Enable PHP GD library support under Linux

 php5 -m | grep -i gd
 or
 php -i | grep -i --color gd

2. If the GD library is not installed, install it on the server. Method as follows

# If it is a source code installation, add the parameter
 --with-gd
# If it is a Debian Linux system, use apt-get to install it, as follows
 apt-get install php5-gd
# If it is For a CentOS system, use yum to install it, as follows
 yum install php-gd
# If it is a suse-based Linux system, use yast to install it, as follows
 yast -i php5_gd

3, you can compile it in the original PHP does not support GD appending First download the zlib source code, libpng source code, and gd source code After unzipping, go to the source code directory zlib directory

 ./configure --prefix=/usr/local/zlib
 make ; make install
 make clean

libpng directory

 cp scripts/makefile.linux ./makefile
 ./configure --prefix=/usr/local/libpng
 make ; make install
 make clean
 # gd directory
 ./configure --prefix=/ usr/local/libgd --with-png=/usr/local/libpng
 make ; make install
 make clean

Finally, in php.ini, after searching for [gd], click below add a line

extension=/usr/local/libgdgd.so

Then restart the php service. If it doesn’t work, try reboot. There should be no problem.

Problem analysis: In the case of source code installation, only the gd library is added, the PHP version and the library version are different, so: - There’s no guarantee that you’ll get anything back after putting in so much effort. - Successful loading of gd.so is not guaranteed - No guarantee against pregnancy Therefore, if it is a source code installation, it is best to add the parameter --with-gd when compiling PHP

In addition, enable PHP’s GD library support under Windows. The operation method is as follows: Find php.ini, open the content, and find:

;extension=php_gd2.dll

Remove the semicolon ";" at the front and save it. If there is no semicolon in the first place, it means it has been turned on.

>>> Further reading: php GD library code to upload images and create thumbnails Example of php GD library generating verification code Solution to Chinese garbled characters in php GD library Example of php verification code (GD library generates verification code) Introduction to how to enable gd2 extension in php How to install php GD support library under linux Example code for drawing 24-hour histogram using php GD library Example code for dynamically generating line charts with PHP GD library PHP thumbnail generation class (supports imagemagick and gd libraries)