A blank canvas is the classic image of possibility, so it is read as a fresh start or a creative opening. Canvas as tent or sail adds readings of shelter and adventure.
When this appeared in your dream, what were you feeling?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.