Riplock is a characteristic of newer computer DVD-ROM drives that slows the drive transfer rate when reading DVD-Video

DVD-Video

DVD-Video is a consumer video format used to store digital video on DVD discs, and is currently the dominant consumer video format in Asia, North America, Europe, and Australia. Discs using the DVD-Video specification require a DVD drive and a MPEG-2 decoder...

 data, typically to 2x-4x on drives that otherwise (as of mid-2005) could read at 8x or 16x. This restriction reduces the amount of noise when the drive is playing a DVD by providing the lowest rotational speed that allows for adequate data transfer from the DVD to the computer. This slow speed and low data rate makes it less convenient to rip

Ripping

Ripping is the process of copying audio or video content to a hard disk, typically from removable media. The word is used to refer to all forms of media. Despite the name, neither the media nor the data is damaged after extraction....

large DVD video collections to a computer. On some riplock-equipped drives, riplock can be removed by firmware reflashing (referred to as "increase read speed," "read speed patch," or "riplock patch"). It can also be disabled on some drives by pressing the eject button for three seconds without any disc inserted.

LiteON calls the riplock feature SMART-X.