This file is part of icoformat, a Windows Icon (ICO) File Format plugin for Adobe Photoshop Copyright (C) 2002-3 Toby Thain, toby@telegraphics.com.au This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Windows Icon (ICO) file format plugin for Photoshop --------------------------------------------------- Tested with: - Photoshop 3.0-7.0 on PowerPC Macintosh (OS X and Classic) - Photoshop 4.0 / MacOS 8.0 on 68K Macintosh - Photoshop 5.0 on Windows 98. The plugin adds the ability to Open and Save .ICO files (don't look for it in the Filter or Import/Export menus :) If you use this program and like it, please use http://www.paypal.com to send the author what you think it is worth (US$5 suggested). To install - Copy the "icoformat" folder/package, or an alias to it, into your Photoshop plugins folder. (For 68K Macs, use the "icoformat(68K)" file.) - You will need to quit and relaunch Photoshop if it's already running, before the plugin will be activated. - 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. (Note that the ICO format does not allow images larger than 255 pixels in either dimension, so if your source document is larger than this, ICO will not be available as a format option. Additionally, only Bitmap, Grey Scale, Indexed and RGB modes are supported.) Features - Reads and writes .ICO files of 1,4,8 bits as Indexed mode images, and 16,24,32 bit as RGB mode - If an input file contains multiple icons, a dialog box prompts to select one (this interface may gain a graphic preview later). Note the first icon is numbered ZERO (not one). ICO files created by the plugin contain one icon only. - Note that because Photoshop only allows a file to be opened ONCE, in the case of a file containing multiple icons, only one can be opened at a time (e.g. you can't open icon #0 and also open icon #1, from the same file). - Note ICO images may be no larger than 255 pixels in either dimension. How to make a favicon.ico (favourites/bookmarks/shortcuts/location bar icon) for your website - Make a 16x16 pixel image of your icon in Photoshop (e.g. by rasterising Illustrator artwork) (if needed, use Image Size and/or Canvas Size to get the right pixel dimensions) - Convert it to Indexed colour mode. Use "Palette: Local (Selective)" to reduce the palette to 16 colours (use "Forced: None", no transparency). With a palette of 16 colours, the plugin will choose to write an icon with 4 bits per pixel. While you can also save the icon as a 24-bit or 8-bit image, these formats will be much larger files and slower to download. - If desired, create an alpha channel for the transparency mask, using black where your icon is opaque, and white where it is transparent - Save as "favicon.ico" and copy this file to the root (top level) directory of your web site - Add the following tag somewhere between the
... tags of your home page index file: Also see the following references on the web: * http://www.thesitewizard.com/archive/favicon.shtml * http://www.webdevelopersjournal.com/articles/favicon.html * http://global-positioning.com/favicon/ * http://www.winterdrache.de/freeware/png2ico/favicon.html (for Linux) * http://rock13.com/webhelp/favicon.html * http://www.davesite.com/webstation/html/favicon.shtml * http://www.latext.com/pm/comments/727_0_1_0_C/ (Using a favicon with Safari) ...and many others. About transparency - The ICO format has an inherent 1 bit transparency mask (0 = opaque, 1 = transparent), called the "AND" mask. This appears as an alpha channel (black = 0 = opaque, white = 255 = transparent). If transparency is desired when saving, an alpha channel must exist - unless the image is Indexed colour mode with a "transparent index". - In addition, when opening or saving an RGB mode image in Photoshop 6.0 or later, a 32-bit ICO is created and layer transparency is used as the alpha channel (8-bit transparency) -- the result is an XP icon. In earlier versions of Photoshop, where File Format plugins can't access layer transparency, this 8-bit mask will appear as an additional alpha channel (preceding the ordinary 1-bit AND mask). 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 (256 colours in colour table) * Indexed/Grey Scale mode with >2 colours: 4 bits per pixel (16 colours in colour table) * Bitmap or Indexed/Grey Scale mode with 2 or fewer colours: 1 bit per pixel (2 colours in colour table) Please contact the author with any bug reports, suggestions or comments. The latest version, and source code under the GPL license, is always available from http://www.telegraphics.com.au/