Digital media & smartphone: formats, interfaces, management

The main aim of this article is to provide an overview of digital media, their use and management within a smartphone and its environment.

First coined in 1995, the term "smartphone" refers to a class of mobile terminals (multi-purpose mobile computing devices), and more specifically to cell phones. After the development of a few precursors in the late 1990s and early 2000s (Personal Digital Assistant PDA + hybrid phones, cell phones with small screens), the first "modern" models became widespread (Blackberry in 2002, iPhone 1 ^era generation in 2007...).

Since then, the smartphone has become a multifunctional mobile for communicating, sharing and interacting (telephony, messaging, social networks, networked games), getting information (Internet), managing (calculator, contactless payment) and getting around (geolocation, compass, cartography). But it has also become a multimedia mobile for taking photos (photophone) and videos, recording sounds, viewing them, storing them, editing them, sharing them... It has therefore very quickly become an everyday object and a "media center" in a global digital environment. In fact, it's worth noting that smartphone specifications place far more emphasis on "media" parameters than on telephony.

Although this device incorporates increasingly high-performance components and technologies, the use and management of digital media comes up against several difficulties:

• support for multiple media essence formats (audio/fixed image, photo/video) and associated container formats;

• the use of wired and wireless sound and image capture and playback interfaces;

• management of user functions (store, search, edit, etc.).

The three parts of this article provide information on how to overcome these difficulties by :

• specifying the digital media formats that can be supported on a smartphone, both media essence formats (audio/photo/video) as well as their container (file) formats, especially in the Android environment, which is the most widespread operating system;

• specifying the interfaces and their parameters, necessary for managing and using the media and available on the smartphone, both for acquisition (for taking pictures and sounds), restitution (for listening and viewing) and communication (for transferring to and from the outside);

• clarifying the functions specific to digital media management (such as storing – saving, protecting, sorting – classifying – searching, listening – viewing – identifying, editing,...