In order to best view the images on this site, you should ideally calibrate your monitor. The test pattern below contains 17 boxes ranging from totally black to totally white. To calibrate your monitor, use the brightness and/or contrast controls and adjust your screen so that you (ideally) can see each of the 17 segments as an individual shade of gray. You may also have to fool with the gamma setting of your software. You may find that it is not possible to achieve this result (due to variations in the behavior of individual monitors). If this is the case, just do the best you can, however understand that some images will not look that great if proper calibration cannot be achieved!
There have been some changes to the calibration image as of 14 January, this has been done for several reasons. First, and most importantly, the image is new but it is still 100% correct (as was the older image). The new image is a JPEG format, this makes for a much smaller file. The image has been designed so that the JPEG compression algorthim imparts no degradation whatsoever (the previous image was a bitmap file whic also guarantees no loss). I have also added a "www.RocketRoberts.com" logo to this image. The reason for this is as follows: in looking at web download statistics for my pages, I have noticed that the original file (calbar.bmp) was consistently the file generating the most traffic on my site! The only way this could be possible is that large numbers of external sites are using the file (without consent). Those sites did not copy the file and place it onto their own server, rather they simply added code to their pages that downloaded it from my server. This would be OK with me except for one thing: it steals a significant amount of bandwidth. So, the external sites that use this file (without consent) will no longer show the image (as it has been removed from my sevrer). If they do locate the new image and use it (without consent) it won't be as bad because (1) the new file is one sixth the size of the original and (2) with the logo on the new file at least people will know who the person is who originally generated this test pattern! (Too bad I could not figure a way to get one tenth of one cent each time this image was downloaded... it would be a nice side income!).
The calibration test pattern above was generated by a MATLAB (www.mathworks.com) script I wrote (and by subsequently assembling the MATLAB generated image files in PhotoShop). If you are into MATLAB, the script is presented below FYI. I threw this together very quickly so there are few comments in the code.
x=ones(64,32); % this number (64x32) is critical to keep JPEG compression artifacts at zero.
x000=x.*0/255;
x016=x.*16/255;
x032=x.*32/255;
x048=x.*48/255;
x064=x.*64/255;
x080=x.*80/255;
x096=x.*96/255;
x112=x.*112/255;
x128=x.*128/255;
x144=x.*144/255;
x160=x.*160/255;
x176=x.*176/255;
x192=x.*192/255;
x208=x.*208/255;
x224=x.*224/255;
x240=x.*240/255;
x255=x.*255/255;
imwrite(x000,'c:\aaa\000.bmp','bmp')
imwrite(x016,'c:\aaa\016.bmp','bmp')
imwrite(x032,'c:\aaa\032.bmp','bmp')
imwrite(x048,'c:\aaa\048.bmp','bmp')
imwrite(x064,'c:\aaa\064.bmp','bmp')
imwrite(x080,'c:\aaa\080.bmp','bmp')
imwrite(x096,'c:\aaa\096.bmp','bmp')
imwrite(x112,'c:\aaa\112.bmp','bmp')
imwrite(x128,'c:\aaa\128.bmp','bmp')
imwrite(x144,'c:\aaa\144.bmp','bmp')
imwrite(x160,'c:\aaa\160.bmp','bmp')
imwrite(x176,'c:\aaa\176.bmp','bmp')
imwrite(x192,'c:\aaa\192.bmp','bmp')
imwrite(x208,'c:\aaa\208.bmp','bmp')
imwrite(x224,'c:\aaa\224.bmp','bmp')
imwrite(x240,'c:\aaa\240.bmp','bmp')
imwrite(x255,'c:\aaa\255.bmp','bmp')
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