Flag icons are image quality warnings. On occasion when filling in a photo, a blue warning sign will appear on the border of the picture. This warning indicates that the quality of the photo may not be high enough for printing purposes. It is recommended that the photo be made smaller until the warning sign disappears (best quality) or slightly bigger than this size (if it is required for your page layout design). A red warning sign indicates that the picture quality is significantly lower than recommended for printing purposes - the image therefore needs to be reduced considerably in size or replaced with another image.