For raster images, GeoExpress can create compressed images in the MrSID and JPEG 2000 formats. Because the NITF format can contain JPEG 2000 files, you can also create compressed NITF files. For LiDAR data, GeoExpress can create compressed files in the MrSID and LAZ formats. For LiDAR data, LAZ files can only be created using lossless compression. MrSID files are lossless by default, but you can also specify a compression ratio to create lossy files.
To see information about an image, including the file format, width, height, and compression ratio if applicable, use the mrsidgeoinfo tool.
The following table compares some of the features supported by the raster output formats:
output format | ||||
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Feature | MG2 | MG3 | MG4 | JPEG 2000 |
Lossy output with a maximum of 3 bands, cropping, no advanced encoding, output file smaller than 2GB |
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Advanced encoding (such as reprojection, color balancing, despeckling, and Area of Interest encoding) |
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Output file size larger than 2GB |
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Lossless output |
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Mosaic that uses MrSID files as input |
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Multispectral output |
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Arbitrary band mapping |
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Per-band compression |
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The following table compares some of the features supported by the LiDAR output formats:
output format | ||||
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Feature | LAZ | LAS | BPF | MG4 |
Lossless compression |
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Using a specified compression ratio |
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Creating mosaics |
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For more information on output formats, see Supported output file formats.