High-Bandwidth Digital Content Protection, also known as
HDCP, is a newer form of Digital Rights Management (DRM) that was designed to control
digital video and audio content. The technology was originally created by Intel
to ensure that digital audio and video travelling across a Digital Video Interface
(DVI) or High-Definition Multimedia Interface (HDMI) would follow the various guidelines
put forth by the Digital Content Protection group.
What Is Required Of An HDCP Capable Device
In order for a product to claim that it is HDCP
capable, it must have a license with Intel's subsidiary company, the Digital Content
Protection group. All makers of HDCP capable devices have to pay various licensing
fees and prove that their devices will not violate any of the policies given to
them under the rules set forth by Digital Content Protection. Furthermore, any product
which obtains a license under Digital Content Protection must agree that should
the HDCP guidelines be broken, the digital video quality from the device will be
reduced or the digital video will not be able to play. Some of the rules currently
stated by the HDCP contract require that such HDCP capable devices are unable to
make any copies of the content which they can play. Furthermore, HDCP capable devices
cannot have any design specifications which may work to defeat any of the HDCP content
protection requirements set forth by the Digital Content Protection group.
HDCP-protected systems may include three types of
devices: sources, sinks, and repeaters. HDCP protects data as it is transmitted
between each of these devices when they are connected via HDMI or other HDCP-protected
digital interfaces. Each device contains one or more HDCP transmitters or receivers,
or it may contain both receivers and transmitters. Sometimes HDCP and HDMI functionality
are combined into a single transmitter or receiver chip.
Source: The source
sends the content to be displayed. Examples include set-top boxes, DVD and Blu-Ray
players, and computer video cards. A source has only an HDCP/HDMI transmitter.
Sink: The sink renders the content for display so it can be viewed.
Examples include TVs and digital projectors. A sink has one or more HDCP/HDMI receivers.[10]
Repeater: A repeater accepts content, decrypts it, then re-encrypts
and retransmits the data. It may perform some signal processing, such as upconverting
video into a higher-resolution format, or splitting out the audio portion of the
signal. Repeaters have both HDMI inputs and outputs. Examples include home theater
audio-visual receivers that separate and amplify the audio signal, while re-transmitting
the video for display on a TV. A repeater could also simply send the input data
stream to multiple outputs for simultaneous display on several screens.