Image Constraint Token

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Image Constraint Token or 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 an AACS-enabled player is not connected to a HDCP-compliant display (such as when a display is connected to the player through analog connections) 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 the first generation HDTVs did not come with 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.

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.