Does anyone have source data for any standard image compression images such as "Lena" in integer/unsigned char format? If not - is there an easy way I can obtain this by opening an image in Matlab? Cheers Gary
"Lena" or similar compression tests
Started by ●March 17, 2008
Reply by ●March 17, 20082008-03-17
Gary this is easy to do in matlab. you should have image processing
toolbox. if u do not have matlab + ip toolbox, you can use scilab + SIVP
which is completely free.
in matlab you need to do:
rgb = imread('filename.bmp', 'rgb');
rgb will be a 3D array of red, green and blue
color data (8 bit for each color), if you want
individual colours you can write
red = rgb(:,:,1);
grn = rgb(:,:,2);
blu = rgb(:,:,3);
for further processing you can do
rgb_dbl = im2double(rgb);
this will convert it to double data format for processing.
for displaying image:
imshow(rgb);
for writing back image to file
imwrite(rgb, 'filename.bmp');
for compression you need to write the image
data in jpeg format specifying the compression
ratio on the command line. for exact syntax
use
help imwrite
once you write image to disk you can read it
back in matlab for further processing.
%------------------------------------
when u need help on any command in matlab
say
help command_name;
Regards
Bharat Pathak
www.Arithos.com
~dsp Simplified
----------DSP DESIGN CONSULTANCY AND TRAINING COMPANY-------------
>Does anyone have source data for any standard image compression images
>such as "Lena" in integer/unsigned char format?
>
>If not - is there an easy way I can obtain this by opening an image in
>Matlab?
>
>Cheers
>Gary
>
Reply by ●March 18, 20082008-03-18
To add some historical spice, ever wonder who the "lena" girl really is? And why she is smiling? It's worth clicking on the link: http://en.wikipedia.org/wiki/Lenna
Reply by ●March 18, 20082008-03-18
Reply by ●March 19, 20082008-03-19
On Tue, 18 Mar 2008 19:19:53 -0500, "SteveSmith" <Steve.Smith1@SpectrumSDI.com> wrote:>To add some historical spice, ever wonder who the "lena" girl really is? >And why she is smiling? It's worth clicking on the link: > > >http://en.wikipedia.org/wiki/LennaShe'll always be "girl in hat" to me. ;) I was looking for some pics from when she was a guest at SIST in 1997, but I can't find any. And, dayum, was that really eleven years ago? Eep. Eric Jacobsen Minister of Algorithms Abineau Communications http://www.ericjacobsen.org
Reply by ●March 19, 20082008-03-19
On Mar 19, 9:15 am, Eric Jacobsen <eric.jacob...@ieee.org> wrote:> On Tue, 18 Mar 2008 19:19:53 -0500, "SteveSmith" > > <Steve.Smi...@SpectrumSDI.com> wrote: > >To add some historical spice, ever wonder who the "lena" girl really is? > >And why she is smiling? It's worth clicking on the link: > > >http://en.wikipedia.org/wiki/Lenna > > She'll always be "girl in hat" to me. ;) > ...> I was looking for some pics from when she was a guest at SIST in 1997, > but I can't find any. And, dayum, was that really eleven years ago? > Eep. > > Eric Jacobsen > Minister of Algorithms > Abineau Communicationshttp://www.ericjacobsen.orgTry: http://www.cs.cmu.edu/~chuck/lennapg/lenna_visit.html Dale B. Dalrymple http://dbdimages.com
Reply by ●March 19, 20082008-03-19
On Wed, 19 Mar 2008 10:19:57 -0700 (PDT), dbd <dbd@ieee.org> wrote:>On Mar 19, 9:15 am, Eric Jacobsen <eric.jacob...@ieee.org> wrote: >> On Tue, 18 Mar 2008 19:19:53 -0500, "SteveSmith" >> >> <Steve.Smi...@SpectrumSDI.com> wrote: >> >To add some historical spice, ever wonder who the "lena" girl really is? >> >And why she is smiling? It's worth clicking on the link: >> >> >http://en.wikipedia.org/wiki/Lenna >> >> She'll always be "girl in hat" to me. ;) >> ... > >> I was looking for some pics from when she was a guest at SIST in 1997, >> but I can't find any. And, dayum, was that really eleven years ago? >> Eep. >> >> Eric Jacobsen >> Minister of Algorithms >> Abineau Communicationshttp://www.ericjacobsen.org > >Try: >http://www.cs.cmu.edu/~chuck/lennapg/lenna_visit.html > >Dale B. Dalrymple >http://dbdimages.comYeah, like that! Thanks, Dale. Eric Jacobsen Minister of Algorithms Abineau Communications http://www.ericjacobsen.org
Reply by ●March 20, 20082008-03-20
On Wed, 19 Mar 2008 16:04:38 -0700, Eric Jacobsen <eric.jacobsen@ieee.org> wrote: (snipped by Lyons)>> >>Try: >>http://www.cs.cmu.edu/~chuck/lennapg/lenna_visit.htmlIf I saw Lenna (the "older Lenna" in the above web page) in a bar, I'd **definitely** pressure her to help me put quarters in the juke box so that we could dance. Good God. What a "handsome" woman! [-Rick-]
Reply by ●March 20, 20082008-03-20
Rick Lyons wrote:> On Wed, 19 Mar 2008 16:04:38 -0700, Eric Jacobsen > <eric.jacobsen@ieee.org> wrote: > > (snipped by Lyons) >>> Try: >>> http://www.cs.cmu.edu/~chuck/lennapg/lenna_visit.html > > If I saw Lenna (the "older Lenna" in the above web page) > in a bar, I'd **definitely** pressure her to help me put > quarters in the juke box so that we could dance. > > Good God. What a "handsome" woman!I hope and trust that her grandchildren think so too. Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
Reply by ●March 20, 20082008-03-20
On Thu, 20 Mar 2008 15:30:26 -0400, Jerry Avins <jya@ieee.org> wrote:>Rick Lyons wrote: >> On Wed, 19 Mar 2008 16:04:38 -0700, Eric Jacobsen >> <eric.jacobsen@ieee.org> wrote: >> >> (snipped by Lyons) >>>> Try: >>>> http://www.cs.cmu.edu/~chuck/lennapg/lenna_visit.html >> >> If I saw Lenna (the "older Lenna" in the above web page) >> in a bar, I'd **definitely** pressure her to help me put >> quarters in the juke box so that we could dance. >> >> Good God. What a "handsome" woman! > >I hope and trust that her grandchildren think so too. > >JerryHi Jerry, maybe I'm turnin' into an "ol' fart" but I think Lenna looks better in her recent pictures than she did in her famous picture. Yea, ... I guess I am an ol' fart. [-Rick-]
