# image/PC

**URL:** <https://psychtoolbox.discourse.group/t/image-pc/1677>\
**Category:** Uncategorized\
**Created:** [January 4, 2001, 5:54pm UTC](https://psychtoolbox.discourse.group/t/image-pc/1677 "2001-01-04T17:54:07Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Allen\_Ingling](https://avatars.discourse-cdn.com/v4/letter/a/a183cd/32.png) [@Allen\_Ingling](https://psychtoolbox.discourse.group/u/Allen_Ingling)\
**Post date:** [January 4, 2001, 5:54pm UTC](https://psychtoolbox.discourse.group/t/image-pc/1677/1 "2001-01-04T17:54:07Z")

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Hi all,  
I am using the psychtoolbox with windows 98 and encounter problems   
while presenting an image. It's a simple white on black background   
texture. However, trying to display it with 'PutImage' after reading   
it into MatLab gives me always the reversed pattern, e.g. black on   
white background.  
I tried the uint8 class and the double as well (double(X)\*255). Is   
there any way to force the PC to display 255 as black and 0 as white.   
'SetClut' and chaging the White/BlackIndex files didn't work.  
Thanks for any help,  
Bjoern