Loading Indicator GIF

LOADING ... Here is the some samples of GIF images that can be used as page loading indicator. The GIF images were generated based on the color schemes of this blog, so it may not be suitable for other blog with different color schemes.

If you want to use it for your blog or web page, you can download directly from the original source here. At this website, you can adjust the color schemes to your liking and then generate the GIF images.

For more information on how to add page loading indicator to your blog, please refer to this post.


3D Rotation


Arrows


Bar


Bar 2


Bar 3


Bar Circle


Big Circle Ball


Big Flower


Big Roller


Big Snake


Bouncing Ball


Circle Ball


Circle Thickbox


Circling Ball


Clock


Drip Circle


Expanding Circle


Flower


Hypnotize


Indicator


Indicator Big


Indicator Big 2


Indicator Lite


Kit


Pik


Pk


Radar


Refresh


Roller


Smallwait


Snake


Squares


Squares Circle


Wheel


Wheel Throbber



External References

• Ajaxload
  

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PNG Transparency in Web Design

LOADING ... Portable Network Graphics (PNG) is a bitmapped image format that employs lossless data compression. PNG is pronounced "ping", but can be spoken "P-N-G". PNG was created to improve upon and replace the GIF format, as an image-file format not requiring a patent license.

Besides being a freely available format, PNG offers several practical advantages over GIF for the web designer, as follows:

• Greater compression: For most images, PNG achieves a smaller file size than GIF.
  
• Greater color depths: PNG offers truecolor up to 48 bits, whereas GIF allows only 256-color palettes.
  
• Alpha-channel transparency: Whereas GIF offers only binary transparency, PNG allows for virtually unlimited transparency effects by enabling an alpha channel for transparency.
  

Alpha Channels
Also known as a mask channel, an alpha channel is simply a way to create the appearance of partial transparency. Whereas GIF supports simple binary transparency--any given pixel can be either fully transparent or fully opaque--PNG allows up to 254 levels of partial transparency in between.

All three PNG image types--truecolor, grayscale and palette--can have alpha information, but it's most commonly used with truecolor images. Instead of storing three bytes for every pixel (red, green and blue), now four are stored: red, green, blue and alpha, or RGBA.

The alpha channel is the opacity channel. If a pixel has a value of 0% in its alpha channel, it is fully transparent (and, thus, invisible), whereas a value of 100% in the alpha channel gives a fully opaque pixel (traditional digital images). Values between 0% and 100% make it possible for pixels to show through a background like a glass (translucency) or retain their anti-aliasing no matter the background, effects not possible with simple binary (zero/full) transparency. It allows easy image compositing and, in HTML pages, inclusion of images with no background (especially if page background is multi-colour).

For example, in this website, I used PNG images with alpha-channel transparency for the header image and the three column box, so that it can rest on top of the “cloud” background while still showing rounded-corners and drop shadows.


Which browsers support PNG?
Almost all modern browsers fully support PNG images, including the alpha-channel transparency, such as Safari (all versions), Firefox (all versions), Opera (version 6 and higher), Netscape (version 6 and higher), and Mozilla (all versions).

However, Internet Explorer does not fully support PNG images, not until version 7. The previous versions (from 5.5 up to 6) do not support alpha-channel transparency, but it can still show the non-transparent part. It is still possible to show the transparent part, but you need to use a non-standard filter called AlphaImageLoader.


AlphaImageLoader
This is Internet Explorer proprietary filter, designed as workaround for displaying alpha-channel transparency in PNG images. They’re used in CSS, but they’re not part of any official CSS specification. In other words, they’re not a web standard.

No other browsers support AlphaImageLoader filter, not that they need it, so the CSS code for this filter must be hidden from other browser by using Conditional Comments.


AlphaImageLoader for Background Image
The code must be placed inside the head element, between

<head>

 and

</head>

.

<!-- This code for all browsers -->
<style type='text/css'>
.main {
  background:url("http://photobucket.com/image.png") no-repeat;
  }
</style>
 
<!-- This code for IE 5.5 – 6 AlphaImageLoader -->
<!--[if (gte IE 5.5)&(lt IE 7)]>
<style type='text/css'>
.main {
  background: transparent none;
  filter:progid:DXImageTransform.Microsoft.AlphaImageLoader( enabled=true, sizingMethod=scale, src='http://photobucket.com/image.png');
  }
</style>
<![endif]-->

Then you can put below code inside body element, between

<body>

 and

</body>

.

<div class='main'>Hello</div>

AlphaImageLoader for Normal Image
There are several ways to do this, but the one I recommend is to use JavaScript to check your browser type and version, then use the filter when necessary. This way, you don’t have to add a bunch of codes for each PNG images.

HTML codes for the images:

• For PNG:
  

  <img width="10" height="10" src="http://photobucket.com/image.png" onload="fixPNG(this)" />

  
  
• For GIF:
  

  <img width="10" height="10" src="http://photobucket.com/image.gif" />

  
  
• For JPG:
  

  <img width="10" height="10" src="http://photobucket.com/image.jpg" />

  
  

Example:


The JavaScript code below must be placed inside the head element, between

<head>

 and

</head>

.

<script type='text/javascript'>
var arVersion = navigator.appVersion.split("MSIE")
var version = parseFloat(arVersion[1])

function fixPNG(myImage) {
  if ((version >= 5.5) && (version < 7) && (document.body.filters)) {
    var imgID = (myImage.id) ? "id='" + myImage.id + "' " : ""
    var imgClass = (myImage.className) ? "class='" + myImage.className + "' " : ""
    var imgTitle = (myImage.title) ? "title='" + myImage.title  + "' " : "title='" + myImage.alt + "' "
    var imgStyle = "display:inline-block;" + myImage.style.cssText
    var strNewHTML = "<span " + imgID + imgClass + imgTitle + " style=\"" + "width:" + myImage.width + "px; height:" + myImage.height + "px;" + imgStyle + ";" + "filter:progid:DXImageTransform.Microsoft.AlphaImageLoader" + "(src=\'" + myImage.src + "\', sizingMethod='scale');\"></span>"
    myImage.outerHTML = strNewHTML   
    } //end if
  } //end function
</script>

This script was created by Bob Osola.


External References

• Portable Network Graphics – Wikipedia
  
• Intro to PNG Features
  
• PNG in Internet Explorer
  

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Conditional Comments

LOADING ...

Conditional Comments allow web developers to show or hide HTML code based on the version of the Internet Explorer browser used by viewers. Conditional Comments are supported by IE only (version 5 or greater), but can still be useful for other browsers as it can be used to indicate separate HTML codes to be processed, one set for IE and the other for non-IE.

This is an important feature as different browser types or versions process the same code in a different way, hence give different results. So, web developers may need to provide different codes for each browser types or version in order achieve the same or similar results. For example, IE version 6 or less does not support PNG image display by using the default IMG tag. Instead, it requires additional tag to make use of filter AlphaImageLoader. See more in PNG Transparency in Web Design article.


Code for IE

<!--[if IE]>
  Insert HTML code here. 
  This code can be processed only by IE (version 5+).
<![endif]-->

Code for non-IE

<![if !IE]>
  Insert HTML code here. 
  IE 5+ will not process this code. 
  Non-IE will process this code.
<![endif]>

This is recommended by Microsoft for when the content should be exposed to non-IE browsers. Microsoft acknowledges this method is not standardized markup for comments, intending these tags to be overlooked by other browsers and expose the content in the middle. Some web developers use an alternative technique for non-IE conditional comments in order to only use standardize markup.

<!--[if !IE]>-->
  Insert HTML code here. 
  IE 5+ will not process this code. 
  Non-IE will process this code.
<!--

IE Version
Conditional Comments can be used to assign specific codes for specific IE version. Example:

<!--[if IE 7]>
  You are using IE 7!
<![endif]--> 

A combination of feature, operator, and/or value can be used to form a conditional expression, as shown in the following table.

Item	Example	Comment
IE	[if IE]	The only currently supported feature is the string "IE", corresponding to Internet Explorer.
value	[if IE 7]	An integer or floating point numeral corresponding to the version of the browser. Returns a Boolean value of true if the version number matches the browser version.
!	[if !IE]	The NOT operator. This is placed immediately in front of the feature, operator, or expression to reverse the Boolean meaning of the expression.
lt	[if lt IE 5.5]	The less-than operator. Returns true if the first argument is less than the second argument.
lte	[if lte IE 6]	The less-than or equal operator. Returns true if the first argument is less than or equal to the second argument.
gt	[if gt IE 5]	The greater-than operator. Returns true if the first argument is greater than the second argument.
gte	[if gte IE 7	The greater-than or equal operator. Returns true if the first argument is greater than or equal to the second argument.
( )	[if (IE 7)]	Subexpression operators. Used in conjunction with boolean operators to create more complex expressions.
&	[if (gt IE 5)&(lt IE 7)]	The AND operator. Returns true if all subexpressions evaluate to true.
|	[if (IE 6)|(IE 7)]	The OR operator. Returns true if any of the subexpressions evaluates to true.
true	[if true]	Always evaluates to true.
false	[if false]	Always evaluates to false.

External Reference

• About Conditional Comments
  
• CSS Filters - Wikipedia
  
• AlphaImageLoader Filter
  

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Favicon

LOADING ... A favicon (short for 'favourites icon'), also known as a website icon, a page icon or an URL icon, is an icon associated with a particular website or webpage. A web designer can create such an icon, and many recent web browsers can then make use of them. Browsers that support favicon 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.




Location of favicon
The original means of defining a favicon was by placing a file called favicon.ico in the root directory of a web server. This would then automatically be used in the browser’s favourites (bookmarks) display. Later, however, a more flexible system was created, using HTML to indicate the location of an icon for any given page. This is achieved by adding two link elements in the section of the document as detailed below.

<link rel="shortcut icon" href="http://x.com/favicon.ico"
      type="image/x-icon">

<link rel="icon" href="http://x.com/favicon.ico"
      type="image/x-icon">

Note:

• The link elements must be inside the head element, between

  <head>

   and

  </head>

  .
  
• For XHTML, the link element must be terminated by

  />

   instead of

  >

  .
  

Recently, some browsers such as Firefox and Opera also support other image format, such as GIF and PNG, which allows animated/transparent images (GIF) and partially transparent images (PNG). For GIF/PNG files, use the following type:

• GIF files

  type=”image/gif”

  
  
• PNG files

  type=”image/png”

  
  

Most photo sharing website such as Photobucket and Flickr currently does not support ICO files though, so unlike the regular images (JPG, GIF, or PNG files), favicon ICO files should be stored elsewhere. On contrary, most web hosting services, such as Geocities, allows you to store ICO files. So, look for web hosting services for a place to store the favicon ICO files.


Resolution and Color Depth

• ICO: include multiple resolutions (the most commonly used being 16×16 and 32×32) and bit-depths (most common being 4-bit 16 colors, 8-bit 256 colors, 24-bit 16 million colors, and 32-bit 16 million colors with 8-bit alpha channel).
  
• GIF: use 16×16 resolution in 256 colors.
  
• PNG: use 16×16 resolution in either 256 colors or 24-bit.

As most recent browsers support ICO files, but some of them do not support GIF/PNG files, it is recommended to use ICO files whenever possible.


Create favicon
Usually favicon.ico file contains 2 icons, 16x16 and 32x32 resolution. Some graphics editor applications support ICO files, such as GIMP. Some others may require additional plugins in order to support ICO files, for example, Photoshop requires a plugin from Telegraphics. The same website also provides tool to combine multiple ICO files, e.g. combine ICO file with 16x16 and 32x32 resolution.

First begin with 32x32 resolution, as it is more difficult to work with the smaller 16x16 resolution. With your preferred graphics editor, start your project with a canvas set at 32x32. It is possible to start with a bigger canvas, such as 64x64, and scale it down once finished. However scaling down an image usually will reduce its quality.

Once familiar with the 32x32, you may proceed with the 16x16.


Inspiration
Some nice collection of favicon can be found at Smashing Magazine. [-] Hide Full Post

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