read image using url failed..

[sntsnt8]

Hi,

I tried very simple code to read an image from url but failed.
My code is

Image image("styles/subsilver2/imageset/site_logo.png");
cout << image.columns() << " " << image.rows() << endl;
image.scale("20%");
image.write("1.jpg");

I find that the image column and row are all 0
therefore the write() will have a memory allocation exception.

I hope someone can tell me how to fix this problem.
Thanks

[sntsnt8]

Beside, if I use the convert executable, it works....
So I don't know why my code cannot work...

[sntsnt8]

i find the reason is i'm missing the xml lib...