help with the image reference

Ok so im trying to find how to use the image reference tab. Now if I remember this will fix onto the camera viewport’s aspect ratio that you set the camera too, is this true. Also. Is it possible to uuse an animated avi file as a reference image that changes every frame on the blender timeline?

You mean in the N panel the “Background images” thing?
Put the viewport in camera mode (numpad 0)
Open the N panel and check Background Images.
Press the button to add image and select as axis: Camera
Then press Movie clip and Open your movie. Uncheck “camera clip”. Put the opacity to 1.0 or what you want and press Back or Front as you want…