Venetian blind effect ( Anthony 18/6/2008 )

This uses the imagemagick miff which saves the image into the memory and then the Unix "pipe".

IM code:

<?php  
$cmd 
" -size 2x4 xc:none -fill black ".
" -draw \"rectangle 0,0 2,1\" miff:- | ".
" composite -dissolve 30% -tile - input.jpg "
exec("convert $cmd output.png"); 
?> 
Image to go with Venetian blind effect example code