The state-of-the-art H.264/AVC video codec, recently
adopted as part of the Brazilian Digital TV System, presents a
much improved performance when compared to its predecessors
(e.g. MPEG-2), due in large part to the combined and intensive
use of several coding techniques, such as motion estimation/
compensation, bi-directional prediction etc, albeit at a much
larger computational complexity. In this article, we propose the
inclusion of an additional, standard compliant, mode, in the ratedistortion
optimization loop for the encoding of B-frames. This
mode will allow the encoder to selectively discard transform
coefficients of the prediction residue whenever the associated
D + ¸R cost is smaller than all the other tested modes (e.g.
list0 prediction). Several encoding tests, performed on standard
video sequences, are presented that confirm the potential of the
proposed method.