All posts tagged ‘Multimedia’

File Under: Glossary

MIME

Defined in 1992 by the Internet Engineering Task Force (IETF), multipurpose internet mail extensions, or MIME types, are a specification for formatting non-ASCII messages so that they can be sent over the internet.

When a browser comes across a file in an HTML document with a MIME extension (like .gif), the browser knows to display that file as an image. Many email clients also support MIME, enabling them to send and receive embedded media via the internet mail system.

File Under: Glossary

Pixel


The cell is nature’s building block, and the pixel is the web designer’s. Pixel is one of those half-baked half-acronyms:PICture ELement. It refers to how monitors divide the display screen into thousands or millions of individual dots. A pixel is one of those dots. An 8-bit color monitor can display 256 pixels, while a 24-bit color monitor can display more than 16 million. If you design a web graphic on a 24-bit monitor, there’s an excellent chance that many of your 16 million pixels won’t be seen by visitors to your site. Since the agreed-upon lowest common denominator palette for the web has 216 colors, you should design your graphics using 8-bit color. (see Bit Depth)

File Under: Glossary

Bitmap

A bitmap is a mapped array of pixels that can be saved as a file.

Both JPEG and GIF are bitmap graphic formats. Currently, the only other way to store an image is as a vector graphic. You can’t easily scale bitmap images, but you can control every single pixel and thus achieve many effects impossible in vector graphics. Conversely, vector formats offer advantages of scalability and lower bandwidth requirements. When you compress a bitmapped image, you suck out some of the visual information.

To bypass this, the portable network graphics format (or PNG, pronounced “ping”) was designed to store a single bitmap image for transmittal over computer networks without losing this data.