Follow

What File Format Should I Export from Surfer?

Surfer supports exporting to many different file formats. When exporting data from Surfer for use either in another software package (either another Golden Software package or a third-party application), for inserting into a publication, or for any other purpose, the multitude of supported file formats can be confusing. It may not always be clear when you should be using the Golden Software file types (e.g. BLN, GSB, GSI, etc) or another file format (e.g. DXF, SHP, MIF), or when you need another file format altogether.

There are three main types of files you can export or save from Surfer: grid files, data files, and base map files. The base map file formats can be further subdivided into three types, raster image, vector and metafile formats. Which format you choose to export depends on what you are exporting, and what you want to do with the exported data.

1. Grid Files
(e.g. ADF, ASC, DEM, GRD)
Dickenson FileFormatSurferImage1
2. Data Files
(e.g., CSV, DAT, TXT, XLSX)
Dickenson FileFormatSurferImage2
3. Base Map Files  
    3a. Raster Image
    (e.g. BMP, JPG, GeoTIFF, TIF)
Dickenson FileFormatSurferImage3
    3b. Vector
    (e.g. E00, DXF, KML, MIF, SHP)
Dickenson FileFormatSurferImage4
    3c. Metafile
    (e.g. EMF, WMF)
Dickenson FileFormatSurferImage5
Surfer can export data as grid files, data files, and base map files.
 

Grid and data file formats are fairly self-explanatory with little variation in the content in these files. This article will not focus on these formats, but give some brief information:

  • Grid files contain XY extents in map units, grid spacing, Z values at grid nodes (or grid cell centers, depending on the grid file format), and null values. There is not much variation in the information saved to these types of files. You could save a grid from Surfer to create contours, watersheds, or other map types in Surfer or other applications, or perform other grid calculations such as math or volume operations. The X, Y and Z information is the same in all grid formats, so the format you choose depends on the supported file formats of the program with which the grid will be used. For example, if you work primarily in Surfer, save grids in the default Surfer grid file format. If you want to bring the grids into ArcMap for display, save the grids in one of the supported ESRI grid formats (e.g. ADF, ASC or FLT).
  • Data files contain raw data. Data files can be Excel spreadsheets, TXT or other ASCII data files. They can contain XY information along with Z values, labels, or other data. Again, there is not much variation as all of the data files contain the same basic information. You can save a data file from the Surfer worksheet in many different formats, including CSV, DAT or XLSX. The data saved will be the same in all formats. The only formats that may have a difference are the Excel formats if you have many thousands of rows of data. This is because the Excel formats are limited to a certain number of rows and columns:
    • XLS file format is limited to a 65536 rows and 256 columns
    • XLSX is limited to 1,048,576 rows and 16,384 columns

This article will focus primarily on the variations in the various base map file formats. As mentioned previously, the base map file formats can be further subdivided into three types: raster image files, vector files, and metafiles.

Raster Image Files

Raster images are images of exactly what you see on the screen. This type of file is a good option for sending a picture of the map to a colleague, inserting the image into a report or presentation, uploading the image to a website, or sending the image to a publication for print. This is also a good choice if you need a georeferenced image to overlay with other map types either in Surfer or other applications. Normally individual elements are not editable in raster image file formats. So, line styles, line widths and text properties are not editable. Some options, such as color, are editable using image processing software.

Similar to grid and data files, there is little variation in the actual content of these files. A picture of what is in your Surfer project file is exported. The main differences between formats are some of the format-specific options. Which format you choose depends on if you need compression, background transparency, or what format you are required to provide (if you are going to use it in another application or for publication).

All the image export formats support options for setting the pixel size, resolution (e.g. dpi), document size, and color format for the exported image. In addition, all image formats have the option to include spatial reference information, such as real world XY coordinates and coordinate system (e.g. projection/datum) information.

The spatial reference information can be saved in a number of formats, including an internal only format (e.g. GeoTIFF), or in external files, such as:

  • Blue Marble .RSF file
  • ESRI World file (.xxW)
  • ESRI .PRJ file
  • Golden Software Reference (.GSR and .GSR2) files

 

Note that the Blue Marble RSF and ESRI World files only contain XY coordinate information. They do not contain any coordinate system information. Likewise, the ESRI PRJ files only contain coordinate system information and no XY coordinate referencing. Golden Software Reference files contain both real world XY coordinate and coordinate system information.

The following table summarizes the format specific options and provides hints, tips, and cautions for each of the raster image file formats available to export from Surfer.

File Extension
Name
Format-Specific Options
Comments
BMP
Windows Bitmap
(BMP)
none
This is the largest of the raster image export files because there are no compression options.
EPS
Encapsulated
Postscript
embedded
preview
This is a raster only EPS.
GIF
GIF Image
transparency
This is a good small-size format for exporting imagery with background transparency. GIF files are limited to a resolution of 72 dpi.
JP2, J2K,
JPC, JPT,
JPEG2000,
J2000
JPEG-2000 Bitmap
compression and
container format
This is a compressed image format with similar properties to JPG, but with greater compression due to container format. The container format reduces the file size without degrading the image.
JPG, JPEG
JPEG Compressed Bitmap
compression
This is a compressed image format. You can often obtain a nice quality image at a small size with the compression. The more you compress the image, the more the quality of the image is degraded.
PDF
PDF (Raster)
compression
This format is useful when required to have a PDF (either for distribution or publication) and the vector format PDF is not sufficient.
PNG
Portable Network Graphics
transparency
This format is often used when transparent backgrounds are required. The file sizes are small, so these are great for publication on the web.
PNM
PNM Image
none
 
RAS, SUN
Sun Raster Image
none
This format is common for sharing images between Windows and Unix machines.
RGB, RGBA
SGI-RGB Image
none
This format is also common for sharing images between Windows and Unix machines.
TGA
Targa (TrueVision)
none
 
TIF
Tagged Image and GeoTIFF
compression, format
This is the most commonly exported image file format. GeoTIFFs (TIFs exported with the spatial reference information saved in an internal format) are used widely in other software packages. High resolution TIF images (>=300 dpi) are often exported for print publication.
X, XIMG
AVS X-Image
none
This format is common for sharing images between Windows and Unix machines.
This is a list of the raster image file formats available for export from Surfer. All formats support options for
image size, resolution, color format and spatial referencing inclusion (real world maps units and coordinate system
information). Some image formats also offer their own additional export options, such as the ability to compress
the image, apply the background transparency, or include a small preview image. These options are
listed in the Format-Specific Options column in the table above.

Vector Files

Vector files contain separate object entities. There is a wide range of vector format types available. Each type contains different information. For example, some formats contain color information, while others do not. Some contain coordinate information, while others do not. Some formats support text and imagery, and others do not. The table below clarifies some ambiguity in these file formats and provides hints, tips and cautions for the various formats. The format you ultimately export depends on what type of data you need and what other application you are going to use the file.

All the vector export formats below support the option to include spatial reference information. Real world XY coordinates can be stored in the file itself. Coordinate system (e.g. projection/datum) information can be stored either internally (e.g. GSB), or in external files such as:

  • ESRI .PRJ file
  • Golden Software Reference (.GSR and .GSR2) files
 

Note that ESRI PRJ, GSR and GSR2 files for vector file export only contain coordinate system information and no XY coordinate referencing.

File Extension
Name
Format-Specific Options
Supported Items
(Text, Images, Drawing Properties, Attributes, Contour Line Z Values)
Comments
Best Format to Use With
BLN
Golden Software Blanking
Break apart compound areas
Attributes
Contour Z value
(File | Export)
A BLN file is a simple boundary file format for points, polylines and polygons. Each object can have one text attribute. This format is used mostly in Surfer for blanking grids, defining fault or breakline traces during gridding, defining the line of section for slicing grids, or for loading as base layers. This is a text format with one simple header row per object, so this format can also be used for exporting XY values.
Surfer for grid functions (blanking, slicing, gridding with faults/breaklines) and simple boundaries Golden Software applications
BNA
Atlas Boundary
Break apart compound areas
Attributes
Contour Z value
(File | Export)
A BNA file is a simple boundary file format for points, polylines and polygons. Each object can have two attributes.
Other mapping applications
DXF
AutoCAD DXF Drawing
File format version
ASCII vs. binary format
Color mapping
Drawing options
Text
Images
Some Drawing Properties
Contour Z value (Map |Export Contours)
DXF files are a good format choice when transferring data from Surfer to another application. DXF files can contain points, polylines, polygons, text, and can reference imagery and retain most drawing properties. However, no attributes are exported for features in base layers. Most other mapping or drawing applications can read DXF files.
Other mapping applications
CAD applications
GSB
Golden Software Boundary
Break apart compound areas
File format version
Attributes
Contour Z value (File | Export)
This is another simple boundary file format for points, polylines and polygons. Coordinates, coordinate system and attribute information is saved internally.
Golden Software applications
GSI
Golden Software Interchange
Write areas as curves
Render text
Render marker symbols
Text
Images
Drawing Properties
Attributes
Contour Z value (File | Export)
The GSI format is best used when exchanging information between Surfer projects or Golden Software applications (e.g. between MapViewer and Surfer). Virtually all properties of the map are retained.
Golden Software applications
KML/KMZ
Goodle Earth
Text options
Marker options
Area options
Curve options
Line widths
Split compound areas
Text
Images
Drawing Properties
Contour Z value (File | Export)
KML/KMZ formats are best used when transferring map data from Surfer to Google Earth. The KMZ format is the compressed version of KML, so the file size may be slightly smaller. KML/KMZ files are required to be in lat/long units. If your map is not in lat/long units, then a coordinate system must be specified and Surfer will convert the coordinates for you automatically upon export.
Google Earth
MIF
MapInfo Interchange Format
Write areas as curves
Render text
Render marker symbols
Text
Some Drawing Properties
Attributes
Contour Z value (File | Export)
MIFs are a good format choice when transferring data from Surfer to another application. Text, polylines, polygons and points are supported, in addition to attributes, Z values for contour lines, and most drawing properties. Text and marker symbols can be rendered as polygons, if desired.
Other mapping applications
PDF
PDF (Vector) and GeoPDF
Resize embedded images
Image compression
Page size
Text
Images
Some Drawing Properties
This is used for generating high quality PDFs for use in publications and GeoPDFs for use in other programs. Vector PDFs are generally smaller in size than raster PDFs, and the vector objects (text, lines) are higher in quality and do not degrade with increasing zoom. The text can be edited.
Publications
Adobe products
SEG, SP1
SEG-P1 Exchange Format
none
none
This file format contains only discrete point data. Points are exported directly to the file. Polylines and polygons are converted to points and exported to the file. This is typically a format used for storing seismic data, or geophysical shotpoint data.
Geophysical applications
SHP
ESRI Shapefile
Write areas as lines or create a separate file
Write points as lines or create a separate file
Render text
Render marker symbols
Codepage for attribute translation
Attributes
Contour Z value (File | Export)
Contour Z value (Map |Export Contours)
This is a great format for use in other GIS applications. Attributes and Z values are stored in the associated DBF file. Z values can also be stored in the SHP file itself. Note that SHP files do not contain any drawing information (colors, fills, line styles, etc) and can only contain one feature type per file. The only feature types supported in SHP files are points, polylines, and polygons. So you can have one SHP file with all points in it, another for the polylines, and a third for the polygons. Text and marker symbols can be rendered as polygons.
Other mapping applications
SVG
Scalable Vector Graphics
none
Text
Image
Drawing Properties
This is a good format choice when publishing imagery on the web or to another application that supports SVG format. The quality of the original vector objects do not degrade with increasing zoom as it would with a raster image (e.g. PNG, GIF, JPG).
Web pages
Other applications that support SVG
TXT
3D Text
none
Contour Z value (Map | Export Contours)
This is a great way to get the XYZ coordinates of the vertices along the contour lines. The data file consists of XYZ triplets for each point on each polyline.
Data processing
This is a list of the vector file formats available for export from Surfer 12. All the above formats support options for spatial referencing (real world map units and coordinate system information). All formats (apart from SEG-P1) can export points, polylines and polygons. Each format has its own set of export options, additional items supported by that file format, and limitations.
 

Metafiles

There are two additional formats that are actually a blend of raster and vector data. These are the metafile formats, as listed in the table below. A metafile format is an excellent format to choose when inserting maps into reports and presentations. The inserted image looks almost identical to the appearance of the map in Surfer. Raster data (e.g. image maps, 3D surfaces, imported images) are exported in raster format, while lines and text are exported to the file in vector format. After inserting the metafile into another application, there is no degradation in the vector objects when the image is resized, and storing the vector objects in vector format helps keep the file size small. There is no spatial referencing, coordinate system information, attributes, or Z values exported to a metafile format. When you insert a metafile into Word or PowerPoint, or import it back into Surfer, you can break it apart to access the individual items in the file.

File Extension
Name
Format-Specific Options
Comments
Best Formats to Use With
EMF
Windows Enhanced Metafile
resize embedded images
This is an excellent format to choose when inserting maps into Microsoft Word or PowerPoint. The inserted image looks almost identical to the appearance in Surfer. File sizes are small.
Microsoft Word or PowerPoint
WMF
Windows Metafile
resize embedded images
You would only need to use a WMF in place of an EMF if you are inserting the image into an older software program that does not support EMF files.
Older software
The metafile formats are a great choice when inserting maps into Microsoft Word or PowerPoint.
No spatial reference information, Z values, or attributes are exported.
 

Common Scenarios

The tables above contain a lot of information. You can read them in depth, or browse the list below of some common scenarios and the recommended export formats.

Reason for Export
Recommended Export Format
Publication on the web SVG or PNG
Publication in print TIF (atleast 300 dpi) or vector PDF
Insertion into PowerPoint or Word EMF
Use in GIS (and you want attributes) SHP or MIF
Use in GIS (and you want attributes and colors) MIF
Use in GIS/CAD (and you want colors) DXF or MIF
Use in GIS/CAD (and you want Z values of contour lines) DXF or SHP
Use in other Golden Software applications GSI
Use in Google Earth KML
Use as a background image GeoTIFF or GeoPDF
A list of common situations and recommended export formats is presented above.
 

Not all your needs may be met with a single file format. Even in one of the situations above, another format may be more suitable to your needs than the one listed as recommended. For more information, see the list of Supported File Formats on the support website. You are also welcome to email surfersupport@goldensoftware.com with any questions.

Was this article helpful?
0 out of 0 found this helpful
Have more questions? Submit a request

0 Comments

Please sign in to leave a comment.