# readers.gdal

The GDAL reader reads GDAL readable raster data sources as point clouds.

Each pixel is given an X and Y coordinate (and corresponding PDAL dimensions) that are center pixel, and each band is represented by “band-1”, “band-2”, or “band-n”. The user must know what the bands correspond to, and use filters.ferry to copy data into known Dimensions as needed.

Note

filters.ferry is needed to map GDAL output to typical Dimensions names. For output to formats such as LAS, this mapping is required.

Default Embedded Stage

This stage is enabled by default

## Basic Example

Simply writing every pixel of a JPEG to a text file is not very useful.

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    {
      "pipeline":[
        {
          "type":"readers.gdal",
          "filename":"./pdal/test/data/autzen/autzen.jpg"
        },
        {
          "type":"writers.text",
          "filename":"outputfile.txt"
        }
      ]
    }

## LAS Example

The following example assigns the bands from a JPG to the RGB values of an ASPRS LAS file using writers.las.

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    {
      "pipeline":[
        {
          "type":"readers.gdal",
          "filename":"./pdal/test/data/autzen/autzen.jpg"
        },
        {
          "type":"filters.ferry",
          "dimensions":"band-1=Red, band-2=Green, band-3=Blue",
        },
        {
          "type":"writers.text",
          "filename":"outputfile.txt"
        }
      ]
    }

## Options

filename
  GDALOpen ‘able raster file to read [Required]

count
  Maximum number of points to read [Optional]