File Types

Appropriate use of file types

Appropriate File Types for communication When we save data to a file we often have

the choice of saving it as a particular type. Choosing the correct type depends on

what we want and what others want to use the file for.

What would we choose and when would we choose it if we want… To use Word to type a document with no pictures, but email it to someone

who does not have office? To create a database file in Excel to email it to someone to use in an Oracle

Database To Create a blueprint drawing of a supermarket to send to an architect who

will need to change specifications of the drawing easily To Create a written document that has security features such as non-

printing, non-cut and paste, non-editing? To send a email of a highly detailed blueprint drawing that can be easily

modified but is very small in memory size?

Bitmap Graphic files

Bitmap graphics are perhaps the most common graphics that we use with computers.

Bitmap graphics include the .jpeg, gif and .tiff extension format.

Why? Because our screens are basically a grid with many little dots.

Bipmap files

The grid has a limited number of pixels. The more pixels the better the resolution when

you look up close. This is what you consider when purchasing a

High Definition vs Standard Definition TV. (Did you know that Foxtel only broadcasts in SD and that there is no True HD television broadcast in Australia. Only when Blue Ray and HD-DV comes out will we truly experience true High Definition)

Vector Graphic files

Vector Graphics are different from Bitmap graphics as the data that makes them up is not information about individual pixels but co-ordinates that are joined together on screen.

Primitives

Like a kids dot-to-dot puzzle, memory would only require 35 points or primitives which the computer program will join up to complete, rather than say 10,000 pixels to make up the image.

Vector Graphics are therefore much smaller in size than bitmap images

Advantages

As the image is made up of co-ordinates that are mathematical in nature, it does not matter how much you enlarge it. No image distortion as with bitmaps will take place

Vector Graphic files

The shoot button has been magnified 8x as a vector image and a bitmap image. Raster images scale poorly, but vector-based images can be scaled indefinitely without degradation.

Text files files

.txt or text files are made in Windows notepad. All word processors allow a user to save a file in notepad format.

•Have you noticed that most help files on cd or dvd are in .txt format?

•This is because even if XP is disabled, you can use dos to open it and read it

Using Word to save document as a text file .txt

Delimited Text files

As every computer in the world can read a .txt file, it makes sense that most applications can also read it.

It makes sense then to choose a delimited text format to transfer data between spreadsheets and databases.

Delimited text files

Delimited data uses specific characters (delimiters) to separate its values. Most database and spreadsheet programs are able to read or save data in a delimited format.

Any character may be used to separate the values, but the most common characters used are the comma, tab, vertical bar

Saving a comma delimited file in Excel for import into a Database

.pdf (portable document format)

Anyone may create applications that read and write PDF files without having to pay royalties to Adobe Systems; Adobe claims that it is an open standard, licensing them on a royalty-free basis for use in developing software that complies with its PDF specification.

Adobe provides a free reader to open .pdf documents. To create documents you need to purchase their software or other software

PDF files are most appropriately used to encode the exact look of a document. While the PDF format can describe very simple one page documents, it may also be used for many pages, complex documents that use a variety of different fonts, graphics, colors, and images.