Licensing options for this format begin with FME Desktop Professional Edition.
The PNG Reader/Writer module allows FME to access data in PNG format.
Overview
The PNG (Raster) Reader/Writer module provides raster writing, rather than vector-to-raster writing.
PNG (Portable Network Graphics) is an image format that supports a wide range of classified and continuous color models.
The PNG format can only support up to 256 palette colors as a classified image, but can support both 1- and 2-byte RGB, RGBA, and greyscale continuous images.
The format was introduced in 1995 as a replacement format for GIF, specifically implemented so that it does not require a patent to use compression.
Reader Overview
FME considers a single PNG file to be a dataset. The PNG file contains pixel data, and 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.
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.
PNG files can only be written with square pixel dimensions.
PNG supports rasters with the following band structures:
- Red, Green, Blue
- Red, Green, Blue, Alpha
- Gray
- Gray, Alpha
- UInt8 with an RGBA32 palette