The topics below describe how FME processes raster data.
#Er mapper ecw compressor download professional
FME Raster FeaturesįME raster features represent raster data and use several concepts that are unlike those used in the handling of vector data. ER Mapper Professional is a powerful, yet simple to use, geospatial imagery processing application. It distinguishes duplicate output files by appending numbers to the filenames. The writer creates and writes data into a single folder specified by the Dataset parameter. The ECW file contains pixel data, and each pixel in the file is a point in a single FME raster feature. Reader OverviewįME considers a single ECW file to be a dataset. Although this compression still does not guarantee the exact copy of the source file, the output will be very close to the original. If you know that source data comes from files with lossy compression, you should also set the compression level to 0. In addition, Workbench may not know which format data comes from, and whether it used lossy compression. Note: Repeatedly reading and saving files may decrease the quality for this format. ERDAS ER Mapper allows you to visualize, enhance and combine images for a broad array of applications. Also note that ECW does not support lossless compression that is, even if a compression level of 0 is specified, the output ECW file may not be identical to the original image. ER Mapper Ecw Display - ECW - Mapper - ER Mapper - OR Mapper. Note: This value only represents the targeted compression level, and this may not actually be achieved. The compressed formats use ECW (Enhanced Compressed Wavelet) and JPEG 2000 compression to make the output image file size considerably smaller than the original. This is expressed as a percentage of the original file size for example, setting a compression level of 75 means that the output image will be approximately 75% smaller than an uncompressed image (that is, it will be about one-quarter the size of the uncompressed image). The ECW writer supports the following option:Ĭompression Level: This option sets the desired compression level of the output image. GCPs (ground control points) present along with a projection in an ECW file being read can either be applied to the data as an affine transformation, or stored as properties of the raster geometry. Coordinate system and georeferencing transformations are read, but in some cases coordinate systems may not translate. Many less common coordinate systems may not be mapped properly when writing to ECW files. The ECW technique also takes advantage of CPU, L1 and L2 levels of cache to do its linear and unidirectional data flow through the Discrete Wavelet Transformations (DWT) process. Any non-eight-bit source data returns an error. However, any image saved in this format must be at least 128 x 128 pixels.
There is no inherent limitation to image size in the compression technology. The ECW image format is used to compress very large images, without using intermediate tiling or intermediate disk storage. Licensing options for this format begin with FME Professional Edition.įME provides reader and writer access to data in ER Mapper’s Compressed Wavelet (ECW) format.
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