TIFF image manipulation

[Anon]

Hi all,
I'm working on a page that allows users to upload either a JPEG or TIFF. The upload part works, but the PHP page must then:

determine whether or not the image is > 200dpi,

determine whether the image is a jpeg or tiff,

create a thumbnail image which is grayscale, and return the thumbnail image to the screen.

I know i can use image magic's convert to change a tiff to a grayscale jpeg thumbnail, but how do i know if it's a tiff?

Thanks in advance,

Ben

[Anon]

Try to GetImageSize() it. If GetImageSize fails then it is not JPEG, GIF, PNG or SWF image.

You can use @GetImageSize to surpress the actual error msg if it's a tiff.

Not the best solution but it should work. A better solution would be to write a little c prog using magick++ that would just do the conversion for you whether it is jpeg or tiff.

Note: I would assume checking the file extension isn't enough?

Jack

[Anon]

thanks for the advice.

I still need to be able to find out the reolution (not the image size).

the file extensions often aren't representative of the file, and from everything i've read, a Mac won't return a file extension, so I have to delve into the file itself to ectract the info.