sentences:  Until the conversion to digital projection began to render 35mm film less cost effective, a majority of release prints for major studio films were created with all three digital tracks – Dolby Digital, DTS and Sony's SDDS (each digital track uses different film geography so all three, as well as the analog track, can coexist on one print).Out of the three competing formats, SDDS was the only format not to have a corresponding home-theater version, and Sony ceased production of new units in the early 2000s.The format carries up to 8 channels of Dynamic Digital Sound (DDS) encoded using Sony's ATRAC codec with a compression ratio of about 5