# MEM -- In Memory Raster

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.

Memory datasets should support support for most kinds of auxilary information including metadata, coordinate systems, georeferencing, GCPs, color interpretation, nodata, color tables and all pixel data types.

## Dataset Name Format

It is possible to open an existing array in memory. To do so, construct a dataset name with the following format:

      MEM:::option=value[,option=value...]

For example:

      MEM:::DATAPOINTER=342343408,PIXELS=100,LINES=100,BANDS=3,DATATYPE=Byte,
           PIXELOFFSET=3,LINEOFFSET=300,BANDOFFSET=1

- 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)
- PIXELS: Width of raster in pixels. (required)
- LINES: Height of raster in lines. (required)
- BANDS: Number of bands, defaults to 1. (optional)
- DATATYPE: Name of the data type, as returned by GDALGetDataTypeName() (eg. Byte, Int16) Defaults to Byte. (optional)
- PIXELOFFSET: Offset in bytes between the start of one pixel and the next on the same scanline. (optional)
- LINEOFFSET: Offset in bytes between the start of one scanline and the next. (optional)
- BANDOFFSET: Offset in bytes between the start of one bands data and the next.

## Creation Options

There are no supported creation options.

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.