上载时image_width和image_height为空白（PHP / Codeigniter）

Question

I have an intermittent image uploading issue that I can't seem to track down an answer for. I'm using Codeigniter, but this may just simply be a PHP related issue.

I'm doing simple single image uploads. The files upload just fine in all cases. Then I attempt to access the upload data to determine height and width. Most of the upload data is populated, but height and width are blank. This only happens for some images, others work just fine.

Anyone point me in the right direction? Any thoughts? There's something I'm not seeing here.

Here's an example of the upload data I receive:

[upload_data] => Array (
  [file_name] => example.jpg
  [file_type] => image/jpe
  [file_path] => path/to/file/
  [full_path] => path/to/file/example.jpg
  [raw_name] => example
  [orig_name] => example.jpg
  [client_name] => myPic.jpg
  [file_ext] => .jpg
  [file_size] => 568.02
  [is_image] => 1
  [image_width] =>
  [image_height] =>
  [image_type] =>
  [image_size_str] =>
)

Answer 1

list($width, $height, $type, $attr) = getimagesize("path/for/the/file");

http://www.php.net/manual/zh/function.getimagesize.php

Answer 2

Through a lot of trial and error I found the cause of the issue, but not the solution. However, from what I can tell, the cause is linked to Amazon's S3 storage, not CodeIgniter or PHP. So I'm considering this question answered since it's tagged as a PHP/Codeigniter question.

In a nutshell, here's what I found. Codeigniter uses 'getimagesize' just like you would in straight PHP. So I started testing outside of CI just calling getimagesize on different JPEGS.

When accessing images stored locally on the server/instance, everything works fine, no matter what their properties.

When I access images on Amazon's S3 storage, the JPEGS whose "color representation" property is set to "sRGB" cause getimagesize to return false. Those without the property set work just fine.

So something about storing the images on S3 is causing an issue. But that's the subject of another post.

Thanks for your input on this one everyone.