Transparency in ArcGIS

(or lack there-of...)


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ArcGIS makes an attempt at being able to make and use symbols and/or layers and/or data frames that are transparent (or semi-transparent). It doesn't always work and even if it looks like you want in ArcMap it may or may not print or export the way you want... In theory, you should be able to set one color of a file (typically white or black) as transparent so that only the other colors are shown. Most commonly, this would be used for a image file where the background would be set to transparent, leaving only the foreground / symbol visiable. Be careful, however, for images that use the same color for the background as for other portions of the image itself. For example, the file on the left below is a .jpg file, note that it has a white background but also makes use of white in the shield itself. The file on the right is a .png file with the white color set to be transparent. This "removes" the background but note that it Also removes the white portion of the shield itself - which may be undesireable...


image as jpg with white background image as png with transparent background


(note: if you wanted to have just the background be transparent and not the white portion of the shield, you could open the image in Photoshop, swap the background for some other color (pink or something) and then set that color to be transparent in the save process (see notes below), preserving the solid fill for the entire shield.




GRAPHICS FILES (Image files)

There are many different file types for pictures. Some of the more common are .jpg, .tif, .gif, .bmp and .png. Some of these types of files (i.e., png, bmp, gif files) can have a transparent background (when used in ArcMap). Some types of files (i.e., jpg, tif) cannot have transparent backgrounds (at least in ArcMap). If you have a jpg file (or a .gif, etc. that doesn't have transparency specified) you can convert the file to a .png file and set a single color as transparent (see notes below).


Part of the frustration is that there are multiple different ways to include images in a map... some of which allow transparency and some of which don't. You can use images/graphic files as Picture symbols for a layer or as a Picture symbol for a graphic marker (point). Or you could use Add Data and bring the graphic is as a layer. Or you could use the Insert menu (from either Data or Layour view) to insert a picture...




Insert Menu

From what I can tell, if you use the Insert / Picture menu (from either Data or Layout view) the image will not be transparent. Even if it is transparent in other programs (or other uses within ArcMap) the background will be white. This is annoying, but fortunately there are some work-around options.



Pictures used as Symbols

You can also use a graphic file as a Picture Symbol for either a points file (a data layer in ArcMap) or for individual graphics markers (points added manually using the Add Marker tool from the Draw toolbar). These can be resized as needed, and can make use of a transparent background. To do this:

  • Open the Properties (for either a points layer or a graphic marker)
  • Open the Symbology (or Symbol) tab
  • Click on the symbol (or Change Symbol)
  • Click on Edit Symbol... (from the Symbol Selector dialog box)
  • For Type: choose Picture Marker Symbol (from the drop down list in the Symbol Property Editor dialog box)
  • Browse to the location of the file you wish to use and select it
  • Click Open, OK, OK, OK...

IF your file has a transparent background already set (and is the right type of file, like a .png file) then this should show up with the transparency as desired. If the file had a simple, solid background (white, black, etc) and is the right type of file (again, .png or .bmp or .gif) you may be able to set the background to transparent in ArcMap (note this only works for certain types of files):

  • Once again open the Symbol Property Editor (Symbology / Edit Symbol...)
  • For the Transparent Color, choose the color you wish to be transparent
  • Note that this has to be a perfect match for it to work. For example, in the file above on the left, the background is slightly off-white - thus choosing pure white for the Transparent Color won't work, instead you would need to specify an RGB of 247-247-247

Note that if you are using the image file as the Picture Symbol for a layer (as opposed to for a single marker symbol) you can also set the transparency for the entire layer (from the Display tab of the Layer Properties). This will set the entire picure to transparent or semi-transparent (regardless of wheither or not the picture has a transparent background).



Data Frames

Data Frames can be set to use a transparent background. These look especially nice for global maps using oval or circular projections. It doesn't always work, depending upon the projection, the data layers, etc. Often the background of the map will appear transparent in ArcMap, but when printed or exported there will be a white box instead of a transparent box... this is (somehow) a issue between ArcMap and the Microsoft print engine... and apparently not easy to solve, as it has been an issue for year. In most cases, exporting the map as a high-resolution (300 dpi or more) .jpg file and then printing that will work...



Legends, Text boxes...

Legends and text boxes are graphic elements in ArcMap. As such they cannot be set to be semi-transparent. For a legend (or text box) the best workaround I've found is to create a box (or whatever shape you want) as a shapefile (i.e., a data layer). Locate your box where you want it to be for the legend. As with any data layer you can set the transparency to whatever % you like. This creates a semi-transparent box. On top of that box you can create a simple text box or your legend (with no background) that will be on top of the box. The text/legend itself won't be semi-transparent, but the box will be. Not unlike this:

semi transparent legend box



North Arrows, Scalebars, Text...

North arrows, scalebars and text are graphic elements in ArcMap. As such they cannot be set to be semi-transparent.




Creating a .png file with a Transparent Background (using Irfan View)

If you have a .jpg (or other file type) that does not have a transparent background you can convert it to a .png file (which can have a transparent background such that ArcMap will recogognize it) using Irfan View (or some other graphics editor program, such as Photoshop, etc.


  • Open the file in Irfan View (or a similar graphics program)
  • From the File menu choose Save As
    • Make sure the location to save the file to is where you want it
  • For the Save As Type choose PNG - Portable Network Graphics
  • In the PNG/PNM/ICO Save Options dialog box:
    • Check the box for Save Transparent Color
    • Optionally choose a lower Compression level for better display (it may not matter)
  • Click Save
  • In the Choose Transparent Color dialog box
    • Click once on image in the background area of the image (somewhere that has the color that you want to become transparent)
  • Now try bringing this .png file into ArcMap as a Picture Symbol
    • The background should be transparent


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