Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Image Compression idea

Status
Not open for further replies.

Indian

Junior Member level 3
Joined
Jun 2, 2005
Messages
26
Helped
1
Reputation
2
Reaction score
0
Trophy points
1,281
Activity points
1,539
Regarding image compression i thought of an idea please reply me whether its existing or not or its useless.
The idea is i am going to divide the total image into blocks. In each and every block i will determine all the different color values present there and then i will enter the color values into a table linking with a lower symbol consisting of less no of bits then the orginal and the replace the values in the block with there corresponding sysmbols. here no loss of data so the precision of the image can be maintain, but it will fails when all the values present in the block are diff, but in most of the case it will not be so

Thanks
 

artem

Advanced Member level 4
Joined
May 22, 2003
Messages
1,350
Helped
126
Reputation
252
Reaction score
32
Trophy points
1,328
Location
Turkey
Activity points
13,461
I think hafman codes are little bit similar with what you have described.
 

MirekCz

Junior Member level 2
Joined
Aug 23, 2005
Messages
24
Helped
4
Reputation
8
Reaction score
4
Trophy points
1,283
Location
Poland
Activity points
1,524
I don't understand your description exactly, but it seems like a form of waveform encoding... read up on it if you're interested.

And it's Huffman encoding
 

artem

Advanced Member level 4
Joined
May 22, 2003
Messages
1,350
Helped
126
Reputation
252
Reaction score
32
Trophy points
1,328
Location
Turkey
Activity points
13,461
MirekCz said:
I don't understand your description exactly, but it seems like a form of waveform encoding... read up on it if you're interested.

And it's Huffman encoding

Sorry for wrong writing - huffman .


Excerpt from Robert Sedgewick's book "Algorithms" :

"The Huffman code achieves economy in space by encoding
frequently used characters with as few bits as possible so that the total number
of bits used for the message is minimized....

The first step is to count the frequency of each character within the
message to be encoded...

The next step is to build a “coding tree” from the bottom up according
to the frequencies. (character)"
 

emrek

Member level 2
Joined
Jul 26, 2004
Messages
48
Helped
4
Reputation
8
Reaction score
0
Trophy points
1,286
Activity points
462
Hi,

Actually your idea can be used in all kinds of files (not only in images). Because in all of them there is an encoding in order to store the data (ie. ascii code). As far as I understand you are trying to optimize this encoding process. In a simple way you can check efficiency of your idea by comparing with another lossless compression algorithm. For example try winzip. I do not really know but probably these algorithms also use approaches similar to yours.
 

mro83

Member level 5
Joined
Oct 6, 2004
Messages
86
Helped
11
Reputation
22
Reaction score
4
Trophy points
1,288
Location
Mashad
Activity points
758
Hi
regarding to ur question as a source coding (compression ). Lempel-Ziv coding is more optimum from Huffman coding.
 

pengyou54

Newbie level 5
Joined
Nov 27, 2005
Messages
10
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,415
As for image compression, the most popular codec is JPEG200, which uses wavelet transform. I think usually an image compression book will introduce a lot of methods used.
 

itsthetimetodisco

Member level 4
Joined
Jul 21, 2006
Messages
76
Helped
7
Reputation
14
Reaction score
6
Trophy points
1,288
Activity points
1,666
Opt JPEG2000...the best encoding technique for still images as of now.
 

vadkudr

Advanced Member level 4
Joined
Jul 12, 2005
Messages
109
Helped
15
Reputation
30
Reaction score
4
Trophy points
1,298
Activity points
2,236
I think that author should learn more about lossless and lossy compression methodology.
See for example

Proceedings of SPIE
Volume 3970 -- Media Processors 2000
Computationally efficient lossless image coder
Parthasarathy Sriram and Subramania I. Sudharsanan
pp. 50-58
 

yok

Member level 3
Joined
Jul 27, 2006
Messages
59
Helped
11
Reputation
22
Reaction score
3
Trophy points
1,288
Activity points
1,639
Friend, a good introduction is "Introduction to Data Compression" 2nd Edition by Sayood
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top