Self-protecting digital content

A media player comprising:

• a memory;
• a media interface;
• and
• a processor to receive data comprising both digital content and data processing instructions corresponding to the digital content, the received data being received from a source external to the media player via the media interface, the received data being storable in the memory of the media player, the processor being further configured to execute the data processing instructions from the memory by using a computer language interpreter of the media player, the data processing instructions, when executed by the computer language interpreter, configuring the computer language interpreter to:
• interrogate a playback environment of the media player, the data processing instructions further configured to perform a security check that interrogates the playback environment of the media player and to verify at least one of:
• a media player device identifier, including at least one of a player serial number, specific subscriber information, a player model, or a player software version, and a user identity, including at least one of a user name, geographical region, email address, or a web address, the data processing instructions further configured to reduce output quality if a result of the interrogation of the playback environment is uncertain;
• query one or more countermeasure routines stored in the memory of the media player, the countermeasure routines collectively mitigating security weaknesses in multiple models of the media player, the countermeasure routines including cryptographic data and executable instructions for performing cryptographic operations, the computer language interpreter not having access to the memory in which the countermeasure routines are stored;
• and
• request execution of a countermeasure routine by the computer language interpreter.