File FormatsLesson 7

Lesson Goals

Know file formats used for images, audio and video

Understand the use of file compression techniques

Be able to describe properties and limitations of file formats

#limitation#property

Viewing Digital MediaWhat devices can we use to view digital media files?

Digital Media

Because there are so many different platforms which we can view images, video and audio we need different file formats depending on the device:

#limitation#property

Know image, audio and video filesBe able to describe file formats

Digital Media

Digital media devices are required to be able to play back the following:

There are various different types of audio, image and video file and each one is used for a specific reason or type of job.

These different files will also vary in their quality, file size and the way that the file is compressed.

Know image, audio and video filesBe able to describe file formats

#limitation#property

Image File FormatsWatch the video and identify the good and bad features of five image file types:

JPG TIFF GIF PNG EPS

File Type Good Points Bad Points

JPG

TIFF

GIF

PNG

EPS

Image Formats

Different image file formats are used depending on the way in which you want to use or display the image files but the quality varies greatly:

#limitation#property

Know image, audio and video filesBe able to describe file formats

JPEG GIF

What is compression?Think of what the keyword may actually stand for…

Compression

Digital media files can be either uncompressed or compressed:

Know image, audio and video filesBe able to describe file formats

#limitation#property

Uncompressed

Compressed

This is the original file which is at the best quality it could ever be. These files are usually used just for storage because they have massive file sizes.

This is a file that has been made smaller to store on things like portable devices. They are poorer quality than uncompressed files but have a much smaller file size.

Compression

There are two main methods for compressing files:

Know image, audio and video filesBe able to describe file formats

#limitation#property

Lossless

Lossy

This technique uses a formula which doesn’t lose any of the original data so the quality of lossless compression files is good.

This technique gets rid of any data it thinks is unnecessary. File sizes are much smaller but the quality is poor compared to lossless.

Your Task

Create a table showing properties and limitations of each image file: Big or small file size? Common file or not? Where is it used?

State if the file is compressed or uncompressed.

Know image, audio and video filesBe able to describe file formats

File Properties Limitations Compression

#limitation#property

Key Words

File Format

Properties

Limitations

Compression

The standard way that a digital media file is stored on a computer

Features of the file format such as the size and quality of the file

Something that is a restriction on what you are doing or want to do

Making a file smaller for broadcast on different platforms