Media decoding control with hardware-protected digital rights management

Abstract

Innovations in the field of hardware protected digital rights management ("DRM") systems are presented. For example, a hardware protected DRM system includes trusted and untrusted layers. In the untrusted layer, the control module receives source media data including encrypted media data. The control module handles metadata about the media data. Metadata that may be exposed by modules in trusted layers is not opaque within untrusted layers. In the trusted layer, by using the key data, the module decrypts the encrypted media data, which may be the encrypted media data from the source media data or its transformed encrypted version. Modules in the trusted layer decode the decrypted media data. A host decoder in the untrusted layer uses metadata to manage at least some aspects of decoding, rendering and display in the trusted layer without exposing decrypted media data or key data within the untrusted layer.

Description

Background technique [0001] Playback of digital media data has become a common feature on devices such as smart phones, tablet computers, personal computers, game consoles, and set-top boxes. As distribution and playback of digital media data has become more common, various digital rights management ("DRM") systems have been developed to protect media data from unauthorized copying, distribution and playback. Typically, DRM systems use encryption to protect media data so that only authorized parties can playback it. The authorized party can then use the DRM system to decrypt the media data for playback. Before encryption, the media data may be compressed or encoded to reduce the bit rate of the media data. If so, the media data is decompressed or decoded after decryption but before playback. [0002] Typically, the focus of a DRM system is the operations that occur at the playback device, as this is where decrypted media data may be most vulnerable. In some DRM systems, at...

AI Technical Summary

Problems solved by technology

Although hardware-protected DRM systems tend to provide better security guarantees than software-protected DRM systems, they can be inflexible

In particular, the flexibility of software-controlled media decoding is lost or hindered in hardware-protected DRM systems

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