The principle of PHP text to image function

This article mainly introduces the principle and implementation method of PHP text to image function, and analyzes the relevant configuration and usage of PHP based on the gd2 extension library to generate images based on specific examples. Friends in need can refer to the following

Details are as follows:

This function is mainly used to process important information such as email addresses, mobile phones, etc. that may be crawled by web crawlers. It's definitely a good idea to convert text into images. The basic generation principle of the verification code is similar to this, but the generation process of converting text into images is further complicated, making it impossible for scanning machines to recognize it. Converting text to images in php is very simple. First open php.ini in the php installation directory, find extension=php_gd2.dll, remove the quotation marks in front of it, open php's gd2 extension library, and you can use it directly. PHP keyword to convert text into images.

The directory structure is as follows. img_generator.php is the php used to convert text to images, and index.html is the page presented to the user.

#index.html code is very, very simple. Create an img tag, write img_generator.php in the src, and then send it to img_generator.php with a text parameter. A Get request, the img_generator.php page is essentially a picture generated based on parameters.

The code of img_generator.php is as follows, get the img tag in index.html through $_REQUEST["text"]; The passed text is described, and then a series of PHP keywords are used, which is the image generated by the inherent method.

In essence, the principle is the same as in "php voting system: adding and deleting votes (administrator)".

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