A map file may have zero, one or more OUTPUTFORMAT object declarations,
defining available output formats supported including formats like PNG,
GIF, JPEG, GeoTIFF, SVG, PDF and KML.
If OUTPUTFORMAT sections declarations are not found in the map file, the
following implicit declarations will be made. Only those for which support
is compiled in will actually be available. The GeoTIFF depends on building
with GDAL support, and the PDF and SVG depend on building with cairo support.
MIMETYPE "image/png; mode=8bit"
- DRIVER [name]
- The name of the driver to use to generate this output format. Some driver
names include the definition of the format if the driver supports multiple
formats. For AGG, the possbile driver names are “AGG/PNG” and “AGG/JPEG”.
For GD the possible driver names are “GD/Gif” and “GD/PNG”.
For output through OGR the OGR driver name is appended, such as
“OGR/Mapinfo File”. For output through GDAL the GDAL shortname for the
format is appended, such as “GDAL/GTiff”. Note that PNG, JPEG and GIF
output can be generated with either GDAL or GD (GD is generally more
efficient). TEMPLATE should be used for template based output. (mandatory)
- EXTENSION [type]
- Provide the extension to use when creating files of this type. (optional)
- FORMATOPTION [option]
Provides a driver or format specific option. Zero or more FORMATOPTION
statement may be present within a OUTPUTFORMAT declaration. (optional)
- AGG/*: “GAMMA=n” is used to specify the gamma correction to
apply to polygon rendering. Allowed values are [0.0,1.0] ,
default is 0.75. This value is used to prevent artifacts from
appearing on the border of contiguous polygons. Set to 1.0 to
disable gamma correction.
- AGG/JPEG: The “QUALITY=n” option may be used to set the quality of
jpeg produced (value from 0-100).
AGG/PNG: “COMPRESSION=n” is used to determine the ZLIB
compression applied to the png creation. n is expected to be an
integer value from 0 to 9, with 0 meaning no compression (not
recommended), 1 meaning fastest compression, and 9 meaning best
compression. The compression levels come at a cost (be it in
terms of cpu processing or file size, chose the setting that
suits you most). The default is COMPRESSION=6.
AGG/PNG supports quantizing from 24/32 bits to 8bits, in order
to reduce the final image size (and therefore save bandwidth)
(see also http://trac.osgeo.org/mapserver/ticket/2436#comment:4
for strategies when applying these options):
- “QUANTIZE_FORCE=on” used to reduce an RGB or RGBA image into
an 8bit (or less) paletted images. The colors used in the
palette are selected to best fit the actual colors in the RGB
or RGBA image.
- “QUANTIZE_COLORS=256” used to specify the number of colors to
be used when applying quantization. Maximum value is
256. Specifying anything between 17 and 255 is probably a
waste of quality as each pixel is still encoded with a full
byte. Specifying a value under 16 will produce tiny images,
but severly degraded.
“PALETTE=/path/to/palette.txt” is used to define the absolute
path where palette colors can be found. This file must contain
256 entries of r,g,b triplets for RGB imagemodes, or r,g,b,a
quadruplets for RGBA imagemodes. The expected format is one
triplet (or quadruplet) per line, each value separated by
commas, and each triplet/quadruplet on a single line. If you
want to use transparency with a palette, it is important to
have these two colors in the palette file: 0,0,0,0 and
0,0,0,0 is important if you have fully transparent areas.
255,255,255,255 is opaque white.
The important colors to have in your palette really depend
on your actual map, although 0,0,0,0 , 0,0,0,255 , and
255,255,255,255 are very likely to show up most of the
- “PALETTE_FORCE=on” is used to reduce image depth with a
predefined palette. This option is incompatible with the
previous quantization options. To allow additional colours
for anti-aliasing other than those in the predefined
palette, use with “QUANTIZE_COLORS”.
“METADATA_ITEM:option=value”: Additional PDF options can be
provided using the METADATA_ITEM prefix. The following
options are available: AUTHOR, CREATOR, CREATION_DATE,
KEYWORDS, PRODUCER, SUBJECT, TITLE.
FORMATOPTION "METADATA_ITEM:CREATOR=MapServer, with GDAL trunk"
FORMATOPTION "METADATA_ITEM:PRODUCER=MapServer, with GDAL trunk"
- GD/PNG: The “INTERLACE=[ON/OFF]” option may be used to turn
interlacing on or off.
- GD/GIF: The “INTERLACE=[ON/OFF]” option may be used to turn
interlacing on or off.
- GDAL/GTiff: Supports the “TILED=YES”, “BLOCKXSIZE=n”,
“BLOCKYSIZE=n”, “INTERLEAVE=[PIXEL/BAND]” and
“COMPRESS=[NONE,PACKBITS,JPEG,LZW,DEFLATE]” format specific
- GDAL/*: All FORMATOPTIONs are passed onto the GDAL create function.
Options supported by GDAL are described in the detailed documentation
for each GDAL format.
- GDAL/*: “NULLVALUE=n” is used in raw image modes (IMAGEMODE
BYTE/INT16/FLOAT) to pre-initialize the raster and an attempt is made
to record this in the resulting file as the nodata value. This is
automatically set in WCS mode if rangeset_nullvalue is set.
- OGR/*: See the OGR Output document for details of OGR
- IMAGEMODE [PC256/RGB/RGBA/INT16/FLOAT32/FEATURE]
Selects the imaging mode in which the output is generated. Does matter
for non-raster formats like Flash. Not all formats support all
combinations. For instance GD supports only PC256. (optional)
- PC256: Produced a pseudocolored result with up to 256 colors in
the palette (legacy MapServer mode). Only supported for GD/GIF
- RGB: Render in 24bit Red/Green/Blue mode. Supports all colors
but does not support transparency.
- RGBA: Render in 32bit Red/Green/Blue/Alpha mode. Supports all
colors, and alpha based transparency. All features are rendered
against an initially transparent background.
- BYTE: Render raw 8bit pixel values (no presentation). Only
works for RASTER layers (through GDAL) and WMS layers currently.
- INT16: Render raw 16bit signed pixel values (no presentation).
Only works for RASTER layers (through GDAL) and WMS layers currently.
- FLOAT32: Render raw 32bit floating point pixel values
(no presentation). Only works for RASTER layers (through GDAL)
and WMS layers currently.
- FEATURE: Output is a non-image result, such as features written
via templates or OGR.
- MIMETYPE [type]
- Provide the mime type to be used when returning results over the web.
- NAME [name]
- The name to use in the IMAGETYPE keyword of the map file to
select this output format. This name is also used in metadata describing
wxs formats allowed, and can be used (sometimes along with mimetype) to
select the output format via keywords in OGC requests. (optional)
- TRANSPARENT [ON/OFF]
- Indicates whether transparency should be enabled for this format. Note
that transparency does not work for IMAGEMODE RGB output. Not all formats
support transparency (optional). When transparency is enabled for the
typical case of 8-bit pseudocolored map generation, the IMAGECOLOR color
will be marked as transparent in the output file palette. Any other map
components drawn in this color will also be transparent, so for map
generation with transparency it is best to use an otherwise unused color
as the background color.