Article View: sci.crypt
Article #2882Re: Any way to *CREATE* Vcr+ (VCR PLUS) codes??? (please read)
From: Curt Welch
Date: Wed, 06 Jan 1993 17:46
Date: Wed, 06 Jan 1993 17:46
45 lines
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2779 bytes
David Sternlight writes: >Back then, I noticed that two >sources of published codes, the L.A. Times and TV guide occasionally >had different codes for the same program, which suggests other >than a central source. (They weren't typos, and both worked.) oppedahl@panix.com (Carl Oppedahl) writes: >I trust that readers of this group have no trouble figuring out why >this would happen -- right? >The VCR+ people provide programs to the LA Times, and to TV Guide, >that are not identical. That's a good theory, but I doubt it's correct. I've checked hundreds of codes from many different publications and I've never found two different codes that mapped to the same show. Our 6 digit algorithm produces a perfect 1 to 1 mapping of numbers to shows for all 6 digit codes, so there's no way Gemstar could have different programs producing different numbers. Part of the success of the VCR Plus+ system is due to the length of the codes being very short. Gemstar bent over backwards to reduce this as much as possible. This was the key weakness in the code that made it so easy to break. If they allowed multiple PlusCodes to map to the same show (so they could tell who encoded it) then it would make the codes longer. I doubt they did this. Sometimes, the same show will have different numbers because the different guides will be using different channels (which they expect you to deal with using the channel mapping function of the VCR Plus+). But you can see this when you punch in the numbers because it shows you the channel. If you punch in two different numbers, and it seems to map to the same show and same channel, then the difference is probably in the duration. This has been the case every time I've found two different numbers for the same show. It will typically be for shows when strange durations or start times. On guide might use a duration of 1:50 and the other will choose 1:55. /-----------------------------------------------------------------------------\ | Curt Welch - KCW Consulting By 1995, there will be just two kinds | | curt@kcwc.com - NeXTmail please! of professionals: Those who use NeXT,| | (703) 938-4152 FAX (703) 938-5756 and those without Jobs. | \-----------------------------------------------------------------------------/
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Path: arc1-ca.pugleaf.net!sparky!uunet!dtix!oasys!kcwc.com From: curt@kcwc.com (Curt Welch) Newsgroups: sci.crypt Subject: Re: Any way to *CREATE* Vcr+ (VCR PLUS) codes??? (please read) Message-ID: <29329@oasys.dt.navy.mil> Date: 6 Jan 93 17:46:39 GMT References: <1iaa91INNhgr@agate.berkeley.edu> <C0F4nF.7Eu@panix.com> Sender: curt@oasys.dt.navy.mil Reply-To: curt@kcwc.com (Curt Welch) Organization: KCW Consulting Lines: 45