Electronic Circuits and Projects Forum

Hi,

You might want to look into the Jpeg standard for image compression. The image information is transformed into frequency components in two dimensions, and that is the data that is actually stored, not the picture raw 'signal' itself. On decompression, the frequency components are transformed back into the 'time' components and that gets displayed as a very close approximation of the original picture.

Hi,

I suppose you could if you felt like going through all that trouble. You'd have to figure out if it has any benefit in the long run.

There is wavelet compression which is 'supposed' to be better, and there is always fractal compression which im not sure ever made it off the ground too far yet.

Jpeg uses the discrete cosine transform in two dimensions for the conversions, although it's often implemented as a FFT to make it faster with some required matrix transforms and a few constants.

ok i will study wavelet compression and fractal compression.
I just googled and i see that Digital Radio already exist LoL

one more Question that can we use any orthogonal periodic functions in Fourier transform. instead of sine and cosine

Hi,

Yes the wavelet is used in modern image processing. I've never used it myself actually, but did do a custom FFT to DCT for a Jpeg decoder long time ago.

If you use something other than sine and cosine then you dont have a Fourier anymore :-)
You can use powers of x too, but im sure there are a ton of other ways to encode a signal.