It looks like you’re referring to a specific for a video release of Prison Break Season 4:
Prison Break Season 4 is a marathon, not a sprint (clocking in at 24 episodes). The release allows you to binge the entire L.A. adventure of "The Company" takedown without hogging 100GB of your storage. Prison Break Season 4 720p BluRay X265 10Bit 2C
Most standard video is encoded in 8-bit, which offers about 16.7 million colors. encoding increases that to over 1 billion colors. It looks like you’re referring to a specific
: Uses High Efficiency Video Coding, which can reduce file sizes by up to 50% compared to older x264/H.264 formats without losing noticeable quality. Color Depth (10-bit) Prison Break Season 4 720p BluRay X265 10Bit 2C
The x265 codec makes this ideal for archival if you are low on hard drive space.