Showing items tagged with "逆变换"

Image descriptions: A: Spectrum after Fourier transform; B: Spectrum after notch filter application; C: Filtered image after inverse transform (results not optimal). Ifft2: To validate the custom FFT program's correctness, used MATLAB's built-in ifft2 function for inverse transformation - output matches original image, confirming proper FFT implementation.

MATLAB 269 views Tagged

Speech signal denoising implementation in MATLAB environment, performing wavelet transform on noisy speech signals, applying threshold-based denoising principles, and reconstructing enhanced speech signals through inverse transformation with detailed algorithm explanation.

MATLAB 277 views Tagged

1. Select an image and perform DCT block operations (dividing image into 8×8 blocks, applying DCT transform to each block). 2. Use masking matrix for DCT coefficient region selection, perform inverse DCT to reconstruct original image, and calculate PSNR of synthesized image. 3. Choose a wavelet function to decompose an image, display transform coefficients to observe patterns, and perform inverse wavelet transform for image reconstruction.

MATLAB 243 views Tagged

MATLAB-based image enhancement implementation using Haar wavelet transform, featuring forward/inverse wavelet transforms with decomposition and reconstruction source code. The algorithm processes image data through multi-level wavelet decomposition, applies enhancement techniques to wavelet coefficients, and reconstructs the enhanced image.

MATLAB 189 views Tagged

Research on time-frequency characteristics of time series including Fourier transform and inverse transform, fast Mellin transform and inverse transform, short-time discrete Fourier transform for instantaneous frequency extraction. Implementation of time-frequency distributions: Born-Jordan distribution, Butterworth distribution, and Choi-Williams distribution for visualizing instantaneous frequency patterns.

MATLAB 227 views Tagged