Creating Image Thumbnails - BASICS?

[SoLoGHoST]

Ok, I am interested in creating thumbnails (already have a function to resize the thumbnail, keeping the same aspect ratio).  Basically I'm looking for a step by step instructions for creating thumbnails using the gd library.  I don't need details on this, just a general approach, something like this:

1. Obtain a handle to the image
2. Get mime type and be sure it is an image, nothing else
3. check the width/height of it if image
4. if width/height is bigger than dimensions allowed do resize of temporary image, apply resize function, etc. etc..
5. Create a true color image from the result
6. Move this image to the appropriate thumbnail folder...


Ok, I know I'm missing steps here, so kinda hoping someone can fill in the gaps...

Thanks

Also, not needed, but would be awesome if you were to provide the php functions, if any, that fall within that instuctional step, or category.

Thank You Very Much!

[SoLoGHoST]

Ok, topic has been solved here ==> Thumbnail Creation

Thanks Tenma