In 2012, x264 was revolutionary. Previous fansubs used XviD/DivX (AVI containers), which were large and blurry. This encode uses H.264/MPEG-4 AVC. For a dark anime like Blade , where black levels are critical, x264 prevents the "blockiness" seen in older codecs. The result is a file that is roughly 200-300MB per episode but retains the atmospheric darkness of the Madhouse animation.