This document discusses various methods for compressing animation files, including reducing aspect ratio, frame rate, and using codecs. It describes lossless compression, which preserves quality, and lossy compression, which achieves higher compression ratios but can reduce quality. Common compression formats discussed include MPEG, QuickTime, SWF, AVI, and GIF.

1. Animation File Format
CHAPTER 4

2. Concept of Compression
SL
4.2
 There are several methods can be implemented to
compress animation, such as;
 Reducing aspect ratio; eg. from 640 x 480 to 320 x 240.
 Reducing frame rate; eg. from 30 fps to 15 fps.

3. CODEC
SL
4.3
 Compression/Decompression algorithm
(CODEC) has been developed to reduce the file size
and enables animation to be stored in one storage
media, such as CD or hard disk.
 A codec is software that is used to compress or
decompress a digital media file, such as a song or
video.

4. CODEC
SL
4.4
 In general, CODEC runs compression and
decompression of data, where data will be
compressed into smaller packets so that it can be
stored and distributed easily.
 Compression replaces pixels with mathematical instructions,
resulting much smaller size of file.
 Decompression decodes the mathematical instruction back
into pixels.

5. Data Compression
SL
4.5
 Example of data compression software:
 7 ZIP, Advance Comp, Bzip2, File Roller, Gzip, P7zip,
PNGOUT, Pngcrush, Zlib, Winrar, Winzip,
Sensor TRANSMISSION Reconstructed
Data Data
Compressed Compressed
Data Data
Compressor Decompressor
Storage

6. Lossy and Lossless
SL
4.6
 Lossless
 Lossless compression enables user to compress the size of
animation without affecting the quality.
 Resulting much smaller compression ratio.
 Uses Run Length Encoding
 E.g:
WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWW
WWWWWWWWWWWWWWWWWWWWWBWWWWWWWW
WWWWWW
 =12W 1B 12W 3B 24W 1B 14W

7. Run Length Encoding
SL
4.7
7 4 2 7 3
Compression in Run Length Encoding
ABBBBBBBBBCDEEEEF
Using RLE compression, the compressed file takes up 10 bytes and
could look like this:
A *8B C D *4E F

8. Lossy and Lossless
SL
4.8
 Lossy
 Lossy compression can reduce the size of file smaller than
lossless compression.
 Resulting much larger compression ratio.
 Erasing some bit data may result low quality display in
animation.
 Eg: JPEG
Original Image High compression
(lossless PNG, 60.1 (98% less
KB size) — information than
uncompressed is uncompressed
108.5 KB PNG, 1.14 KB

9. Compression/Decompression Standard
SL
4.9
 Motion Picture Expert Group (MPEG)
 MPEG use asymmetric algorithm where the mathematical
instructions will determine data for each frames.
 MPEG will only recording location and moving object only,
while static images will be recorded once and be used over and
over again.

10. Compression/Decompression Standard
SL
4.10
 Cinepak
 Using vector algorithm compression where it enables video
clip or animation be played at a fast rate.
 Cinepak is a QuickTime software

11. Compression/Decompression Standard
SL
4.11
 Apple’s QuickTime
 Using lossy compression, it can produce compression at a ratio
5:1 up to 25:1.
 Advantages:
 Plug-in for QuickTime (known as QuickTime Players) distributed
free of charge.
 Does not require special equipment for playback or distribution.
 Disadvantages:
 Small display area.
 Requires large RAM and hard disk because of its large size of file.

12. Compression/Decompression Standard
SL
4.12
 SWF - Shockwave Flash
 Advantage : File size is small for a complex
animation
 DCR – Interactive in nature
 Developed by Macromedia Director
 Used for distribution through web, due to its
file size

13. Compression/Decompression Standard
SL
4.13
 MOV –
 Use to distribute animation file in video format
 Advantages :
 cross platform
 good quality of audio and video
presentation
 AVI - Audio Video Interleave
 distributing animation file in video format
 quality of presentation is less compared to MOV

14. Compression/Decompression Standard
SL
4.14
 MPEG - to set standards for audio and video
compression and transmission
 Have several levels of functionality:
 MPEG-1: Initial video and audio compression standard, used
as the standard for Video CD and Layer 3 (MP3) audio
compression format
 MPEG-2: video and audio standards for broadcast quality
television. Used for digital television, digital satellite TV
services, digital signals, and for DVD video discs.

15. Compression/Decompression Standard
SL
4.15
 MPEG-4: Expands MPEG-1 to support video, audio or 3D
content.
 MPEG-7: A formal system for describing multimedia content.

16. Compression/Decompression Standard
SL
4.16
 GIF
 Factors that make GIF most commonly used:
 Support transparency to image.
 Animation played non-stop.
 Cross-platform.
 Doesn’t require any kind of plug-in.
 Disadvantages:
 Not supporting audio file format.
 No interactivity.
 Only 256 colors.