How to calculate the Compression ratio of Wavelet transformed image??

Hi,
I'm working with image compression with wavelet transform using different types of wavelets in MATLAB.I did multi-resolution decomposition and reconstructed the image.I've calculated the PSNR and MOS. I didn't encode the image into file.Is it possible to calculate the compression ratio without encoding (like in DCT) ? If, then whats the procedure?

If anyone has any idea plz share it with me and ur cooperation will be highly appreciated.

Thanking u,
Razib, Siam Start a New Thread