Page 198 - DCAP303_MULTIMEDIA_SYSTEMS

Multimedia Systems

notes self assessment

Choose the correct answer:

5. ……………… is a central issue in digital image compression.
( a) Data compression (b) Data redundancy
( c) Multi redundancy (d) None of these
6. Coding process would alter the level of correlation between the pixels within the images.

( a) True (b) False
7. ………………. includes a channel decoder followed by a source decoder.
( a) Encoder (b) Decoder

( c) Model (d) None of these
8. Run-length coding is an example of a mapping.
( a) True (b) False

11.6 summary

• The codec is a short name for coder-decoder that takes a raw data file and turns it into a
compressed file.

• In lossless compression, both original data and the compressed data are the same.
• Data redundancy is a central issue in digital image compression.
• A compression system consists of two distinct structural blocks: an encoder and a
decoder.
• A variable-length code is used to represent the mapped and quantized data set.

11.7 Keywords

Codec programs: They are required for your media player to play your downloaded music and
movies.
Lossless compression: It is used to removing the redundant data in the compression and adding
them in the decompression.
Lossy compression: It is the compression technique which will lose data in the original source
while trying to keep the visible quality at the almost same amount.
Multimedia compression: It is employing tools and techniques in order to reduce the file size
of various media formats.
source encoder: The source encoder is responsible for reducing or eliminating any coding,
interpixel or psychovisual redundancies in the input image.

1. Give the steps to reduce the code redundancy.

2. Create a general compression system model for an image.

192 LoveLy professionaL University