Specifications on CGMS-A for 525 P Output from DVD-Video Player

This document describes the CGMS-A specification for the 525P output signal from a DVD-Video player. This specification is derived from 2 specifications: EIAJ CPR-1204-1 and IEC61880.
In order to provide more information on these specifications, certain members of Ad Hoc 2 of Working Group 9 of the DVD forum have provided this explanation of CGMS-A for the 525P signal.
EIAJ CPR-1204-1 specifies the wave form for the vertical interval of the 525P signal to transfer the video related information (excluding CGMS-A copy control information code).
IEC61880 defines the bit assignment for CGMS-A for the 525i signal.
But this assignment is also applied for 525P output from a DVD-Video player.
IEC 61880 is an international standard and is available in English.
EIAJ CPR-1204-1 is a technical report of the Electric Industries Association of Japan, entitled "Transfer Method of Video ID information using Vertical Blanking Interval(525P System)". This document is written in Japanese.
These two specifications are open standards, so that anyone can access and use them. It is anticipated that these two specifications will be merged together and will become an IEC specification.
At that time, this specification will be referred to as the CGMS-A specification for the 525P signal.

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1, The wave form of CGMS-A for 525P signal
EIAJ-CPR-1204-1 defines the wave form as follows.
The identification signal consists of a reference signal of 70% of white peak level and a 20-bit digital data signal indicated by 0% or 70% of white peak level in the 41st horizontal line of the video blanking interval. The 20-bit digital data signal is coded and transferred as an identification signal for video related information.
Clock frequency fc:
fC =fHx 33 = 1.0385MHz
where
fH is horizontal scanning frequency.
Figure 1 shows the identification signal wave form
The cumulative timing error for each bit, measured from the rising edge of the reference bit, should be within 0.22s.

2, Bit and code assignment of the identification signal
IEC 61880 defines the bit and code assignment of the identification signal.
In these specifications ,only CGMS-A related parts are referred to for 525P signal.

3, References
EIAJ CPR-1204-1: 1998, Transfer Method of Video ID information using Vertical Blanking Interval (525P System)

IEC 61880: 1998, Video systems (525/60) - Video and accompanied data using the vertical blanking interval - Analogue interface

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