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A recent application of VEIL, the Veil Rights Assertion Mark (VRAM or V-RAM) is a copy-restriction signal that can be used to ask devices to apply DRM technology. This has been seen as analogous to the Broadcast Flag . It is also known as " CGMS-A plus Veil" and "broadcast flag on steroids." There are two versions of VEIL on the market:
The symbols (groups of 4 data bits) transmitted by VEIL-II system are encoded as "PN sequences", sequences of 16 "chips". Groups of 4 chips are encoded in pairs of lines. Each line pair is split to 4 parts, where the luminance is raised or lowered (correspondingly vice versa in the other line). In NTSC, 4 bit symbols are encoded in groups of 8 scan lines. With 224 lines per field this equals 112 bits per field, or 7200 bits per second of broadcast. VEIL-II uses scan lines 34 to 258. The PN stands for "pseudo noise" and signifies the 0.5/0.5 relative frequencies of ones and zeroes. In practice, 20 chips per line are preferred, increasing redundancy and allowing for better error detection. The PN encoding is a form of Spread Spectrum modulation. Stripping the VEIL signal from the video is supposed to be more difficult than tampering with the VBI, therefore VEIL 1 is proposed as a DRM tool. The signal can survive recording to video, and various sorts of digital compression. The detection devices are low-cost and can be used in a range of devices, from toys to cellphones. USE IN TOYS The technology was developed for transmitting data from the video on screen (originally used on '' The Batman '') to a line of Batman toys based on the series, supplying them with information about the series and unlocking their hidden capabilities. {Link without Title} For example:
This technology is used also in other toys. OTHER USES As of December 2005, VEIL was proposed as a DRM tool to counter the Analog Hole , as a technological measure legally enforced by Digital Content Security Act . In this regard, it is a more fine-grained successor of Macrovision . VEIL acts together with CGMS-A signal (" Broadcast Flag ") in the Vertical Blanking Interval , where it is used to encode the Rights Assertion Mark (RAM) signal. The CGMS-A can be stripped too easily from the analog signal, therefore the presence of RAM but absence of CGMS-A will tell the Copy Protection system to deny the copy. {Link without Title} SEE ALSO
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