Exif Data Error - Incorrect APP1 Exif Identifier Code

Question

Hi,

In my PHP app, I am retrieving exif data from uploaded images.

I am performing the PHP exif_read_data function on images but some throw the following error - [<a href='function.exif-read-data'>function.exif-read-data</a>]: Incorrect APP1 Exif Identifier Code

I think that these images that have been processed through software after being taken. Any idea how I can get around this error? Is there a way to test whether the exif data array returned contains valid data?

Thanks.