Compressing Elevation Data
نویسنده
چکیده
This paper compares several, text and image, lossless and lossy, compression techniques for regular gridded elevation data, such as DEMs. Sp compress and progcode, the best lossless methods average 2.0 bits per point on USGS DEMs, about half the size of gzipped files, and 6.2 bits per point on ETOPO5 samples. Lossy compression produces even smaller files at moderate error rates. Finally, some technques for compressing TINs will be introduced.
منابع مشابه
Elevation Data Operations
We describe several past and proposed projects for converting elevation data to different formats, such as gridded, TIN, and spline, lossily compressing, applying to visibility and drainage to test the compression quality, and integrating everything into a test suite.
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