Brits looking to travel abroad are reminded that their passport photo needs to pass several criteria or it could be rejected. Providing a photo is a vital step in the process of applying for a passport.

Without it you would not be able to carry on with the application. However, it is not just as simple as taking a photograph of yourself.

It must follow several rules or face a delayed or rejected application. The photo can be digital if you are applying online, but must be printed if you are filling out a paper application.

You must also get a new photo when you get a new passport, even if your appearance has not changed. And your photo must have been taken in the last month.

warns: "Your application will be delayed if your photos do not meet the rules."

You can get a digital photo either:

• From a photo booth or shop before applying for your passport
• By taking one using your own device during your passport application.

However, says: "Photos from a booth or shop are more likely to be approved than a photo taken using your own device." If you opt to get the photo taken from a booth or shop you must hoose the option to get a code with your photos.

You'll be asked to enter the photo code during your passport application and your digital photo will be added to your application.

But if you're choosing to take your own photo you'll need someone to help you take a photo during your application.

This photo must be:

• Clear and in focus
• In colour
• Unaltered by computer software
• At least 600 pixels wide and 750 pixels tall
• At least 50KB and no more than 10MB.

"If you're using a photo taken on your own device, include your head, shoulders and upper body," the Government website adds. "Do not crop your photo - it will be done for you."

If you are filling out a paper application for a passport you will need two identical printed photos. These must be a close-up of your full head and upper shoulders.

The image of you - from the crown of your head to your chin - must be between 29mm and 34mm high.

The photos must:

• Measure 45 millimetres (mm) high by 35mm wide (the standard size used in photo booths in the UK)
• Not be a cut down version of a larger picture.

says: "If you use a photo booth outside the UK, check it can give you photos that measure 45mm high by 35mm wide."

Your photos must be:

• Printed to a professional standard
• Clear and in focus
• In colour on plain white photographic paper with no border
• Without any creases or tears
• Unmarked on both sides (unless a photo needs to be countersigned)
• Unaltered by computer software.

Whether your picture is printed or digital they must:

• Contain no other objects or people
• Be taken against a plain light-coloured background
• Be in clear contrast to the background
• Not have "red eye".

In your photo you must:

• Be facing forwards and looking straight at the camera
• Have a plain expression and your mouth closed
• Have your eyes open and visible
• Not have hair in front of your eyes
• Not have a head covering (unless it's for religious or medical reasons)
• Not have anything covering your face
• Not have any shadows on your face or behind you.

For more information, visit .