1 | Transform and inverse transform have to be normalized in both directions such that if the transform coefficients are scaled by 1/s the inverse transform has to be scaled by s. This leaves the freedom for selection of s through all scales . Quality (PSNR- the highest the better) can be affected, since relative band magnitudes are then differently quantized. The same effect for DCT has not been exploited. |
2 | For Lenna: |
3 | We search for automatic selection criterion (and even for band specific s). |
4 | Hor Ver PSNR Hor Ver PSNR Hor Ver PSNR Hor Ver PSNR Hor Ver PSNR |
5 | 0.50 0.67 27.7 0.50 0.80 27.9 0.50 1.00 28.1 0.50 1.25 27.2 0.50 1.5 27.0 |
6 | 0.57 0.67 - 0.57 0.80 30.1 0.57 1.00 29.7 0.57 1.25 29.1 0.57 1.5 28.7 |
7 | 0.60 0.67 - 0.67 0.80 30.3 0.67 1.00 30.5 0.67 1.25 30.2 0.67 1.5 30.4 |
8 | 0.80 0.67 30.4 0.80 0.80 30.4 0.80 1.00 31.2 0.80 1.25 30.6 0.80 1.5 30.7 |
9 | 1.00 0.67 30.6 1.00 0.80 30.2 1.00 1.00 30.5 1.00 1.25 30.7 1.00 1.5 30.3 |
10 | 1.25 0.67 29.9 1.25 0.80 29.9 1.25 1.00 29.7 1.25 1.25 30.1 1.25 1.5 29.7 |
11 | 1.50 0.67 29.7 1.50 0.80 29.1 1.50 1.00 29.2 1.50 1.25 29.7 1.50 1.5 28.8 |
12 | 1.75 0.67 28.6 1.75 0.80 28.6 1.75 1.00 28.8 1.75 1.25 28.4 1.75 1.5 28.6 |
13 | 2.00 0.67 28.3 2.00 0.80 28.7 2.00 1.00 28.1 2.00 1.25 28.4 2.00 1.5 28.3 |