For example, the discrete-time Fourier transform and the Z-transform, from discrete time to continuous frequency, and the Fourier series, from continuous time to discrete frequency, are outside the class of discrete transforms.
Fourier transform | Laplace transform | Fast Fourier transform | Extract, transform, load | Hilbert transform | Fourier transform infrared spectroscopy | fast Fourier transform | Discrete cosine transform | transform | Mellin transform | discrete cosine transform | Bilinear transform | Z-transform | Y-Δ transform | Wavelet transform modulus maxima method | Hough transform | Gabor–Wigner transform | Gabor transform | fractional Fourier transform | Fourier transform spectroscopy | Fourier Transform | fast fourier transform | Discrete Hartley transform | Adaptive Transform Acoustic Coding (ATRAC) | Adaptive Transform Acoustic Coding |