weird borders when scaling an image with css

• Component: Images
• Status: NEW ---

I am scaling two images(jpg) with the following css.

.social_img{
    height:20px;
}

In safari browsers (mac computer(Mavericks 10.9.2), ipad (iOS 7)) I get a thin black line bottom and right. There is nothing in the images. It works fine in chrome and firefox.

For an example see

http://labedzki.se/tests/black_line_test.html