I have an application that allows users to upload images. The test case I use is a jpeg of 1.6MB with dimensions 3872 x 2592px. The upload script in the back-end will resize the uploaded image into 6 additional formats:
- square (small 75 x 75)
- Small Thumb (50 x 38)
- Thumb (100 x 76)
- Small (240 x 161)
- Medium (500 x 378)
- Large (1024 x 774)
I know it's a lot but trust me, I need this. I do the resizing using Code Igniter's Image Manipulation class, which uses either GD, GD2 or ImageMagick to do the resizing. I first configured it to use GD2 and noticed that the total resize process takes 11 secs.Since the user has to wait for this process, it is not acceptable. After a lot of reading I learned that ImageMagick is a much faster and efficient manipulation library, so I switched to that:\[code\]$sourceimage = $data['filedata']['file_path'] . $data['imagedata']['user_id'] . "/" . $imageid . $data['filedata']['file_ext'];$resize_settings['image_library'] = 'imagemagick';$resize_settings['library_path'] = '/usr/bin';$resize_settings['source_image'] = $sourceimage;$resize_settings['maintain_ratio'] = false;$resize_settings['quality'] = "100%";$this->load->library('image_lib', $resize_settings);\[/code\]Much to my surprise, the resize process now takes longer: 15 secs to be specific.Having a look at my log I see that each resize action takes 2 seconds, no matter the file format it is resizing to. I guess this is because I always resize from the original, which is very large. I would hate to offload the resizing process to a scheduled process, because that would decrease the usability of the site. It would mean that users have to wait a few minutes before they can start seeing/working with the image.
So, are there any smart ways to dramatically speed up this resizing process so that I can keep it in real-time? Just be clear: allowing for smaller resolutions is not an option, this is a photography site I'm building. Also, I really need the six formats mentioned.
