Unfortunately, if you can still view menus, icons and material recorded before the problem started, then, the symptoms indicate that there is a problem with the ccd (the light sensitive chip that produces the image) or the connection to it. Canon repair is generally the only option and while your camera was
on the list of Canon cameras for possible free repair, the information at the links below do fully explain the problem and tells how Canon handled it. Since more and more newer models have the identical problem the info may give you some leverage with Canon since it is not under warranty. You are now the 5th person in a three month period, with a digital camera that I have advised of this problem. Click on or copy and paste the links into your browser
I give the information below as an example. Over the years, I've seen the problem be both progressive or sudden in pretty much equal frequency. Canon UK basically dropped any acknowledgment of the issue for all model well over a year before the US and Japan did in 2012, but the technical description is still very good. The only real cure has been the replacement of the image sensor. While I do not recommend it, I have purchased a number of older cameras displaying this problem and have been able to temporarily restore them with a few good whacks. The results are random.http://www.usa.canon.com/cusa/support/consumer/digital_cameras/powershot_a_series/powershot_a70?pageKeyCode=prdAdvDetail&docId=0901e024801e74fe
Please keep in mind that my diagnosis & solutions provided are directly dependent on the accuracy of your description of the problem. As with any "do it yourself" fixes, success is a "team effort", since I can't see or touch the camera, and relies on the customer's manual dexterity and ability to follow the instructions well.
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