Methods and systems for improving encoding of a picture or a frame are disclosed. According to one embodiment, a method for encoding video frames includes receiving for a frame, several binarized symbols that include a number of bins corresponding to one or more contexts. For each context from one or more contexts, the method includes entropy encoding in a first pass bins associated with the context using an initial probability distribution for the context; generating counts of zeros and ones in a set of bins associated with the context; updating the initial probability distribution using the respective counts of zeros and ones, to obtain an updated probability distribution; and entropy encoding in a second pass the bins associated with the context using the updated probability distribution, to provide at least a part of an encoded bitstream.