One of the important algorithm of data structure

1. Huffman
Coding Algorithm
By Mahmudur Rahman shuhin

2. What are Huffman
Codes?

3. “Huffman codes are an
effective technique of ‘lossless
data compression’
Which means no information
is lost.
Huffman code is used to convert
fixed length codes into varible
length codes.
3

4. Why we can use huffman
codes?

5. Consider a file of 100,000 characters from
a-f, with these frequencies:
 a = 45,000
 b = 13,000
 c = 12,000
 d = 16,000
 e = 9,000
 f = 5,000

6.  a = 000, b = 001, c = 010, d = 011, e = 100, f = 101
 This is fixed length code.
 We can encode the whole file with 300,000 bits
(45,000*3+13,000*3+16,000*3+12,000*3+9,000*3+5,000*3)
 We can do :
 Better Compression.
 More Flexibility.

7. Huffman Codes can perform significantly better
 Consider this scheme:
a = 0 ,b = 101,c = 100,d = 111,e = 1101,f = 1100
 How many bits are now required to encode our file?
45,000*1+13,000*3+16,000*3+12,000*3+9,000*4+5,000*4 =
224,000

8. 1.Prepare the freqency table.
2.Construct the binary tree.
3.Extract the Huffman Code from the
tree.
Major Steps
8

9. For Example:
B A G A G G E 100 11 0 11 0 0 101
Plain Text Huffman code
9

10. Steps 1:Create A Frequency Table.
Alphabets Frequencies
b 1
a 2
g 3
e 1

11. 11
Steps 2: Construct the binary tree.

14. Extract Huffman code from the
tree
b 100
a 11
g 0
e 101

15. Application of
Huffman Codes
Support various file type as:
•ZIP
•JPEG
•MPEG
15

16. THANKS!
Any questions?
You can find me at:
suhin4000@gmail.com
16