How can enforce a size of an image uploaded?

I want clients to upload images on my form . but i want to be a minimum of 3000 x 3000 pixels . also how can i allow wav file uploads instead of mp3 uploads ?

This is not possible to enforce the image size in pixels, but you can set a minimum file size. For example, if you use a 3072 KB value, the minimum file size will be 3 MB.

Guide:

Changing the File Upload Size Limit

And you can also control what file types can be uploaded, please see:

How to Change the Allowed File Types in the Upload Field