You're likely familiar with popular image formats such as .gif, jpeg, and
.bmp. Many different image file extensions exist. However, in order for a
Web browser or email program to know which program to use to open these
files, they need to know what type of information the file contains. That's
where MIME Image comes in. MIME types were original created to solve
problems with email programs and attachments by defining what the content
type of the attached file was. For example, if someone emailed you a
picture, the MIME Image type would tell the email program that it was an
image file. Thus, the email program would open the image file in a
compatible program. Had the MIME type been set to Text or Audio, then either
a text editor or audio player would be launched.
Some of the more common MIME Image types are:
Opening a MIME Image file requires an image viewing application
compatible with the MIME type. Depending on where the file comes from, you
may need to add a plug-in to your Web browser or open an appropriate program
on your computer. For example, if you are encountering a MIME Image error
when browsing the Internet, then it's likely that your Web browser does not
understand that a given file is an image file. On the other hand, if you
received a file as an email attachment, then the email program doesn't know
which program to use to open it.
Your Web browser gets information about known MIME types using either a process known as FindMimeFromDataMethod or a MIME handler which looks at your Windows registry in search of compatible programs. In most cases, you won't need to do anything to open MIME Image files in your browser.
If you receive file with the MIME Image type but your computer doesn't know which program to use, you can manually open the file by launching an image editor or viewer compatible with the file's extension and then opening the file. For example, if you have Windows, your computer comes preinstalled with Paint which is compatible with a variety of image files including .bmp, .jpeg, .gif, .tiff, .png, and .ico. Go to Start > All Programs > Accessories > Paint and then open the file.
In addition to the built-in Paint program, many other programs exist for
opening MIME Image files including:
Windows Picture and Fax Viewer If you have Windows XP, Windows Picture and Fax Viewer is already on your computer.
Windows Live Photo Gallery Part of the free Windows Live Essentials suite, this tool can open a variety of image files including .jpeg, .tiff, and .wmphoto.
Irfanview This free photo editing program is extremely popular and capable of working with many image file types including most of the common ones and .psd, .eps, and .ico.
Picasa Offered for free from Google, Picasa supports numerous image file types including .jpeg, .tif, .tiff, .bmp, .gif, .psd, .png, .tga, and some RAW formats (.dng, .crw, .raw, .raf, .3fr., .dcr, ..kdc, .dng, .mrw, .nef, .nrw, .orf, .rw2, .pef, .x3f, .srf, and .sr2.)
Oftentimes, file associations become broken. While your image files may
have previously opened in Windows Live Photo Gallery, if the file
association is broken, your computer may no longer know how to handle the
image file. When this happens, you can reset the file association by using
Windows Explorer to navigate to the file, right-clicking the image file,
choosing Open With > Choose Default Program, and browsing to the appropriate
program. To make it the default, place a checkmark in the box that says,
"Always use the selected program to open this type of file."
MIME Type Detection in Internet Explorer This page explains how Internet Explorer 4.0 and above automatically detects MIME types using the FindMimeFromDataMethod. This process automatically detects known MIME types and launches the appropriate object servers or applications to display the content.
Handling MIME Types In Internet Explorer In Windows XP and later, Internet Explorer references the Windows registry to learn more about the MIME type. Thus, a MIME handler is used. This article discusses how MIME types are handled as well as how to update the MIME handler to handle specific file types.