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Can DVDs Kill DVD Players?
aidanpryde asks: "In the weirdest situation I've ever seen. My DVD player died on Saturday while watching the episodes of a favorite sci-fi series. I was watching disk 5 with my wife and noticed that it was getting jumpy. I took the disk out to see if it was dirty or scratched, but seeing nothing, we put the disk back in. Now the DVD player won't read anything, not the Season 5 disk, none of our other disks...nothing! So, we take the DVD player as a loss. Hardware failure happen all of the time, right? So I go downstairs with my wife on another day and try it on her DVD player in her computer. We get through one episode of the disk and it starts to jump again. We take it out, try another disk and sure enough -- nothing works. Has anyone ever run into DVD's that kill DVD players? Is there any way that I can get compensation for my dead DVD players? Is there any ideas as to why this has happened. Can I download firmware updates for the computer drive that may fix the problem?"
Heh.. You probably could actually get some money for a magic DVD that kills DVD players... There are a lot of malicious people out there...
If the DVD is warped, no longer very flat, it might (?) hit the lens. ???
DVD players are meant to play DVD's and have specialized DSP's that don't run ridiculously hot like a Prescott. The idea that some DVD's are "just too much for your DVD player to handle" is slightly ridiculous.
Moderation is to make the discussions more interesting. It's not a meritocracy. You're not a 'cooler' person because you have +1. Nobody cares what your real name is. etc. etc.
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The other day I was driving around in my car and it stopped running. While it was being repaired I was driving another car that stopped running too! I'm pretty sure that I'm the cause of it.
See where I'm going with this?
Nobody has suggested the extremely obvious possibility: both DVD drives failed. Perhaps they were going to fail for some time but they didn't start showing problems until you played a dual-layer DVD.
Its highly unlikely anything about that disc could "damage" your DVD drives. Its far more likely that both drives were near their failure point and failed by coincidence.
I've also used Linux 2.6 kernel builds to test overheating issues on my laptop (Athlon 2200XP). I've had other overheating problems with other, less-strenuous apps; this was just one test. Turning it in for a warrenty repair fixed the problem.
I've also had DVD's wreak havoc on my Apex DVD player. The first time I tried X-men2 and Planet of the Apes it choked on the menu introduction animation. My sisters have a habit of leaving it running 24/7, so turning it off for an hour or two and trying again usually works.
Its supposed to have the ability to play back MP3s, but every time I tried, it stutters in playback, like its having a problem decoding the data fast enough i.e. underpowered. Perhaps the MP3s use the CPU and the DVD uses DSP/CPU combo; a problem with one could lead to a problem in the other.
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That is a damn good idea! - the best and most useful comment on this topic. Try it, and tell us what happens.
Maybe, but the record companies have promoted this "music" as being very good, when it is, in fact, trash.
The root of the problem is the fact that you're not (normally) allowed to return music after having listened to it. How are you supposed to know if it's any good if you can't listen to it beforehand?
If I go to Wal-Mart and buy a DVD player, or a stereo, or a power tool, I can bring it home, try it out, decide I don't like it, and put it back in the box and return it for a full refund. Most stores will allow this on most items. But not, curiously, for music, even though the act of playing a CD does not damage the disc in any way, and it can be re-shrinkwrapped and sold again, provided it wasn't scratched or mishandled.
You have an apex dvd player or similar cheap comsumer electronic junk. All I can say is what did you expect?
Last time I checked, ALL DVD players are cheap consumer-grade junk these days. Even the "name-brand" players are made in the same Chinese factories that the cheap "no-name" players are.
Therefore, I see this as a pretty useless comment. It's not like someone buying a Yugo, instead of a Honda or Toyota, and then complaining it breaks down too much. There isn't much choice with consumer electronics.
CD players aren't as smart as DVD players. The data on a CD is just unencrypted PCM audio. 16 bits per sample, 2 channels, 44100 samples a second. But back in the day when CDs were invented, nobody thought it was important to be able to lock out competitors from manufacturing compatible media and equipment. Indeed, the specification was published -- in a certain volume with a rather fetching scarlet cover, the title of which escapes me -- specifically in order to allow everyone to be able to make CDs and players. Yes, even Fred in the Shed, if he had a particularly-well-equipped shed.
The bad news is that the pits and lands do not correspond directly to zeros and ones, but the good news is that it's "just" "simple" cross-interleaved Reeds code, for error correction, and if you are supremely foolha^H^H^H^H^H^Hconfident, you can just parse the "data" bits from the "parity" bits and feed them into your DACs. But it's not hard to build a simple logic matrix that does the error detection and correction.
CD-ROM uses an ingenious modification, where some of the error-proofing bits are replaced by addressing bits. This gives 2048-byte sectors and also has the advantage that the error-correction will be so shot to pieces, that any decent decoder will just spit out all zeros -- which will sound like silence. (Don't attempt to verify this using headphones, since a badly-implemented decoder could produce anything from DC to full-volume static).
For DVD, other concerns (like the movie studios making as much money as possible whether or not it might be morally justifiable) prevailed over not treating the people who pay your wages like shit. So while the disc itself is based physically on the original HDCD specification, the data is unnecessarily munged. (For instance, the audio/video data on a movie DVD is encrypted; although the rightful owner of a DVD is automatically entitled to decrypt it, by virtue of ownership, and may use reasonable force in pursuit of that right, so it serves fuck-all purpose except making life awkward for the person in the street.) And it's possible that there might be the ability to upgrade firmware by having a certain named file on the DVD, though the details would vary from one make of machine to another. One would hope that a sanity-check would be performed on the data first, and then (and only then) would the firmware be upgraded -- ideally, also depending upon some deliberate action by the user.
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