Purpose
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Specifies if the raster image will be stored in a file as a compressed raster image.
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Return value
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Returns SUCCEED (or 0) if successful and FAIL (or -1) otherwise.
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Description
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GRsetcompress specifies if the raster image specified by the parameter ri_id will be stored in the file in compressed format.
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The compression method is specified by the parameter comp_type. Valid values of the parameter comp_type are:
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COMP_CODE_NONE (or 0) for no compression
COMP_CODE_RLE (or 1) for RLE run-length encoding
COMP_CODE_SKPHUFF (or 3) for Skipping Huffman compression
COMP_CODE_DEFLATE (or 4) for GZIP compression
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The compression method parameters are specified by the parameter c_info in C and the parameter comp_prm in Fortran. The parameter c_info has type comp_info, which is described in the hcomp.h header file. It contains algorithm-specific information for the library compression routines.
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The skipping size for the Skipping Huffman algorithm is specified in the field c_info.skphuff.skp_size in C and in the parameter comp_prm(1) in Fortran.
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The deflate level for the GZIP algorithm is specified in the field c_info.deflate.level in C and in the parameter comp_prm(1) in the Fortran.
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