wkhtmltopdf - wkhtmltoimage - image is not being resized

Question

I'm trying to create an image with custom width like 289. The problem is that appears that minimum size is 550. If i choose a size lower then it, the wkhtmltoimage just 'cut out' a part of my image instead do a resizing.

Anyone knows how to force resize instead 'cut out' the image?

Here is the command that i'm using:

khtmltoimage.exe --disable-smart-width --custom-header "
   User-Agent" "Mozilla/5.0 (iPhone; U; CPU iPhone OS 3_0 like Mac OS X; en-us)  
  AppleWebKit/528.18 (KHTML, like Gecko) Version/4.0 Mobile/7A341 Safari/528.16" 
  --custom-header-propagation c:\tmp\test2.html c:\tmp\test5.png