Code covered by the BSD License

Highlights from
Quadtree decomposition (Encoding) and Decoding of RGB Image

A =padtomakepowof2(A,varargin... % if required then add padvalue (defualt 0)
I=qtreedecode(S,values) % Decode QuadTree Represenation of Image given as Sparse matrix 'S' and
I=qtreergbdecode(S,valRGB) % Decode QuadTree date that is decomposed (encode) by qt3ddecom method
S=trimsparse(S) % trim sparse matrix by removing extra rows/columns that have all elements zeros.
[S,keys]=delsparsekeybyxANDy(...
[S,valRGB]=qt3ddecom(I,vararg... % This method uses three thresholds for red,green and blue blocks.
[b1r,b1c,b2r,b2c,b3r,b3c,b4r,... % The method uses three thresholds for red,green and blue blocks.
[b1r,b1c,b2r,b2c,b3r,b3c,b4r,... % given the size of rectangle (matrix end points), it split into four
avg=avgofmatblks(mat,i,j,w,h) % finds average of different blocks of input matrix
drawquadblocks(S) % draw square quad blocks of quadtree in eight basic colors.
fillrect_ulwh(ul,w,h,varargin... % fill the rectangle region specified by upper left corner width
flag=ispowerof2(n)
rgbimgnew =padrgbtomakepowof2... % if required then add padvalue (defualt 0)
var=converttoclass(var,type)
main.m
View all files

4.5

4.5 | 8 ratings Rate this file 28 Downloads (last 30 days) File Size: 463 KB File ID: #9485

Quadtree decomposition (Encoding) and Decoding of RGB Image

by Dr. Murtaza Khan

02 Jan 2006 (Updated 26 Aug 2010)

Quadtree decomposition (Encoding) and Decoding of RGB Image of size M-by-N-by-3.

| Watch this File

File Information

Description

Quadtree decomposition of RGB image of size M-by-N-by-3. Three thresholds for red,green and blue components are used. For any R or G or B block if the maximum value of the block elements minus the minimum value of the block elements is greater than its respective threshold then the RGB block is split into 4 blocks. For lossy encoding (individual) mean value R,G,B are assign to RGB block. Image is padded if its size is not power of 2, so that image can be divided until block of size 1.

Thresholds are specified as a value between 0 and 1 (0 for lossless encoding). If Image is of type uint8 then threshold value is multiplied by 255, if Image is of type uint16 then threshold value is multiplied by 65535, to determine the actual threshold. No toolbox required.

main.m
---------
Test program for Quadtree decomposition (Encoding) and Decoding of RGB image

reference
------------
Murtaza Khan and Yoshio Ohno, "A hybrid image compression technique using quadtree decomposition and parametric line fitting for synthetic images". Advances in Computer Science and Engineering, 1 (3), pp. 263-283, Nov. 2007.

MATLAB release

MATLAB 6.5 (R13)

Tags for This File
Everyone's Tags	compression(3), decoding, encoding, image, image analysis, quadtree, rgb, true color
Tags I've Applied
Add New Tags	Please login to tag files.

Please login to add a comment or rating.

Comments and Ratings (16)
29 Jun 2012	Carlos
02 Apr 2012	Tejaswini K	how to convert this matlab code to verilog.. or vhdl
20 Aug 2010	Stacy Ross	I just downloaded your program. And testing with main.m and your rafting image, I get two errors: ??? Undefined function or method 'delsparsekeybyxANDy' for input arguments of type 'double'. Error in ==> qt3ddecom at 133 [S,valRGB]=delsparsekeybyxANDy(S,i,j,valRGB,ir,ic); Error in ==> main at 11 [S,valRGB]=qt3ddecom(I,thvec); %lossy encoding Best, Stacy
20 Jul 2009	Dr. Murtaza Khan	New version has been uploaded. Fee free to use and comment on this program. Thanks Author
18 Jul 2009	Dr. Murtaza Khan	I updated the new version on 18-July, which includes two missing files delsparsekeybyxANDy.m and trimsparse.m. Please wait few days so that Matlab can approve and upload the new version in few days. thanks Author
30 May 2009	hbu	excellent
24 Apr 2009	Robin	Really good work !!! would you please send me the qt3ddecomp m-file ? thank you so much Robin
15 Apr 2009	Pierrick Gérenton	good work !!! would you please send me the qt3ddecomp mfile ? thank you
02 Apr 2009	yxlvvv i	great work would you send me the mfile from qt3ddecomp.p please...,my e_mail:yxlvvv@qq.com thank you
24 Nov 2008	Basheer	great work would you send me the mfile from qt3ddecomp.p please...???
24 Oct 2008	Saksono Setiardi	may i have the mfile from qt3ddecomp.p please...???
22 Sep 2007	selma salem	can I have a mfile qt3ddecomp to better understand a method.
02 Jul 2007	Taner Ince
26 Feb 2007	vidya krishnamurthi	its very useful to me thank u
04 Jan 2006	J. Tai	Neat, works very well.
03 Jan 2006	Eugene Konoplin

Updates
05 Jan 2006	punctuaton correction and better description. No change in files.
03 May 2006	updated
09 Jul 2009	BSD License
18 Jul 2009	Missing files are included
01 Jun 2010	Reference of my research work and my research paper is included
26 Aug 2010	Two missing files are added

Highlights from Quadtree decomposition (Encoding) and Decoding of RGB Image

Quadtree decomposition (Encoding) and Decoding of RGB Image

Highlights from
Quadtree decomposition (Encoding) and Decoding of RGB Image