Media bias is reflected in more than just words. In this example above, the Photo Editor at Fox News could have chosen any picture from this press conference to depict the president. They intentionally chose a supremely unflattering one to make the subject appear a particular way - stupid, angry, silly. etc. This form of bias can be more damaging than words in our image-driven world.
In an opinion piece this editorial choice can be accepted. In a news piece it shows a lack of professionalism and intention to persuade or manipulate the viewer's perspective or view of the subject.