Appendix A: Compression Rates and File Size
zLidar files are typically about 18% of the size of the equivalent LAS files and about 52% larger than the equivalent LAZ files. The following table presents a comparison of zLidar file size with LAS and LAZ files for a number of multi-tile data sets of varying sizes.
Table A.1. Comparison of LiDAR data format files sizes in gigabytes for sample data sets.
| Dataset | Tiles | Points | LAS (GB) | LAZ (GB) | zLidar (GB) |
|---|---|---|---|---|---|
| Alberta Site | 64 | 4.118x108 | 12.17 | 1.28 | 2.16 |
| Bowmanville | 49 | 6.282x108 | 18.85 | 2.48 | 3.63 |
| Broughton's Creek | 332 | 4.433x108 | 12.4 | 1.2 | 1.9 |
| Gully Creek | 109 | 3.244x108 | 9.08 | 1.08 | 1.64 |
| LAR | 13,270 | 1.033x1011 | 2892.8 | 417.29 | 697.09 |
| McGregor Creek | 794 | 8.751x109 | 262.54 | 26.19 | 37.65 |
| Ottawa 2015 | 661 | 1.005x1010 | 281.30 | 49.19 | 66.10 |
| Rondeau Bay 2012 | 586 | 1.141x109 | 31.95 | 3.34 | 5.08 |
| Rondeau Bay 2018 | 953 | 1.014x1010 | 304.19 | 29.88 | 44.16 |