A device for storing blocks of bits intended to be decoded according to a block decoding algorithm. The blocks are likely to belong to a given category out of a first category and a second category. The first category corresponds to a first given block size, and the second category corresponds to at least one second given block size less than said first block size. The storage device comprises three storage elements having a size suitable for storing one block of the first category each, and at least two of which are structured to store either one block of the first category, or one block of the second category or a number of blocks of the second category simultaneously.