A favicon (short for "Favorites icon"), also known as a page icon, is an icon associated with a particular website or webpage. A web designer can create such an icon, and many graphical web browsers—such as recent versions of Internet Explorer, Firefox, Mozilla, Opera, Safari, iCab, AOL Explorer, and Konqueror—can then make use of them. Browsers that support favicons may display them in the browser's URL bar, next to the site's name in lists of bookmarks, and next to the page's title in a tabbed document interface. Wikipedia.com |
Figure 1 - Saves image as Desktop icon
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ICO (Windows Icon) file format plugin for Photoshop
The plugin gives Photoshop the ability to directly Open and Save Windows .ICO files. Download latest version here.
The program is fully supported. Please contact the author with any bug reports, suggestions or comments
To install
- Click >here< to download file "favicon.zip."Note: Windows XP version only, Mac users should download latest version here.
- Unzip the files to the Desktop.
- Copy the "ICOFormat.8bi" file, or an alias to it, into the "File Formats" folder
inside your Photoshop Plugins folder (it's probably located in C:\Program Files\Adobe\Adobe Photoshop CS2\Plug-Ins\File Formats).
- Quit and relaunch Photoshop, if it's already running.
To use the plugin
- Use Photoshop's Open command (File menu) to open .ICO files (which will now appear
in the file browser)
- Use Photoshop's Save command to create .ICO files.
Having trouble?
- If you are not sure if the plugin is correctly installed, look for "ICO (Windows Icon)"
under Photoshop's "About Plug-in" menu (on Windows, look under "Help"; on OS X, under "Photoshop").
If it is not listed:
- check you have downloaded the correct version (Windows/Mac)
- try moving the plugin file to the "File Formats" subdirectory of Photoshop's "Plugins" folder.
- have you quit and re-launched Photoshop?
- The plugin is not a Filter or Import/Export plugin, so don't look for it there.
It appears as a format option when Opening or Saving (eligible images).
- The ICO format does not allow images more than 255 (32 x 32 is typical) pixels high or wide,
so if your image is larger than this, ICO will not be available as a format option. To save as needed go to Image>Image Size and resize to 32 pixels x 32 pixels.
- Only Bitmap, Grey Scale, Indexed and RGB mode images, no more than 8 bits per channel,
can be saved as ICO.
How to add a "Favorites" icon (favicon, favicon.ico) to your web site
- Create the file named "favicon.ico" with your desired graphic, and put it at the root level
of your web site.
- Put a tag as follows between <HEAD>...</HEAD> of your top-level HTML page (home page):
<link rel="icon" href="http://arapaho.nsuok.edu/~userid/favicon.ico">
<link rel="shortcut icon" href="http://arapaho.nsuok.edu/~userid/favicon.ico">
Sample Code
Note: 'userid' is YOUR userid e.g.,
<link rel="icon" href="http://arapaho.nsuok.edu/~stretch/favicon.ico">
<link rel="shortcut icon" href="http://arapaho.nsuok.edu/~stretch/favicon.ico"
Also see the following references on the web:
...and many others.
About transparency
The ICO format has an inherent 1 bit transparency mask (0 = opaque, 1 = transparent), called the AND bitmap.
- When reading or saving an RGB mode image in Photoshop 6.0 or later, layer transparency is used for the mask
- If the image is Indexed mode, and uses a "transparent index", this will be used to set the icon mask
- In other cases, the ICO mask is treated as an alpha channel (black = 0 = opaque, white = 255 = transparent)
Saving indexed mode images
To ensure output files are as compact as possible, the smallest pixel depth is chosen
sufficient to represent the colours used by the icon:
- RGB mode: no colour table
- Indexed/Grey Scale mode with >16 colours: 8 bits per pixel (up to 256 colours in colour table)
- Indexed/Grey Scale mode with >2 colours: 4 bits per pixel (up to 16 colours in colour table)
- Bitmap or Indexed/Grey Scale mode with 2 or fewer colours: 1 bit per pixel (up to 2 colours in colour table)
A note on file sizes (Mac only)
Do not be alarmed if the Mac Finder shows an unexpectedly large file size for ICO files saved out of Photoshop.
The ICO itself is stored in the data fork and is as small as possible (see above).
The Finder's size calculation is increased by Photoshop's prolific "metadata" in the resource fork,
and does not truly reflect the size of the ICO data. (This is stored for all files saved out of Photoshop,
regardless of format, and whether image thumbnails and previews are enabled in Preferences.)
Finder's "K" size is also affected by the volume's minimum allocation size (often 4 or 8K depending on partition size).
On upload to a web site, the data fork alone is copied and the resource fork is stripped, and so this extra data
(and Finder's padded figure) has no effect or relevance whatsoever. The "true" logical size of the ICO file
can be confirmed in OS X's Terminal with ls -l in the icon's directory (or files -x br in MPW Shell).
The plugin can create 32-bit icons with 8-bit alpha transparency. This will occur in two cases:
- in Photoshop 6.0 or later, saving a layered RGB image (i.e. not flattened)
- in any version of Photoshop, saving a flat RGB image with 2 or more alpha channels.
In the first case, the layer transparency will be used as the ICO alpha.
The 1-bit "AND mask" is taken from the first alpha channel, or if there is no available alpha channel,
is derived from layer transparency.
In the second case, the first alpha channel is used to create the 1-bit "AND mask",
and the second alpha channel becomes the 8-bit ICO alpha.
In both cases, the colour data is set to zero (black) where the icon is transparent.
This should produce the desired result (complete transparency over the background). |
