
		<paper>
			<loc>https://jjcit.org/paper/54</loc>
			<title>A COMPARATIVE STUDY OF DCT AND DWT IMAGE COMPRESSION TECHNIQUES COMBINED WITH HUFFMAN CODING</title>
			<doi>10.5455/jjcit.71-1554982934</doi>
			<authors>Ashraf Maghari</authors>
			<keywords>Image compression,DCT,DWT,Huffman coding,PSNR,SSIM.</keywords>
			<citation>16</citation>
			<views>6015</views>
			<downloads>1478</downloads>
			<received_date>2019-04-11</received_date>
			<revised_date>2019-05-27</revised_date>
			<accepted_date>2019-06-09</accepted_date>
			<abstract>Image  compression  techniques  have  been  widely  used  to  store  and  transmit  data  which  requires  storage  space 
and  high  transfer  speed.  The  explosive  growth  of  high-quality  photos  leads  to  the  requirement  of  efficient 
technique  to  store  and  exchange data  over  the  internet.  In  this  paper,  we  present  a  comparative  study  to 
compare  between  the  Discrete  Cosine  Transform  (DCT)  and  Discrete  Wavelet  Transform  (DWT)  algorithms  in 
combination  with  Huffman  algorithm;  DCT-H  and  DWT-H.  The  comparison  is  based  on  five  factors: 
Compression  Ratio  (CR),  Mean  Square  Error  (MSE),  Peak  Signal-to-Noise  Ratio  (PSNR),  Structural  Similarity 
Index Measure (SSIM) and compression/decompression time. The experiments are conducted on five BMP gray-
scale  file  images. We  found  out  that  DWT-H  coding  is  comparable  to  DCT-H coding in  term  of  CR and 
outperforms DCT-H in terms of MSE, PSNR and SSIM. The CR average results of the five test images for DCT-
H  and  DWT-H  are  2.36  and  3.17, respectively.  Moreover,  DCT-H  has  the  average  results  of  MSE  =  13.19, 
PSNR = 37.15 and SSIM = 0.76, while WDT-H has the average results of MSE = 4.54, PSNR = 42.5 and SSIM 
=  0.85.  On  the  other  hand,  DCT-H  outperforms  DWT-H  in  term  of  execution  time  for  compression  and 
decompression.  DCT-H  has an average  compression  time  of  0.358s  and an  average decompression  time of 
0.122s, while WDT-H has 2.38s compression time and 2.13s decompression time.</abstract>
		</paper>


