Slashdot Mirror
Solutions to the Frustrations of Video?
Re-Torque asks: "In our organizations, interviews with perpetrators of crime (child abuse, rape, etc), and with victims, are conducted by expert interviewers and are recorded on videotape or DVD (with back ups). These recordings are legal records. They are archival records, but they are also used in the courts and in other aspects of the legal process.
We have encountered problems with newer VCRs and DVD recorders. As long as the tape or DVD is played back on the same machine, there is no degradation of audio and video quality. However, when played back on any other machine, the quality of the recording is substantially degraded. We have been told that this is to frustrate illegal copying, but in our case, it frustrates the legal process. In your experience, is the problem in fact one of design of the machines or are we doing something wrong (i.e., some settings we should change before recording)? Are there any machines available that are not crippled in this way? Or are there other strategies we might employ to resolve this problem?"
I've had this problem with VCRs in the past, recording a show on one player, and then playing it on another would usually yield poor results. Or sometimes one movie I had bought would play fine in one player, but would be very bad quality in another. I assumed it was due to differences in read head alignment or something. On the other hand, I don't know how this could happen with DVDs. Because everything is digital, the output should be the same no matter which player/recorder you use. I've never experienced this problem with DVDs, even with home movies that were recorded onto DVD, they play fine in all the players I've tried them in.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
Let me be the first (or somewhere close) to say that it's high time the legal system finally saw some of the ill effects of 'protecting' hollywood.
-Tim Louden
In progressive JPEG, first the low frequencies are stored, and then the high frequencies are stored. This way, you get a blurred preview image before the rest of the data fills in the detail. The consumer electronics-Hollywood complex could make DVD recorders work the same way: encrypt the high frequencies so that any other player model won't be able to play the copy at full quality, discouraging people from using DVD video recorders to record TV and make counterfeit season box sets.
Why not display the video using a PC with a video card that has composite or S-video output? You should be able to hook up to any modern TV or projector. You could encode the video in whatever format you want: lossless DV, Ogg Theora, XviD, even WMV if you are really sadistic. You could store it on whatever medium you want: DVD, a hard disk, a NAS, CD, usb flash drives, whatever. Backups should be easy.
------ Take away the right to say fuck and you take away the right to say fuck the government.
yes, there are uncrippled machines that can do what you want (and then some). you probably have one sitting on your desk
.wmv files if you intend the video to be played back on windows machines). if you've installed something like VLC on the playback machines, you can use more interesting codecs like h264 and still achieve quite impressive playback quality at much lower bitrates.
3 5618216/sr=8-1/qid=1156903037/ref=pd_bbs_1/104-273 5593-2181510?ie=UTF8)
if you're running under linux, you've got a couple options. kino (http://www.kinodv.org/ will allow you to capture live raw video (plus sound) from a standard dv camera with an ilink (aka 1394a) connection. it takes a little effort to get setup, but it's worth it. you'll then want to use ffmpeg to re-encode the files so that they're less huge and then save the encoded version.
if you have analog cameras, a $50 capture card (we use ati's all-in-wonder) can act as a frame grabber --- it may take a little finagling to get the sound working, but once it's all hooked up you should be good to go. use xawtv to preview and make sure that everything is behaving as expected, then use ffmpeg to capture the video. make sure you encode at fairly high bit rate and be careful about what combinations of codec and containers you choose (in particular, you probably want to stick to msmpeg4v2 encoded
there are ways to do similar things in windows, although i have much less experience doing so and tend to use developers tools (like graphedit) to put together the directshow filters that will capture video and sound from some source, encode, mux, and then output the file. i'm sure that there are pieces of software out there that can do this. if you have access to some it people, writing your own should be fairly easy (there's a handy book on the subject here: http://www.amazon.com/Programming-Microsoft/dp/07
if you're not inclined to build your own solution, virtualdub http://www.virtualdub.org/ may be able to help you. i haven't used it myself, but it's a pretty widely used app.
the one thing to bear in mind with all these proposed solutions is that you're going to want to make sure you've got fairly big and fast disks and quite a lot of space free. you're also going to want to make sure you've got a reliable backup strategy in place since you no longer have the luxury of the original tapes. if you have any other questions, feel free to email me: (my slashdot user name) 'at' yahoo(dot com).
Any DVD recorder that can't write stuff that can be played back well with normal working players is faulty.
Whatever they tell you, it is faulty. Send it back and get a refund or working replacement.
Given you are likely to know many friendly lawyers, maybe you could hint that various sorts of unpleasant legal action might be taken if they don't do the right thing...
Unauthorized footage is prohibited. Think of the goddam starving grips, script writers, and boom operators who you are putting out into the street because you are undercutting their livelihood with your "recordings" for "legal purposes." What a crock. If you really are "law enforcement" you should do things the right way and hire a Hollywood studio to record these things for you. Anything else is the same as shoplifting.
Seriously, you are SOL. There are definitely ways to beat this kind of thing, but you will be breaking the law and/or causing others to break the law simply by inquiring. The operators of Slashdot may even get a nice visit from the FBI if anyone posts methods for how to defeat these copy protection measures.
Welcome to the future, where due process is no obstacle to protecting media companies' profits.
Our intelligent designer has never created an animal that we couldn't improve by strapping a bomb to it.
You really shouldn't be seeing issues like this with user-created DVDs.
So far as VCR's go, there's a lot of moving parts in there even for "simple" consumer-level devices. Regular maintenance is essential, especially on high-use equipment. The most common cause of recording/playback/portability problems is due to the back-tension rollers. These are rubber-coated wheels which help to hold the video tape against the head drum to ensure proper reading/writing from/to the oxide layer. These eventually get a smooth sheen on them due to wear and oxide stripping from the tape and thus cause slippage and irregular transport of the tape and glitches in the signal. They can usually be fixed-up on the cheap by removing them, putting them on a machined screw on a dril and using fine-grade sandpaper just enough to remove the sheen. Clean them with alcohol to remove debris and reinsert in VCR. There may also need to be adjustment to the back tension spring on the arm which holds the back tension wheel, but this is usually better left alone. Other maintenance activites also involve cleaning the audio/tracking head and head drums (the heads themselves, actually) to remove oxide and other gunk buildups to ensure proper contact with the tape, and also occasionaly replacing the rubber drive and loading belts - particularly if the unit has been sitting idle for a while. Dai-ichi make a large range of belts for many models, which we get from WES Electronics - far cheaper than "brand" name belts.
If your budgets are anything like police budgets in Aus then you're probably limited to consumer-level devices. You can't go past Samsung VCR's, especially get ones with the "Dub" or "Edit mode" switches as these tend to avoid the Macrovision-style copy corruption (err, protection) techniques employed in a lot of other VCRs. The seems to be getting even more prevalent, even with everyone allegedly using DVDs now or pirating movies from the net.