PCI Geomatics Database File (PCIDSK) Reader/Writer
Licensing options for this format begin with FME Professional Edition.
The PCIDSK Reader/Writer allows FME to access data in the PCI Geomatics Database File format.
Overview
PCI Geomatics developed the PCIDSK format, also known as the PCI Geomatics Database File Format, in 1988 as a replacement for the outdated and importable UNIDSK format. The old UNIDSK format was dependent on the 16-bit architecture of the PDP11 system and was unable to scale to the 32-bit or 64-bit systems that replaced it. In addition to adding portability, the redesign of the old UNIDSK format incorporated other advantageous features:
- Expandability: From the start, the PCIDSK format was designed to accommodate new requirements as they emerged. Fields have been reserved to allow for growth and the segmented design accepts new feature types.
- Access Speed: Using a 512KB block design, which is the block size used by most hard drives, you can read and write to sections of the image with minimal overhead at the disk and operating system level.
GCPs (ground control points) present along with a projection in an PCIDSK file being read can either be applied to the data as an affine transformation, or stored as properties of the raster geometry. GCPs cannot be written to PCIDSK.
Reader Overview
FME considers a single PCIDSK file to be a dataset. The PCIDSK file contains pixel data. Each pixel in the file is a point in a single FME raster feature.
Writer Overview
FME considers a dataset to be a folder name. The PCIDSK writer distinguishes duplicate output files by appending numbers to the filenames.
FME Raster Features
FME raster features represent raster data and use several concepts that are unlike those used in the handling of vector data. The topics below describe how FME processes raster data.
PCIDSK supports rasters with an arbitrary number of bands, provided all bands are the same data type and no band has a palette.