STEP 1: CREATE A DATABASE

CREATE DATABASE restfulapi;
STEP 2: CREATE A TABLE NAMED tbl_other_photos with params:- id, title, download_link and img_url
CREATE TABLE IF NOT EXISTS `tbl_other_photos` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `title` varchar(255) NOT NULL,
  `download_link` varchar(255) NOT NULL,
  `image_url` varchar(255) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=1 ;

STEP 3: Insert dummy values into the database – you can create a real HTML form to collect data but in this tutrial i will manually insert the data into our table

INSERT INTO `tbl_other_photos` (`id`, `title`, `download_link`, `image_url`) VALUES
(1, 'Mt View Retreat', 'http//:g-photos.com/retreat', 'http//:placeholder.com/img1.jpg'),
(2, 'Summer Games', 'http//:g-photos.com/sports', 'http//:placeholder.com/img2.jpg'),
(3, 'Health Meetup', 'http//:g-photos.com/health', 'http//:placeholder.com/img3.jpg');

STEP 4:- CONNECT TO THE DATABASE AND SELECT INSERTED VALUES

<?php
include_once "../includes/config.php";

header("Content-type:application/json");

 //database configuration
    $host       = "localhost";
    $user       = "root";
    $pass       = "";
    $database   = "restfulapi";

$result = mysqli_query($connect, "SELECT * FROM tbl_other_photos"); 

while($row = mysqli_fetch_assoc($result)){ 
$output[]=$row; 
} 

print(json_encode($output, JSON_PRETTY_PRINT)); 

mysqli_close($connect);

?>

Response will be

[
    {
        "id": "1",
        "title": "Mt View Retreat",
        "download_link": "http\/\/:g-photos.com\/retreat",
        "image_url": "http\/\/:placeholder.com\/img1.jpg"
    },
    {
        "id": "2",
        "title": "Summer Games",
        "download_link": "http\/\/:g-photos.com\/sports",
        "image_url": "http\/\/:placeholder.com\/img2.jpg"
    },
    {
        "id": "3",
        "title": "Health Meetup",
        "download_link": "http\/\/:g-photos.com\/health",
        "image_url": "http\/\/:placeholder.com\/img3.jpg"
    }
]

SEE DEMO HERE