Image Constraint Token

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Image Constraint Token (ICT) is a protocol flag that causes downsampling of high-definition video content on Blu-ray and HD DVD to slightly-better-than-DVD quality video. It is part of the Advanced Access Content System, the Digital Rights Management system used in the next-generation of optical discs.

[edit] Operation

When using an AACS-enabled player, all the components in the display chain must support HDCP, including the display panel. If any components in the display chain do not support HDCP (such as a display connected to the player through analog connections like Component, Composite or S-Video) and the ICT flag is enabled, the player automatically reduces the high-definition video to the resolution of 960x540 pixels before outputting it. Some HDTV early adopters dislike the ICT flag because initial HDTVs did not incorporate HDCP support and thus, if this was activated, these people would not be able to enjoy high-definition video off of such discs. Hollywood has reportedly agreed to not activate this flag for discs released in either of the two formats until 2012.

It's also worth noting that the vast majority of Xbox 360 consoles lack a HDMI port, and thus the HD DVD add-on is also subject to image downgrading, once ICT is enabled. The Xbox 360 Elite console (announced March 27, 2007) does however feature HDMI. [1]

The Image Constraint Token applies on a per disc basis, so that one movie title could have it enabled while another from a different studio could have it disabled. It impacts video only, and has no effect on audio signal quality. Discs with ICT enabled will have it marked on the outside of package, allowing consumers to see if the specific disc contains the set flag.