The decode resolution of a video signal can be varied during decoding by decoding a first portion of a video signal at a first resolution; determining a second resolution, different from the first resolution, at which a second portion of the video signal is to be decoded; adjusting one or more reference pictures associated with the video signal to correspond to the second resolution; and decoding the second portion of the video signal at the second resolution. The second resolution, at which the second portion of the video signal is decoded, can be selected from a plurality of predetermined decoding resolutions in response to the detection of a predetermined condition or in response to an input received from a user. Additionally, one or more reference pictures associated with the video signal can be up-sampled or down-sampled in at least one of the horizontal direction and the vertical direction.