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Hardware

Could CDRW Disks Replace Videotapes? 360

NewtonsLaw asks: "I'm in the process of building a TiVo-like PC that uses off-the-shelf technology to implement video timeshift, MPEG recording, MP3 recording, etc along with Net-radio functionality. Over the past two months I've effectively replaced VHS video tapes with CDRW disks. Once a program has been captured on the PC in (S)VCD MPEG format, I can either watch it by playing back the recorded file or dump it onto a CDRW and watch it on my DVD player, before blanking the disk and returning it to the 'empty' pile. What I've noticed is that most of the CDRWs I've tried only last about 30-40 rewrites before they start showing significant data dropouts (almost always at the start of a recording). Since disks in (S)VCD format don't carry the same level of error-checking/correction as disks written in regular data format, such dropouts are more noticeable than they would otherwise be (of course the up-side is that you get to store 805MB on a 700MB CDR/RW without overburn). What I want to know is -- how many rewrites do most people expect from their CDRW media? I seem to recall seeing a figure of a thousand rewrite cycles being touted by some manufacturers. Is this realistic? Thirty rewrites makes a $2.50 RW disk an economic medium for this purpose but it seems a hell of a long way short of 1,000."

"I've tried CDRW disks from several manufacturers and they're being used in a new Sony CDRW drive which seems to function just fine. I've also encountered a slightly shorter lifetime for CDRW media when used for (S)VCD disks and written by a slightly older HP CDR/RW drive.

And before anyone asks 'Why don't you just play directly from the HD?', I should point out that I have to share the TV gear in this house with the rest of the family so it's just easier to burn their stuff to disk and let them use the DVD player than to fight over access to the TiVo-clone."

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Could CDRW Disks Replace Videotapes?

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  • Q: Could CDRW Disks Replace Videotapes?

    A:Over the past two months I've effectively replaced VHS video tapes with CDRW disks.

    Sounds like "Yes!" to me!
    • True dat but he is wondering in a more general case. Also, I want to note that video tapes will hardly be replaced in what i am understanding replaced to mean. Eventually, the product may no longer be marketable, but going by example casettes/record players etc. still work and are utilised.

      Thesis: If it aint broke dont fix it.
      Antithesis: Add functionality to improve quality or ease-of-use even if it works fine.
      Synthesis: Up to the consumer and their wallets.
    • Same here. I gave away my VCR that I paid over $300 some years ago. I also gave a away a cheaper one that sat underneath it. Video tape looks horrible compared to a good VCD or DivX. I don't bother with CDRW. CDRs are so cheap I just use them. If I don't want it anymore I'm only out thirty cents or so.
  • I heard around "100" (Score:5, Informative)

    by delus10n0 ( 524126 ) on Wednesday October 23, 2002 @04:34PM (#4516842)
    If I remember correctly, the CD-RW blanks I have at home (14x compatable) say they are "guaranteed" for 100 re-writes.

    Also, what speed are you burning on these CD-RW's at? Maybe you should try lowering the recording speed and seeing if you still get the drop outs.
    • > If I remember correctly, the CD-RW blanks I have at home (14x compatable) say they are "guaranteed" for 100 re-writes.

      Off the top of my head - that's a hell of a lot better than VHS, so I'd say the answer's "Yes".

      (If you're trying to store 120 minutes of video on a CD-RW, you're going to have to compress it pretty heavily, but on the other hand, you're only competing with VHS quality, so you can probably sacrifice quality for compression.

      If I were designing the thing, I'd go with VCD quality - less than 120 minutes per disc, but if your shows are 22, 44, or 66 minutes long (30/60/90 minutes, with the ads cut out), that's a win for the CDRW.

      • by Sancho ( 17056 ) on Wednesday October 23, 2002 @06:03PM (#4517656) Homepage
        I don't know about VCD. To me, the quality just isn't there compared to a well-kept VCR. SVCD can compete with it's higher (and variable) bitrate, but then you suffer from 35minutes of video (for top quality) per disc.
        If you get a DVD player that can play out of spec (S)VCDs, this can sort of change. You can up the bitrate of VCDs, and/or make them VBR to increase qulaity. You can also check out the CVD standard, which is 352x480, VBR, mpeg-2. It's a real standard, and it's only a bit off from SVCD. You save a bit ont he bits (giving you a bit more time per disc) and better yet, the valid CVD streams are completely compatible with the DVD spec, meaning if you ever get a DVD burner, the same streams will can be burned as a DVD-Video.
    • by Eric Green ( 627 ) on Wednesday October 23, 2002 @07:13PM (#4518197) Homepage
      I've done some work with DVD/RAM media under the UDF filesystem. After about 40 writes, typical DVD/RAM media starts building up a hefty defects list. After about 100 writes, the defects list gets long enough that the media becomes basically unwritable. I am not impressed by the current state of optical disk technology. Given that CD-RW is an early primitive version of what eventually became DVD/RAM, it does not surprise if "around 100" is the correct answer, though I wouldn't re-use a piece of media more than 40 times under any circumstances.
    • hey 100 is *sooo* much better then the first generation CD-RW's (which I was foolish enough to buy). They lasted between 2 and 4 burns, and the way you found out they were broken was by loosing your data. Also those first disks seemed to degrade over time, they would verify correctly a few minutes after the burn, but then after a few days/weeks they were worthless and full of errors (with no abuse).

      That scared me off using them for 3 or 4 years, but I recently started using them again and they dont seem to have these problems now.

  • CD-RW (Score:3, Insightful)

    by jlechem ( 613317 ) on Wednesday October 23, 2002 @04:34PM (#4516849) Homepage Journal
    My personal experience is that a nice quality video doesn't fit on a 700MB cd-rw. Not unless there is significant amount of compression and then the quality suffers. That is my only bitch, IMO CD-RW's are easy to create, play, and store. Not quite as convienant as tape, but in the future it very well could be!
    • Re:CD-RW (Score:3, Insightful)

      by FireMotion ( 227702 )
      Fit?

      On the other hand...

      A lot of CD's fit in the same physical space it would take to store a VHS cassette in. And there are "juke boxes" for audio cd's, a juke box for video CD's (CD/CDRW/DVD etc) sounds more likely than one for VHS cassettes.
    • Re:CD-RW (Score:2, Insightful)

      by monadicIO ( 602882 )
      nice quality video doesn't fit on a 700MB cd-rw
      This has me wondering - is the quality of video even on a new VHS tape good enough that it might significantly deteriorate when copied onto cd-rws? Of course, all of us law-abiding people are talking about movie^H^H^H^H^H home videos, aren't we?!
      • Re:CD-RW (Score:2, Informative)

        by blitziod ( 591194 )
        cd r's can hold a video tape about the same quaility of a VHS tape. The quality is also slightly lower than the resolution on most TV's. video cd format or VCD is around 250 lines of resolution. The average TV displays 300. VHS tapes are around 250 too.
        • Re:CD-RW (Score:3, Informative)

          by benwaggoner ( 513209 )
          analog video "lines" and lines of digital resolution are two different things, alas.

          When someone talks about lines of VHS, they're talking about how many discreet changes in amplitude you'll be able to measure on a horizontal line. And when digital video talks about lines, it's normally how many pixels high the video is.

          And due to Nyquist, we know the sampling rate required to record a given frequncy is twice the frequency.

          So, MPEG-1 NTSC VCD at 352 pixels wide could reproduce a frequency of 176 changes over the horizontal width of the video. So, if VHS is 250 lines, it's actually better on that measure than VCD.

          Of course, VHS is plauged by horrible analog noise to the point where I can't watch it, while VCD, although low resolution, shouldn't have any noise at all. There will be some artifacts at VCD data rates, of course.
      • VHS source (Score:3, Informative)

        by benwaggoner ( 513209 )
        VHS has a ton of analog noise. This means that you'll need to encode the digital copy at a substantially higher data rate to get the same effective quality, and you'll have a pretty low ceiling on maximum quality.

        The difference between even S-VHS and VHS is huge.

        So, grabbing off DVD or straight from a high-bitrate PVR would be quite a bit better. And if you have to go through analog, make sure you're capturing via S-Video instead of composite. Otherwise areas of saturated color will get that annoying cross-hatching effect. It's isn't so noticible on TV, but man is it obvious on a computer monitor!
    • Re:CD-RW (Score:3, Interesting)

      by Camulus ( 578128 )
      You are correct that the 700MB limit sucks. However, I have had some good experiances with an Apex 3 disk model. That way you can split a Replay Tv'ed mini-series into three svcd disks and take them with you to a friends house to watch and there is just a slight pause between the disks. It worked well for me.
    • Re:CD-RW (Score:2, Informative)

      by forevermore ( 582201 )
      My personal experience is that a nice quality video doesn't fit on a 700MB cd-rw.

      I've been encoding svcd's of my dvd's for a couple of years now (long story short, macrovision + tv/vcr combo does NOT work) and have come to the conclusion that you can put 60 minutes MAX onto an svcd (multipass vbr, 192 or 160 audio) before the video quality degrades to that of a standard VCD. Still, it's cheaper than video tape and doesn't degrade over time.

    • Units nitpicking (Score:2, Insightful)

      by Anonymous Coward
      Nice quality video isn't achievable below some bitrate. 700 MB isn't a bitrate, it's a bitcount. Your claim would only make sense if you phrased it as "more than X minutes of nice quality video doesn't fit on a 700MB cd-rw". You didn't give a value of X and you got score 4 insightful??
    • Re:CD-RW (Score:2, Interesting)

      by killosdnbar ( 530347 )
      If you ever watch a VCR tape and a VCD on a low-end TV (no HD now) you will probably be happier with the VCD quality. I even drop the VCD quality to about half the bit rate and I still can't see the difference on the crappy TV, except that VCDs don't bounce around.

      Of course my computer monitor is a completely different story.
    • Re:CD-RW (Score:3, Interesting)

      I have a divx version of "Legally Blonde" (yes, I own a copy of the dvd) which is almost indistinguishable from the dvd. That divx encode is stored on a bright pink 700 Meg CDR.

      Now before you go around saying that quality is subjective, and I don't know what to look for, I'd like to mention that I work in the video capture and compression industry (coding drivers for various products, including mpeg-2 [en|de]coders). I'm familiar and, generally, fairly sensitised to the various artifacts resulting from DCT and wavelet compression, interlaced video, scaling, etc.

      It sounds like you are used to seeing poor quality encodes. There is an art to getting the best quality out of the bandwidth allocated.

      -SpeedBump

      PS: I should concede, though, that the "Legally Blonde" divx that I have probably benefitted from the ability to do multi-pass encoding.
  • Dead CDRW's (Score:3, Informative)

    by FireMotion ( 227702 ) on Wednesday October 23, 2002 @04:35PM (#4516859) Homepage
    Even with normal data, the samsung burner, made the CDRWs I used lose data already after 4-5 burns. I think for permanent storage, normal CDr's are good, but I wouldn't trust CDRWs too much with any of my computer data or audio/video.
  • # of rewrites... (Score:5, Informative)

    by dallask ( 320655 ) <codeninja@gmail.cERDOSom minus math_god> on Wednesday October 23, 2002 @04:36PM (#4516863) Homepage
    Typicly I will reuse my CDRW disks arround 10 -> 15 time, but im storeing my programs, mp3 backups, and web dev work... so once its backed up to my satisfaction... I stop...

    Personaly I think that to acheve 30 -40 rewrites to a VCD disk with no real loss in quality beats the shit out of a VCR which you only really get 4-5 rewrites out of before you start noticeing quality issues...

    Keep up the good work, and keep us informed as to when we can buy the set top version of your system :)
  • by Bonker ( 243350 ) on Wednesday October 23, 2002 @04:36PM (#4516866)
    ...From various places. I have a low-end P3550 and a video out-card hooked into my home entertainment system. CDR and CDRW has all but replaced VHS for me.
  • by Anonymous Coward on Wednesday October 23, 2002 @04:37PM (#4516871)
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    | ooo .o |
    | o . |
    | ooo . |
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  • then ONE, NO REWRITES. If it is just temp storage I've been able to use a disk like 40-50 times for passive data storage without incident. I do keep the disks in a dark place and DO NOT EXPOSE them to sunlight. I seriously doubt the veracity of using a cdrw 1000 times. Not that I doubt your word, but the vendor hype :)
  • Once will do (Score:3, Insightful)

    by f97tosc ( 578893 ) on Wednesday October 23, 2002 @04:38PM (#4516890)
    There are basically two reasons to save:

    1 You don't have the time to watch while the program is being broadcast. Save it on the TIVO hard drive and see it later that night or two days after or whatever. Then delete.

    2 You have a genuine interest in the program and want to save it for the future. Then save it on a disc, and don't overwrite it.

    Tor
    • Re:Once will do (Score:3, Insightful)

      by gid ( 5195 )
      There's tons of legit reasons for CDRW's. What if I want to save a friends episode, but only until my sister finally comes over, maybe months later to watch it. What if I want to save bunch of simpsons episodes to watch during thanksgiving. Or bigger yet, what if I want to record friends and then take it over to my girlfriend's place?

      There's many reasons to save something for the medium term.

      Why do people insist on trying to convince users that don't need something that they explicitly asked for? And have perfectly legit reasons to request the said item. Fully assess the situation first next time, and then make suggestions.
      • Because, in general, users are misled. Just because a few actually know what they are talking about doesn't mean that the majority does too. As a long-time employee of a Help Desk, I see new evidence of this every day.

        As one of the Men in Black said, "A person can be smart, but people are stupid." Usually you won't have any trouble after explaining why you need it, and they are only trying to save you trouble.
    • by billstewart ( 78916 ) on Wednesday October 23, 2002 @05:09PM (#4517155) Journal
      I wasn't sure if the poster was using TiVO or just using a capture card in his PC (my guess was the latter), but hard disks are not only faster and more useful than CD-RW, they're cheaper. Typical IDE prices are $80 for 80GB, which is $1.00 per GB, or $0.70 per 700MB CD-equivalent. (I just paid $10 for 10 CD-RWs at Fry's last week, so this is slightly cheaper.) Plus you don't need to worry about whether the video exactly fits on one disk. And if you're burning it on a disk, CD-Rs are about $0.10-0.15 for cheap stuff.

      The one exception I can see to this is if you're using the CD as a data transport mechanism, between your PC in the office with the fast data connection and your DVD player in the living room.

  • Perhaps. (Score:5, Insightful)

    by serial frame ( 236591 ) on Wednesday October 23, 2002 @04:40PM (#4516907)
    One of the small-town grocery stores nearby actually sells CD-Rs and CD-RWs at pretty decent prices, and place them next to the blank VHS tapes in the store. Seeing as to how they're becoming more ubiquitous, and devices like the Terapin VCD Recorder (at http://www.thinkgeek.com/electronics/video/57a6/ [thinkgeek.com]) are starting to appear, perhaps CD-RWs could give VHS a run for its money, with comparable video and audio quality, as well as interoperability with a computer. For instance, you just missed Everybody Loves Raymond, so you hit KaZaA and somebody uploaded a VCD for you. So yeah, they've got their merits.
  • I find that the video quality of MPEG-1/VCD to be too low for enjoyment. Perhaps if you could reimplement this with DVD-RAM/DIVX (with one of those new DivX capable DVD-players, e.g. the Kiss DP-450 [yahoo.com], then we'd be talkin.
  • MPEG? (Score:2, Insightful)

    by Lxy ( 80823 )
    Can MPEG really replace VHS? I know, VHS is pretty crappy too, but MPEG seems lossier than VHS.

    I use VCDs quite often, so I'm not dissing MPEG format by any means. I just don't see the attraction of replacing magnetic tape with a lossy format.

    The real solution is cheap DVD-RW.
    • From what I've seen, the quality of the MPEG has a lot to do with specific settings and filters. I've seen some *really bad* MPEGs of, say, Invader Zim floating around the net, and then I've seen some really good [dapcentral.org] ones. (I mean image quality, feel free to have your own opinion of the content, but don't waste our time ranting about it here).
    • You don't want to replace VHS with a lossy format, so you want to use DVDs?

      You do know DVDs are, well, lossy, yes? You could just stream raw vidcaps onto one, but you'd struggle to fit an hour of broadcast video onto a single DVD side.

      (Of course, VHS is also lossy, since it effectively discards most of the horizontal resolution)
  • by Overt Coward ( 19347 ) on Wednesday October 23, 2002 @04:41PM (#4516921) Homepage
    Figure $5 for a pack of 50, so $0.10 each -- you can't re-record on them, but it shouldn't cost you more than CD-RWs that start failig at 15 uses or so. Plus, this way you have the ability to create instant archives of your favorite shows, or just discard the used disks.
    • by klevin ( 11545 ) on Wednesday October 23, 2002 @06:16PM (#4517782) Homepage Journal
      Perhaps he wants to keep form tossing a CD-R into the landfill every time he burns a [S]VCD. If he's getting 30-40 burns per CDRW before tossing it, that's 29-39 fewer disks of plastic, aluminum and die that end up on the trash heap.

      This way, if his family member (who he's burning the shows for) wants a "permanent" archive, he can still reburn to a CDR and put the CDRW back on the blank stack.

      What I want to know is which DVD player he's using to view the [S]VCD's. I recently bought a GoVideo DVD+VCR combo for my folks, and out of curiousity, tried burning some SVCD's & VCD's and playing them. I'll have to take GoVideo/SonicBlue at their word that it will play "commercially produced" [S]VCDs, as it sure couldn't play the ones I burned to CDRs.
  • no (Score:4, Insightful)

    by prichardson ( 603676 ) on Wednesday October 23, 2002 @04:42PM (#4516923) Journal
    The CDR will never replace vidoetapes for the same reason HDTV is only just starting to bloom and cassette tapes were EVER on the market.

    People don't care about quality! If people cared about quality Microsoft would be out of business, Airlines would have decalred bankupcy years ago, and NO ONE would eat fast food.

    Unfortuately people care about how little effort they have to excert to get something done. People don't want to deal with CD-R's because, despite an overall decrease in effort required, short term effects are minimal.

    On a side note: CDRs would be a great alternative to video tapes. Tape media sucks
    • People don't care about quality! If people cared about quality Microsoft would be out of business, Airlines would have decalred bankupcy years ago, and NO ONE would eat fast food.

      Your assessment is too simplistic. People care about many things, one of which is quality. Furthermore, they have different wealth and different preferences.

      The Microsoft example proves that you can sell low quality software if it is easy to use - it does not prove that it is impossible to sell high quality software.

      Similarly, airlines sell first class and coach class seats. Some people eat at McDonald's and others at McCormick & Schmick's.

      Tor
    • Re:no (Score:2, Insightful)

      by Goldsmith ( 561202 )
      People don't care about quality, but they care about size.

      A videotape is a lot larger than a CD, and 10 videotapes weigh a LOT more than ten CDs. CDR, DVDR or something similar will eventually replace videotapes simply for that reason. You make an excellent point that people care a lot more about what is easy and what everyone else is using, but those same lazy people don't want to deal with something clunky and heavy when small and light will do.

      I will agree that most people won't use CDR type media until it's as easy to use and as commercially available as VHS. Until then, it will be like most people are unaware you can even use a CD to record video.
    • Re:no (Score:3, Interesting)

      by sheldon ( 2322 )
      Bizarre. I care about quality, which is probably why I'm not interested in using CD-R for video recording. I've been experimenting lately with recording video from my WinTV card to my harddrive, and in order to get reasonable quality I need to record at around 640x480 streaming at somewhere around 4 Mbps. That results in about 2 Gigs for a one hour program.

      Can you fit 2 Gigs on a single CD-R? Didn't think so. What I could fit on a CD-R would look like crap on my 51" HDTV set.

      As far as the Microsoft comment. The sad thing is, as poor quality as software is these days Microsoft software is higher quality then the competition.
  • by trailerparkcassanova ( 469342 ) on Wednesday October 23, 2002 @04:42PM (#4516929)
    storing video on punch cards. This would be great for editing as I could just pull out a stack of cards and insert it into another stack.

    Has anyone else done this?

  • by HotNeedleOfInquiry ( 598897 ) on Wednesday October 23, 2002 @04:43PM (#4516934)
    Answering your question would be a violation of the DMCA. Sorry, ask Jack and Hillary.
  • by Real World Stuff ( 561780 ) <real_world_stuff&hotmail,com> on Wednesday October 23, 2002 @04:43PM (#4516936) Journal
    This is an ongoing discussion at Plasma [plasma.com]. People with the bucks have been contemplating this for a while. Be sure to read up on the forums for the technical details as well. More info here [cwc.net].

    Please note there are solutions that require money. How cheap are you going to be?
  • by WittyName ( 615844 ) on Wednesday October 23, 2002 @04:43PM (#4516941)
    Insert disk and hit record, for a price point of $200.00 when it is in volume. And 2.40 for a CDRW?!? Just jump to DVD(+-) RW. They are only $6.00, and getting cheaper, and would hold about as much as a long video cassette at similiar quality. Also, tapes are not reliable either. They are only good for about 100 plays.
  • is it dirt? (Score:4, Insightful)

    by Anonymous Coward on Wednesday October 23, 2002 @04:43PM (#4516945)
    Are you sure the discs are not getting dirty w/fingerprints, dust, etc.? Such things can cause a lot of the problems misattributed to media failure...
  • by inaneboy ( 306740 ) on Wednesday October 23, 2002 @04:43PM (#4516946)
    .13$ a CD-R, and you get to keep it forever.

  • 30 to 40 (Score:3, Insightful)

    by _ph1ux_ ( 216706 ) on Wednesday October 23, 2002 @04:45PM (#4516972)
    well i know that the specs claim for many many more rewrites that 30 or 40.

    but I am also amazed that you have even actually used any of your discs that much. I would expect that if your using the CDs that much - they'd get scratched up and ruined long before you killed them via to much burning.

    I know that all my CDs are treated as a trash commodity that i just toss out when it starts getting bad. or I pre-emptively burn another copy of anything that is getting a lot of use - and throw out the other when its scratched up enough.

    How much watching do you do to get 30 or 40 burns on a single RW?
  • CDRW (Score:2, Funny)

    by Yablo ( 98362 )
    you mean people actually /use/ CDRW discs?
  • by Anonymous Coward on Wednesday October 23, 2002 @04:46PM (#4516975)
    You should take a look at the GNU version of TiVo called GnuVo. It's pretty nice except it won't let you watch any shows about capitalism.
  • CDRW is too small. Yea yea, compression blah blah. In order for a movie to fit on a CDRW the quality is as bad or worse than VHS.

    This [panasonic.com] on the other hand shows significant promise. DVD recordable, with a hard disk and some nice Tivo like features. Also, does MP3s etcetera...
  • by Geminatron ( 616988 ) on Wednesday October 23, 2002 @04:47PM (#4516990)
    A good place to learn how to convert various media to burnable (S)VCD format can be found at http://www.vcdhelp.com [vcdhelp.com]
  • by Ryu2 ( 89645 ) on Wednesday October 23, 2002 @04:48PM (#4517004) Homepage Journal
    Anyone examined a magnetic video tape's quality after 30-40, let alone 1000 rewrites? It's not too great either.
  • I've been recently trying to make VCDs under linux from some various episodes of Seinfeld. I got the "mvcdencode" program with mplayer to work. But it didn't /really/ work. The lips were desync'd BADLY, the people moved slowly, aspect ratio was weird. I was wondering if anyone had a good program for making VCDs under linux. The current process seems to be:

    * decode it using mplayer into raw yuv and pcm audio
    * Rescale, framerate the yuv
    * encode the raw yuv to mpeg
    * encode the pcm to audio mp2
    * use mplex to encode audio and video together
    * use VCD tools to create .cue and .bin files for cdrdao

    Obviously, using this hack of tools leads to the process being very slow and very vulernable to failure since at each step a separate indermediate must be created. Does anyone know of a solution like tmpgenc under windows?

    TIA
    • by ecloud ( 3022 ) on Wednesday October 23, 2002 @06:04PM (#4517668) Homepage Journal
      I successfully made a couple SVCDs; but I started with digital video (from a digital 8mm camcorder) and played them on a DVD player (a Sampo model - they are probably the most versatile and hackable players). I didn't have any sync problems, but the video quality left a bit to be desired (it looks short of VHS quality to me, even though encoded at SVCD bitrate, and thus I can only get 1/2 hour on a disc). I did subtitles and of course they were the worst part to encode. I used MainActor for editing and subtitles; but video output from Kino is just as good, it's only that Kino is a bit under-featured at this point, so I got MA as a stopgap (and don't recommend it - it crashes a lot). SVCDs and VCDs can have chapters like DVDs, so it's best to put each chapter in its own AVI file (besides, AVI files have length limits - 2 gigs or something like that).

      Here are my notes about how I made one disc:

      edit-??.avi are exported from maseq using AVI-mjpeg, default quality, 720x480, 30fps, interlace A, de-interlaced

      lav2yuv -A4:3 edit-01.avi | mpeg2enc -f4 -q6 -I0 -r32 -h -o wedding-ch1.m2v

      lav2wav edit-01.avi | mp2enc -V -o wedding-ch1.mp2

      mplex -f4 -V wedding-ch1.mp2 wedding-ch1.m2v -o wedding-ch1-svcd.mpg

      ...etc. for other AVI chapters, to produce interleaved MPEG files in the right format for SVCD; then...

      vcdimager -tsvcd -c wedding.cue -b wedding.bin -l "Wedding" --volume-count=2 --volume-number=1 wedding-ch1-svcd.mpg wedding-ch2-svcd.mpg wedding-ch3-svcd.mpg wedding-ch4-svcd.mpg wedding-ch5-svcd.mpg

      cdrdao write --driver generic-mmc-raw --device 1,1,0 wedding.cue

      I wrote a script for this encoding project and went to bed; it took a long time.

      I wondered if I got some quality degradation by exporting from MA in motion-JPEG format, rather than keeping it in native DV format, and then encoding to MPEG. Ideally some of the JPEG frames would just directly become keyframes in the MPEG output; but in this case I was scaling too, so that's not possible. Anyway most of the output formats in MainActor for Linux have bugs, and MJPEG happened to work well.

  • by hackshack ( 218460 ) on Wednesday October 23, 2002 @04:54PM (#4517050)
    I don't doubt the quoted figures of "1000 rewrites" for CD-RW media, for the reason that the crystalline substrate which stores the data proper should last around that much, chemically. In my experience, it's the physical disc which fails- scratches from handling, pitting on the reflective aluminum layer, etc.

    CD-RWs reflect around 25% of the read laser, as opposed to CD-Rs which reflect around 75%, and pressed CDs which reflect close to 100%. When the signal-to-noise ratio is this low, the A/D circuitry has a hard time keeping up even with minor defects- fingerprints and dust are much more deadly on a CD-RW than on a CD-R.

    In my experience, the first burn to a virgin CD-RW delivers CD-R-like readability, but once you rewrite it even once, the drive has to work a lot harder. I used to treat my CD-RWs like floppies, carrying them between the lab and my home, playing with them while waiting for an operation to complete, etc. and got maybe 4-5 rewrites on average. I then started keeping them inside jewel cases at all times, exposing them for a few seconds to put into the drive, and immediately got 20+ rewrites out of them.

    Also, we were using really bad drives at the lab (some early HP CD-RW burners which often rejected discs) and when we upgraded the machines (to better HP burners, in late 2001) rewritability literally doubled for me to about 40+ rewrites. So the type of drive makes a difference as well IMHO.
  • I've tried CDRW disks from several manufacturers

    I don't even have a CDRW drive myself, but I do know that 30-40 rewrites is way too little. If I were you I think I would blame the drive. Bad laser maybe? Without knowing much, I assume you could also try changing your burner SW it would seem logical that you can either conserve the disk or torture it by the SW - maybe you could for example extend the life and get more bang per $$ by not utilizing each disk 100%. This way, the burner could burn it with a significantly different pattern every time.... Or then again, maybe everything I guessed is utter crap :)

  • Possibly the compression scheme, however I have found that quality doesn't suffer on the burned disc. It all matters in the quality of the item being recorded/transfered and at what depth and sound. Now, while I wouldn't use CD-RW to do that (I am lazy and would just watch on the computer unless it was an ACTUAL movie I was watching), the medium has nothing to do with the quality of the original copy/mpeg. Yes, if too much compression is ued for the sake of space, the quality of the image (and sound as it is what takes up the most space) will be sacrificed to fit "more" onto one disc. I have found that 45 minutes per CD-R gives me a High quality image, and while it is only 45 minutes, that is just enough to remove the commercials from the captured file.
  • perfect (Score:5, Funny)

    by tps12 ( 105590 ) on Wednesday October 23, 2002 @05:04PM (#4517121) Homepage Journal
    most of the CDRWs I've tried only last about 30-40 rewrites before they start showing significant data dropouts (almost always at the start of a recording)

    Sounds like you've reproduced the VHS experience accurately.
  • Answer (Score:5, Insightful)

    by Viking Coder ( 102287 ) on Wednesday October 23, 2002 @05:04PM (#4517124)
    how many rewrites do most people expect from their CDRW media

    Zero. Actually, I find that CDRW are actually CDW. I can write to them, but I never expect to be able to read back from them. I've tried on dozens of CDRW drives, and I've never had luck archiving for a month or more on CDRW. Sure, "most" of the time it works - but it falls far short of my expected success ratios.

    I've learned not to trust CDRW. I always use CDR instead.
  • Tape and discs (Score:3, Interesting)

    by djtripp ( 468558 ) <djtripp&gmail,com> on Wednesday October 23, 2002 @05:05PM (#4517137) Homepage Journal
    In the past 5 years since I puschased a DVD player, I have watched a VCR tape on average 3 times a year. Mostly becasue corporate videos came to me that way, and of course Lucas.

    In the past years since I purchased TiVo, I have never recorded a tape, unless I was lo-teching for an unfortunate friend.

    I still think that CD-R's are a more reliable medium, and still, in most cases a faster medium. But if you get right to it, what happens when you recorded a video on a tape, over and over and over. Or watched the same tape over and over and over, the picture quality gets worse and worse.

    Phillips is now selling a DVD-RW for such purposes, so It does look like the video tape has one more nail in it's coffin.

    To make a TiVo clone would be cool, but to make one that will output to CD's, CDRW's, or DVD's would be great. (But still it's a waste of time to dupe a DVD if you can't get DTS ot Dolby Digital on it...)
  • I seem to remember reading that the VCR has already begun to be phased out. Circut City doesnt even carry them any more. I remember reading that one of the major makers has already started to slow production of them. I think that with things like DVRs and DVD-R/RW/ect options comming just around the corner ($300 or less) VCD's are just not really going to be an industry supported medium. What do u guys think? I am writting this question in extreme hast as my professor is about to start bitching at my for not paying attention (I love campus wide wi-fi =] ) Got to dip!
  • by MarvinIsANerd ( 447357 ) on Wednesday October 23, 2002 @05:10PM (#4517160)
    Unless your device supports capturing of original closed captioning information onto the CD-RW's - meaning you preserve the information present including the stuff in the vertical blank interval and replay it on playback - you will never be allowed to bring this device to market as a consumer VCR replacement. As far as I know the SVCD format does not have any built in mechanism for this. There are certain things you need to do to meet FCC requirements before this device will be allowed to be sold in the USA market. Same rules applies to closed captioning decoders being required in all TV's 13" or larger.
  • by Anonymous Coward
    CDRWs are too unreliable and have too little storage per disk. Hard drives are very reliable (compared to CDs) and can hold very large files.
    Price/Performance comparison:

    CDRW disks [newegg.com] - $30 for 50 700MB 10x disks - $0.857 per GB - 1.458 MB/s transfer rate (assuming 10x)
    Hard drives [newegg.com] - $141 for 120GB 5400RPM drive - $1.175 per GB - 40 MB/s transfer rate

    Replace your CDs once and it has already paid to use hard drives instead. As an added bonus, you also get a transfer rate equivalent to 274x in a CD drive. All you need is a video card with TV-out.
  • by Audacious ( 611811 ) on Wednesday October 23, 2002 @05:31PM (#4517376) Homepage
    That this is not one of the things the RIAA and MPAA ever say? According to them - they last forever and always make perfect copies. Maybe this should be brought to their attention?

    And yes, I've written and pointed this out to my reps. :-)

    When companies talk about MTBF, or number of re-writes, or anything like that you have to remember these few rules:

    1. They were done under ideal conditions and not your normal, everyday, household conditions.

    2. They count every time they were actually able to do whatever. (Like in being able to write to the CDRW disk they will count even partial writes in order to boost their numbers.)

    3. They don't care if they make outrageous statements. It takes a very long time to prove them otherwise. (Take the cigarette industry - PLEASE! Look how long it's taken to prove them wrong. [And they are STILL fighting it in the courts.])

    It used to be that if you cut whatever the company said in half you could be close to what the actual figures were. Now it's about a tenth of what they say. Not that all companies are like this. But there are quite a few.

  • by cookie23 ( 555274 ) on Wednesday October 23, 2002 @05:40PM (#4517475) Homepage
    I built a similar system myself, basicly a tivo built out of a shuttle SS51G and a all-in-wonder. The problem I've foud is that the CDRW is just too small to replace a VHS. A MPG and standrard VCD quality is about 600 MB per hour, so a CDRW only holds an hour of TV per CD. Thats great for 1 hour long show but it doesn't work too well when you want to store a movie or a longer show. Also I mainly store serries of shows (like star trek) , its far better to have a dvd+r with several episodes of the same show then have to swap through many cds.
  • Simple Solution (Score:3, Interesting)

    by timeOday ( 582209 ) on Wednesday October 23, 2002 @05:46PM (#4517524)
    I don't bother with CD-RW, I just use CDR. I only buy them when they're "free after rebate," which between OfficeMax, Staples, BestBuy, and Compusa, is about every other week.
  • DVD-R (Score:3, Interesting)

    by RatBastard ( 949 ) on Wednesday October 23, 2002 @06:11PM (#4517746) Homepage
    I got a Pioneer DVD-RW drive and just put stuff to DVD. Sure, DVD-Rs cost a bit, but I only put things I want to actually keep on them. If I'm not going to hold onto the video for a while I jkust leave it on the hard drive.

    I didn't go with (S)VCDs because my DVD player (XBox, actually) doesn't play them.

    The cost of entry is higher, but the quality is far superior than VHS (unless you're trying to record off of the local Fox station, but that's their fault).

  • Do i in real time! (Score:3, Interesting)

    by Anonymous Coward on Wednesday October 23, 2002 @06:16PM (#4517785)
    Last year, I've written my thesis work about recording VCDs in real time. I have a simple command line tool you can run to record analog TV (with small changes probably from any source) to your CD writer. The code is GPL, based on VCDImager and somewhere in the VCDImager repository.

    The thesis text is a bit dated by now but you can still find it at http://users.evitech.fi/~arndb/project/htmlmain/ [evitech.fi]

    Arnd Bergmann
  • by brunes69 ( 86786 ) <slashdot@nOSpam.keirstead.org> on Wednesday October 23, 2002 @06:40PM (#4517980)

    Why are you using re-writes at all? You can get a spindle of CDR's nowadays for $16.00 CDN on sale. (Must be $10 US?) That's 10 cents a disc, and you get to *keep* them. You are meanwhile spending 2.50 on a CDRW that you say can only be burnt 30 times, or 8.3 cents a burn. Seems to be it just isn't economical at all, when you could be spending pretty much the exact same amount and archiving all yoru movies instead of wiping them.

  • by akb ( 39826 ) on Thursday October 24, 2002 @02:39AM (#4520031)
    What I like most about this question is premise must strike fear in the hearts of the MPAA and other big media goons that are reading it. The premise is a recipe for a p2p video experience. The MPAA and the perpetrators of the DTV fiasco are hoping to eke out some more life for themselves by trying to convince people they need better quality and they want to pay more money for it, oh, ignore the chains that come with it.

    But your question demonstrates that you don't value what those hucksters are trying to sell you, you want flexibility. And it just so happens that flexibility means you can download video in a reasonable amount of time and store it on cheap media, ala mp3.

    I had a Dr Who hankering the other day, hadn't watched it in years. I don't own a TV, I probably watch a sitcom every 3 months or so and am blown away by the crap on TV, I've never been in a household with cable. I downloaded maybe 15 vhs-ish quality Dr Who episodes as divx over a couple nights and watched them over the course of a week, haven't felt the need to watch them or other movies since. Now that's an experience that big media has no interest in providing me.

"The vast majority of successful major crimes against property are perpetrated by individuals abusing positions of trust." -- Lawrence Dalzell

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