NDWasmSignal

Namespace

NDWasmSignal

Description:
  • NDWasmSignal: Signal Processing & Transformations Handles O(n log n) frequency domain transforms and O(n^2 * k^2) spatial filters.

Source:

Methods

(static) conv2d(img, kernel, stride, padding) → {NDArray}

Description:
  • 2D Spatial Convolution. Complexity: O(img_h * img_w * kernel_h * kernel_w)

Source:
Parameters:
Name Type Description
img NDArray

2D Image/Matrix.

kernel NDArray

2D Filter kernel.

stride number

Step size (default 1).

padding number

Zero-padding size (default 0).

Returns:

Convolved result.

Type
NDArray

(static) correlate2d(img, kernel, stride, padding) → {NDArray}

Description:
  • 2D Spatial Cross-Correlation. Similar to convolution but without flipping the kernel. Complexity: O(img_h * img_w * kernel_h * kernel_w)

Source:
Parameters:
Name Type Description
img NDArray

2D Image/Matrix.

kernel NDArray

2D Filter kernel.

stride number

Step size.

padding number

Zero-padding size.

Returns:

Cross-correlated result.

Type
NDArray

(static) dct(a) → {NDArray}

Description:
  • 1D Discrete Cosine Transform (Type II). Complexity: O(n log n)

Source:
Parameters:
Name Type Description
a NDArray

Input signal.

Returns:

DCT result of same shape.

Type
NDArray

(static) fft(a) → {NDArray}

Description:
  • 1D Complex-to-Complex Fast Fourier Transform. The input array must have its last dimension of size 2 (real and imaginary parts). The transform is performed in-place. Complexity: O(n log n)

Source:
Parameters:
Name Type Description
a NDArray

Complex input signal, with shape [..., 2].

Returns:
  • Complex result, with the same shape as input.
Type
NDArray

(static) fft2(a) → {NDArray}

Description:
  • 2D Complex-to-Complex Fast Fourier Transform. The input array must be 3D with shape [rows, cols, 2]. The transform is performed in-place. Complexity: O(rows * cols * log(rows * cols))

Source:
Parameters:
Name Type Description
a NDArray

2D Complex input signal, with shape [rows, cols, 2].

Returns:
  • 2D Complex result, with the same shape as input.
Type
NDArray

(static) ifft(a) → {NDArray}

Description:
  • 1D Inverse Complex-to-Complex Fast Fourier Transform. The input array must have its last dimension of size 2 (real and imaginary parts). The transform is performed in-place. Complexity: O(n log n)

Source:
Parameters:
Name Type Description
a NDArray

Complex frequency-domain signal, with shape [..., 2].

Returns:
  • Complex time-domain result, with the same shape as input.
Type
NDArray

(static) ifft2(a) → {NDArray}

Description:
  • 2D Inverse Complex-to-Complex Fast Fourier Transform. The input array must be 3D with shape [rows, cols, 2]. The transform is performed in-place.

Source:
Parameters:
Name Type Description
a NDArray

2D Complex frequency-domain signal, with shape [rows, cols, 2].

Returns:
  • 2D Complex time-domain result, with the same shape as input.
Type
NDArray

(static) rfft(a) → {NDArray}

Description:
  • 1D Real-to-Complex Fast Fourier Transform (Optimized for real input). The output is a complex array with shape [n/2 + 1, 2]. Complexity: O(n log n)

Source:
Parameters:
Name Type Description
a NDArray

Real input signal.

Returns:
  • Complex result of shape [n/2 + 1, 2].
Type
NDArray

(static) rifft(a, n) → {NDArray}

Description:
  • 1D Complex-to-Real Inverse Fast Fourier Transform. The input must be a complex array of shape [k, 2], where k is n/2 + 1.

Source:
Parameters:
Name Type Description
a NDArray

Complex frequency signal of shape [n/2 + 1, 2].

n number

Length of the original real signal.

Returns:

Real-valued time domain signal.

Type
NDArray