| | 40 | |
| | 41 | We now have per-pixel geolocation information in the required projection. The next and final stage of the mapping procedure is to resample the level 1 data into a regular grid based on the projection information. |
| | 42 | |
| | 43 | The two things we need to decide on are: |
| | 44 | * what is a suitable pixel size for the output grid? |
| | 45 | * which of the bands do we wish to map? |
| | 46 | |
| | 47 | We can use the [http://arsf-dan.nerc.ac.uk/pixelsize/pixelsize.html pixel size estimator] to get an idea of the approximate spatial resolution of the data or we can use a different size if we wish. Let us say we want to map using square pixels with 2 metres resolution to match up with some external data we have. |
| | 48 | |
| | 49 | If we wish to map all bands of the level 1 data, and write the data to a file named {{{flightline1_mapped.bil}}} then we can use a command such as: |
| | 50 | |
| | 51 | {{{ |
| | 52 | aplmap -igm my_outputs/flightline1_utm31.igm -lev1 flightlines/level1b/flightline1.bil -mapname my_outputs/flightline1_mapped.bil -pixelsize 2 2 -bandlist ALL |
| | 53 | }}} |
| | 54 | |
| | 55 | Or if we only want to map a selection of bands, say bands 100 to 150 inclusive, we can use a command such as: |
| | 56 | |
| | 57 | {{{ |
| | 58 | aplmap -igm my_outputs/flightline1_utm31.igm -lev1 flightlines/level1b/flightline1.bil -mapname my_outputs/flightline1_mapped.bil -pixelsize 2 2 -bandlist 100-150 |
| | 59 | }}} |