Table 1. Effects of SS-DWT on lossless JPEG 2000 bitrates for step-skip decisions selected by the BH and a couple of its variants.
| Heuristic variant | Images | ||||
|---|---|---|---|---|---|
| Photo | No-photo | No-photo(a) | No-photo(b) | All | |
| r DWT | 3.9975 | 2.9162 | 3.2882 | 2.7348 | 3.6395 |
| ΔrBH(0) | -0.01% | -7.08% | -21.59% | 0.00% | -2.35% |
| ΔrBH(1) | -0.75% | -15.25% | -32.26% | -6.96% | -5.55% |
| ΔrBH(2) | -0.86% | -15.66% | -32.28% | -7.54% | -5.76% |
| ΔrBH(3) | -0.86% | -15.66% | -32.28% | -7.55% | -5.76% |
| ΔrBH(4) | -0.86% | -15.66% | -32.28% | -7.55% | -5.76% |
| ΔrBH_TR(1) | -0.75% | -15.28% | -32.30% | -6.98% | -5.56% |
| ΔrBH_TR(2) | -0.86% | -15.69% | -32.33% | -7.57% | -5.77% |
| ΔrBH_AR(1) | -0.73% | -13.24% | -27.26% | -6.40% | -4.87% |
| ΔrBH_AR(2) | -0.74% | -13.38% | -27.59% | -6.44% | -4.93% |
| ΔrBH_PW(1) | -0.31% | -9.26% | -23.35% | -2.38% | -3.27% |
| ΔrBH_PW(2) | -0.31% | -9.29% | -23.43% | -2.40% | -3.28% |
rDWT−average lossless JPEG 2000 bitrate for 3-level unmodified DWT (bpp); Δrvariant−average SS-DWT bitrate change obtained with use of the heuristic variant: BH–basic heuristic, BH_TR–heuristic with additional testing if doing the reorder step improves bitrate, BH_AR–heuristic with disabled skipping of the reorder step, BH_PW–heuristic that for each pair of complementary subbands either skips all 3 DWT steps or performs them all.