Before analyzing sIFR, let’s quickly understand what sIFR is and how it works. sIFR stands for scalable Inman Flash Replacement, which is a technology for accurately publishing custom layouts on the web. This technique is implemented by replacing some text with Flash-rendered text in a specified element when the page is downloaded. It's important to understand that this element is not completely replaced by Flash, the text is still within the element, and the element can still be styled or positioned as usual.
Some facts about sIFR: not meant for debate
sIFR does not require changes to the (X)HTML code, all work is done by Javascript, Flash and CSS;
If the user does not have Flash installed or does not support Javascript, the (X)HTML text will be displayed after being styled by CSS.
sIFR is scalable and can be changed to a user-set default font size at render time.
sIFR is compatible with all screen readers and no issues have been reported so far.
sIFR text can be selected with the mouse, although when all text is selected, the selected state does not appear to be precise.
sIFR does not affect the positioning and evaluation of search engines and does not hide the true text content.
The conclusion should be that sIFR is a usable, discreet technology that designers and developers should give serious consideration to when using it.
When to use sIFR
As with all web technologies, it's important to understand the best way to use sIFR, and to know when it's most appropriate to use it. This refers to choosing the right tool for the job, especially when sIFR pops up as a tool out of the toolbox for us to use.
Case: A large sports news site decided to design all titles in the company's unique font. News stories (including their headlines) are published in different places by different people around the world through some content management software. They can't hire someone to sit in front of Photoshop and create a headline image every time the editors want to add a news story.
In this case, sIFR is an absolutely simple, usable and extensible tool. Some news sites solve this problem by busily creating images through PHP, or using some other server-side means. This method can be a great time saver, but when compared to sIFR, you will see that it has many disadvantages:
Images cannot be scaled to the user's default font size.
Although the image is cached on the server, there is still a performance issue when generating the image.
Each image must be downloaded separately, resulting in server and bandwidth consumption.
With sIFR, only one Flash (.swf) file and one Javascript (.js) file are downloaded, allowing all titles on the site to be rendered as the company's fonts.
This example is not groundless. This is a real case, in 2001, in order to redesign ESPN.com, Mike Davidson developed the original Flash replacement technology. Since then, with the addition of Shaun Inman and others, this has grown into the complete and fluid technology we have today, and is likely to have a major impact on web layout technology in 2005.
Use sIFR on links
The latest version of sIFR allows link text to be replaced. Although this is an exciting development, it is not suitable for use in this situation. This is due to the following accessibility issues:
Browser right-click functionality (context menu) is not supported
Does not support apple's option key
No status bar information
Although these issues may seem trivial, many people find the lack of these features frustrating. Without the status bar information, you have no clue as to where you want to visit next; with the popularity of browsers such as Firefox and Opera, right-click context menus are becoming an increasingly useful tool. Although sIFR provides a basic right-click on the link, the browser's context menu is not accessible.
Of course, this is a limitation of Flash rather than a limitation of sIFR itself. These problems look like they can be overcome in the future. For example, the status bar can be controlled via Javascript, so adding the ability to display link targets shouldn't be difficult. However, until Flash allows full browser context menus on links, I believe sIFR won't be able to fully handle this type of text.
anti-aliasing
Most of the benefits of sIFR focus on the ability to customize fonts. An important consideration is that Flash text can be anti-aliased. Web developers often forget this, in part because so much work is done with Mac OS X, whose Quartz fonts can produce smooth edges. However, Windows users (despite having an option to smooth font edges somewhere in the Display menu) do not appear to be able to have anti-aliasing enabled. These users, like those who come pre-installed with Windows XP or Mac OS X, have display anti-aliasing. Capacity of the title is an important consideration.
fine adjustment
One issue I've heard mentioned several times is that sIFR doesn't allow you to control text in the same way you can control an image. Indeed. With images created in Photoshop or Fireworks, you can precisely control kerning, stretching, anti-aliasing, or other features such as very accurate drop shadows. The image editor is a true WYSIWYG (What You See Is What You Get) medium. sIFR rendered to Flash is not.
If this level of control is required, then an image is still the best way to publish this type of text, and sIFR is not the right tool in these cases. However, if you are purely publishing a custom font, sIFR is more suitable than creating an image.
Download speed
The speed of shading of replacement text is an important consideration when using sIFR. Although the speed has been greatly improved since earlier versions, if there are many instances of sIFR on the screen at the same time, there are still Noticeable delay. (For example, each page has a title, or each transfer has a title.) This example may best illustrate why moderate use of sIFR is the ideal way to use this technology today.
This is the most frustrating drawback of using Flash replacement technology. Ever since the first sIFR was implemented, the temptation has been to replace too many elements on a page. In order to achieve them, download speeds must be greatly improved; although a good server can help you, what really consumes time is running those bulky Javascripts.
Summarize
sIFR does not compete with image replacement technology; it is a unique tool for different tasks. It is best used for text that is displayed in the browser's default font size and cannot be replaced with a custom image.
The ideal use case for sIFR is when you want to display a custom font or anti-aliased title with just a single image. This is used very frequently on the web, and sIFR is a better choice in these cases. It scales to the user's default font size, can be selected, and can be used on thousands of pages without downloading just one or two files.