File format

1. File Format

2. Lesson Goals
Must know file formats used for images, audio and video
Should understand pre-production and final product file
formats
Could be able to describe properties and limitations of file
formats

3. Viewing Digital Media
What devices can we use to view digital media files?

4. 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:
Know image, audio and video files
Be able to describe file formats

5. 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 files
Be able to describe file formats

6. Image File Formats
Watch the video and identify the good and bad features of five image file types:
GIF PNG EPS

7. File Type Good Points Bad Points
GIF
PNG
EPS
Zooming in is good quality
Millions of colours
Compresses well
Not good for sharp edges
Not great for text
Some colour detail is lost when compressed
Features millions colours
No colours are lost
No or little compression
Not compatiable with all applications
Large file sizes
Compresses well
Very small file size
Only has 256 colours
Doesn't show all colours
Millions of colours
Compresess well
Sharp edges
Not compatiable with all applications
Can only use in a few particular places
Doesn't lose colour or detail
Scalable to any size
Does not lose any colour quality
Can only open in certain software

8. 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:
Know image, audio and video files
Be able to describe file formats
JPEG GIF

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

10. Compression
Digital media files can be either uncompressed or compressed:
Know image, audio and video files
Be able to describe file formats
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.

11. Compression
There are two main methods for compressing files:
Know image, audio and video files
Be able to describe file formats
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.

12. 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 files
Be able to describe file formats
File Properties Limitations Compression
The following website may help:
www.file-extensions.org

13. Playing Audio and Video
Describe the different devices that could be used…

14. Video

15. File Formats
Because there are so many different audio and video playback devices
and different ways to distribute files various file formats are required.
Some people will sacrifice quality for smaller file sizes while others may
required top quality files regardless of file size.
Audio file formats can vary in:
File Size
Quality
DRM
Compression
Know image, audio and video files
Be able to describe file formats
 Video file formats can vary in:
 File Size
 Quality
 Resolution
 Compression

16. Audio Files
When comparing the file size of a 3 minute music track saved in different
file formats you can clearly see the effect of audio compression:
Know image, audio and video files
Be able to describe file formats
WAV 30.4mb
WMA 15.6mb
MP3 4.2MB
MP3 1.4mb
192kbps
64kbps

17. Video Files
Different file formats render videos in different ways showing a variation:
The OGG file tends to look a little bit dark compared to an MP4 but has
the benefit of being a much smaller file size.
Know image, audio and video files
Be able to describe file formats

18. File Formats
When researching file formats remember the following points:
Compression may have good and bad consequences:
Properties – Small file sizes would upload quickly.
Limitations – File would be a lower quality.
Know image, audio and video files
Be able to describe file formats
More
Compression
Lower
Quality Files
Smaller File
Sizes
Quicker
Upload
Speed

19. File Formats
File formats you could research for your work include:
Know image, audio and video files
Be able to describe file formats
Audio Video
CompressedUncompresse
d
avi
wmv mov
mpg mp4
swf
flv
aiff wav
mp3 wma
aacogg
flac