How can I change the picture where the Cd cover is meant to be on itunes?

On itunes I can view my songs by looking at the CD covers but not all of them have a picture on them how do i change this to a picture on a file on my computer??How can I change the picture where the Cd cover is meant to be on itunes?
right click the song and go to the artwork tab and press add and choose the picture you want.



if you want to do this for multiple songs at once

select them, right click and press get info, then double click in the artwork boxHow can I change the picture where the Cd cover is meant to be on itunes?
right click on the song



click the top option, 'Get Info'



then click on the artwork tab, and click 'Add'



then find the image you want, click OK,



click on the image and then click OK



there you have album artwork from your PC/Mac



help this helps