Howtosignalprocessing
Is A DCT Matrix Symmetric?
The DCT-IV matrix becomes orthogonal (and thus, being clearly symmetric, its own inverse) if one further multiplies by an overall scale factor of. A variant of the DCT-IV, where data from different transforms are overlapped, is called the modified discrete cosine transform (MDCT).
Why is DFT symmetric?
And without going into mathematical details, DFT of real valued function is symmetric, i.e. resultant Fourier function has both real and imaginary parts which are mirror images with respect to 0 frequency component.
How does DCT work in image processing?
DCT is used in the JPEG image compression algorithm. The input image is divided into 8-by-8 or 16-by-16 blocks, and the two-dimensional DCT is computed for each block. The DCT coefficients are then quantized, coded, and transmitted.
