Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Process time, resolution, and tile numbers that corresponding to different zoom level
| Zoom level | Process time (MS) | Resolution (m) | Tile number |
|---|---|---|---|
| 17 | 1190 | 256.42 | 1954 |
| 18 | 1229 | 128.21 | 2880 |
| 19 | 1338 | 64.105 | 4722 |
| 20 | 1561 | 32.05 | 8497 |
| 21 | 1998 | 16.03 | 16,751 |
| 22 | 3408 | 8.01 | 42,562 |
| 23 | 15,230 | 4.00 | 178,946 |
