What is the method to get image size in php

In Web development, processing images has become a very basic and essential technology. In PHP, getting the size of an image is also a very important operation. However, if you are a newbie and don’t know much about how to get the image size, then this article will explain to you how to get the image size in PHP.

In PHP, the method of obtaining the image size can be achieved in two ways. The first method is to use the native function library, and the second method is to use a third-party library to obtain the image size. Next we will introduce these two methods respectively.

Use the PHP native function library to obtain the image size

The PHP native function library provides some functions for obtaining the image size, the most commonly used of which is the getimagesize() function. This function returns an array containing the width, height, and type of the image. The following is a simple example:

<?php
list($width, $height, $type, $attr) = getimagesize("image.jpg");
echo "Width: " . $width . " px<br>";
echo "Height: " . $height . " px<br>";
?>

In this example, we use the getimagesize() function to get the size of the image.jpg. The array returned by the function contains four elements, namely the width, height, type and attributes of the image. We use the list() function to assign these elements to $width, $height, $type and $attr respectively.

Use a third-party library to obtain the image size

In addition to using the PHP native function library, we can also use a third-party library to obtain the image size. The more commonly used ones are the GD library and the Imagick library.

Among them, the GD library is an open source library used to create and manipulate images. It provides some functions for processing images, one of which is imagecreatetruecolor(), which can create a TrueColor image resource based on the specified width and height. We can use this function to get the image size, as shown below:

<?php
$img = imagecreatetruecolor(640, 480);
$width = imagesx($img);
$height = imagesy($img);
echo "Width: " . $width . " px<br>";
echo "Height: " . $height . " px<br>";
?>

In this example, we use the imagecreatetruecolor() function to create a 640x480 pixel TrueColor image resource. Then we use the imagesx() and imagesy() functions to get the width and height of the image.

In addition to the GD library, we can also use the Imagick library to get the size of the image. The Imagick library is a powerful image processing library that supports multiple image formats and provides many useful functions for operating images. You can also use the functions in the Imagick library to get the image size, as shown below:

<?php
$image = new Imagick("image.jpg");
$width = $image->getImageWidth();
$height = $image->getImageHeight();
echo "Width: " . $width . " px<br>";
echo "Height: " . $height . " px<br>";
?>

In this example, we use the getImageWidth() and getImageHeight() functions in the Imagick library to get the width and height of the image .

Summary

There are two ways to get the image size in PHP: using native function libraries and using third-party libraries. When using the native function library, we can use the getimagesize() function to obtain the image size. When using a third-party library, we can use the imagesx() and imagesy() functions in the GD library, or the getImageWidth() and getImageHeight() functions in the Imagick library to obtain the image size. Mastering these methods will play an important role in helping web developers process images.

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