FourierDCTFilter[image, t]
reduces noise in image by locally thresholding the discrete cosine transforms of overlapping subimages, using the hard threshold t.


  • FourierDCTFilter works with arbitrary grayscale and multichannel images.
  • Local DCT thresholding is applied to all overlapping 16×16 partitions of image. The value of each output pixel is the average of the corresponding pixel in all partitions that include the pixel.
  • For multichannel images, color channels are decorrelated by effectively using a 3D DCT.
  • In FourierDCTFilter[image, t], the threshold value t is typically in the range 0 to 1.

ExamplesExamplesopen allclose all

Basic Examples (2)Basic Examples (2)

Denoise a color image:

Click for copyable input

Denoise a grayscale image:

Click for copyable input
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