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<title>MEM -- In Memory Raster</title>
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<h1>MEM -- In Memory Raster</h1>
GDAL supports the ability to hold rasters in a temporary in-memory format.
This is primarily useful for temporary datasets in scripts or internal
to applications. It is not generally of any use to application end-users.<p>
Memory datasets should support for most kinds of auxilary information
including metadata, coordinate systems, georeferencing, GCPs,
color interpretation, nodata, color tables and all pixel data types.<p>
<h2>Dataset Name Format</h2>
It is possible to open an existing array in memory. To do so, construct
a dataset name with the following format:
<pre>
MEM:::option=value[,option=value...]
</pre>
For example:
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MEM:::DATAPOINTER=342343408,PIXELS=100,LINES=100,BANDS=3,DATATYPE=Byte,
PIXELOFFSET=3,LINEOFFSET=300,BANDOFFSET=1
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<ul>
<li> DATAPOINTER: pointer to the first pixel of the first band represented as
a long integer. NOTE! This may not work on platforms where a long is 32 bits and a pointer is 64 bits. (required)
<li> PIXELS: Width of raster in pixels. (required)
<li> LINES: Height of raster in lines. (required)
<li> BANDS: Number of bands, defaults to 1. (optional)
<li> DATATYPE: Name of the data type, as returned by GDALGetDataTypeName() (eg. Byte, Int16) Defaults to Byte. (optional)
<li> PIXELOFFSET: Offset in bytes between the start of one pixel and the next on the same scanline. (optional)
<li> LINEOFFSET: Offset in bytes between the start of one scanline and the next. (optional)
<li> BANDOFFSET: Offset in bytes between the start of one bands data and the next.
</ul>
<h2>Creation Options</h2>
There are no supported creation options.<p>
The MEM format is one of the few that supports the AddBand() method.
The AddBand() method supports DATAPOINTER, PIXELOFFSET and LINEOFFSET
options to reference an existing memory array.<p>
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