PTP
Picture Transfer Protocol
A standard for transferring media files between two connected devices. Typically, the files are photo (or similar) files and the connection is USB.
A typical use would be transferring photos from a phone over a USB cable.
See: USB
Unlike some other protocols, PTP is designed to allow multiple devices to access the same set of files at the same time, without the risk of files becoming damaged.
For example, consider photo files stored on a phone's internal memory, and that phone connected to a computer. With a protocol such as USB Mass Storage, the portion of internal memory with the photos must be disconnected (in software) from the phone before the computer can access that memory to add or remove photos. Otherwise files could be damaged if both devices attempt to change them at the same time. It isn't possible to disconnect that internal memory if the phone has one pool of internal memory that also stores the software that keeps the phone running (as some phones do.)
PTP solves that problem by carefully managing the connection and access to files, ensuring that files aren't damaged. The drawback is that MTP only allows simple access to certain types of files, whereas other protocols allow access to more files in more parts of memory.
PTP is almost identical to MTP, a related protocol for other types of media.
See: MTP
Last updated Nov 8, 2019 by Rich Brome
Editor in Chief Rich became fascinated with cell phones in 1999, creating mobile web sites for phones with tiny black-and-white displays and obsessing over new phone models. Realizing a need for better info about phones, he started Phone Scoop in 2001, and has been helming the site ever since. Rich has spent two decades researching and covering every detail of the phone industry, traveling the world to tour factories, interview CEOs, and get every last spec and photo Phone Scoop readers have come to expect. As an industry veteran, Rich is a respected voice on phone technology of the past, present, and future.
