The same codestream decoded six times, discarding 0–5 DWT resolution levels. Each discarded level halves the width and height and cuts block-decoding and inverse-DWT work to roughly a quarter; the whole file is still downloaded and passed to every decode. “N/A” means the codestream has fewer DWT levels than requested.
| Discarded DWT levels Decode time |
5
—
|
4
—
|
3
—
|
2
—
|
1
—
|
0
—
|
|---|