Even if you are installed php with gd, error message ” undefined function imagecreatefromjpeg () ” may appear on php. specifically when installing fresh opencart web application you may definitely face this issue as I did. In Opencart installation process, installer itself checks whether gd is installed, but unfortunately not identify the other important packages such as libJPEG and libPNG are installed or not. Here is how I fixed the that error on Centos.
(01) Install libjpeg and freetype
yum install libjpeg-devel
yum install freetype-devel
For Ubuntu :-
apt-get install libjpeg-dev
apt-get install libfreetype6-dev
(02) Configure and compile php
***you must clean the php before configuring*
When compile gd extension, use the flag –with-jpeg-dir and –with-freetype-dir
no need to define directory(DIR) location of each flag if you are installed libjpeg and freetype using yum commands, otherwise it may be need to set DIR
location of each.
example php configuration
./configure –with-gd –with-jpeg-dir –with-freetype-dir
(03) Restart Apache
below is the sample output of php info file after successful installation.