apache server takes too much time to resize a image

Question

i have a lamp server which runs php script. i use this script https://github.com/blueimp/jQuery-File-Upload/blob/master/example/upload.php which automatically uploads and resize the image to the defined resolution.

i have a problem now. a 5Mb file takes about 6 seconds to finish the full job. if i queue up 10 files for upload the server is not responding for other requests. and the both cores of the processor are at 100% use.

i have the full access to the server. what should i do to reduce the work load of the server. is the problem on the scripts or should i use any pluggins for resizing..

Answer 1

The PHP file you linked uses the imagecopyresampled function, which needs much cpu to do the work. You can use the function imagecopyresized instead, but the resulting quality will be worse then.

Depending on the destination size, you can combine these two, first reduce the pictures size by imagecopyresized half of its size, and use then imagecopyresampled to reduce the size to its final size. This should end in a similar quality as if you would have done it in one step using imagecopyresampled