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i, personally, won't be rebuying my collection. i mean, i bought my collection to *last* me. granted, the media may not last forever nor may the technology to even read them last forever (ie. it may be replaced by something better), but... thanks to DeCSS, the actual content can last forever. i can back it up and transfer it to progressively next generation media for as long as i please, and unlike with analogue copying, these transfers will be the same high quality they were when i purchased them. now, this hd-dvd standard may provide higher quality, but it'll be that much more riddled with copy protection, and blah.

also, for those currious... the name of the discs that the DVD forum approved are advanced optical discs. you can read about it here:
http://www.dvddemystified.com/dvdfaq.html#3.13

the DVD FAQ states one of the features of DVD is "Automatic seamless branching of video (for multiple story lines or ratings on one disc)." So it wouldn't be that hard....

DVD FAQ 1.15 - What happens if I scratch the disc? Aren't discs too fragile to be rented?

States that DVDs have more error correction features built in then regular *data* CDs, which would make them less sensitive to damage.

Audio CDs, OTOH, are a bit more resistant because the CD player can just interpolate over the problem bits until things get too bad to cover up.

How Long Do DVD's Last?

One other thing I should have mentioned. Who cares about violet lasers? The linked to article points to a DVD recorder , not a player. The various manufacturers have yet to finalize on a format for next generation, pre-recorded DVDs (presumably High Definition). According to the DVD FAQ site, there are at least 6 competing formats, and it will be a while (if ever) before they standarize on a single format. Waiting it out will be years. Buy a player.

DVD Demystified

You're missing two details: First of all, VHS isn't 240 lines of vertical resolution, it's 240 lines of horizontal resolution. Still frames (ie frames without motion) easily have more than 240 lines of vertical resolution, even on crappy VHS tape.

But the most important thing you're missing is that VHS is interlaced -- you have 60 different images per second in an interlaced format. If you dump to DivX at 30 frames per second you are effectively throwing away half the motion (you are halving the "framerate", to use computer terms). This is far worse than throwing away resolution if your source was live video, like a sitcom, sporting event, newscast, documentary produced for television, etc.

"Burn DVD's direct from VHS tape. I have software that will do this. Expensive and the DVD's won't even hold a VHS tape if it's 2 hours long. Good quality with no degradation."

You are so wrong. Most people tend to think DVD is like 720x480 MPEG-2 with high bit-rate. They are wrong, too.

If you degrade the resolution to 352x480 (as is possible with DVD Standard) and lower the bitrate you can easily get one VHS tape for one DVD disc. Your software and your DVD player should support this, because it is in the standard.

Considering, that your VHS has no more resolution anyway, this is IMHO the optimal situation. I will not go to lifetime of DVD-R discs, etc. because you can easily make identical copies (no D/A or A/D conversion) after you have one copy. Discs will probably be cheaper in the future, too.

Try some of these:

• dvdrw.com - Official DVD+RW Site
• dvdrhelp - lists some differences
• dvdplusrw.org - has some info on dvd+r plus some comparisons
• DVD FAQ
• Pioneer's Info
• DVD Forum - consortium supporting DVD and DVD-R, but not DVD+R

Off-topic, but i'll bite. DVD stands for DVD. Used to stand for Digital Versitile Disk or Digital Video Disk, but now just stands for DVD[referenced from DVD FAQ]

There are already 4 standards out trying to become the next DVD standard. One format is to use standard DVD discs and MPEG-4. The other is to use Blu-Ray discs to deliver HD-DVD using less compression for a better image.

Most people of course are in support of the new Blu-Ray discs but just like Beta\VHS and DVD-A\SACD there are competing formats that may delay the technology.

Click here to support ONE HD-DVD FORMAT

These signals will be compressed much more than the average DVD.

Not to mention they will be interlaced

and lower resolution

with some bit errors introduced.

These signals will be compressed much more than the average DVD.

Not to mention they will be interlaced

and lower resolution

with some bit errors introduced.

From what I've always understood, Digital Video Disc was the original meaning and Digital Versatile Disc was just a clumsy attempt to reinvent the name that never stuck. Anyway, that's what the DVD FAQ says.

The transfer rate for a 1X CD-ROM is 150 Kbps. The transfer rate for a 1X DVD-ROM is 1108 Kbps, with the media only having to spin 3X faster due to higher data densities. You can find out more here.

A 16X DVD-ROM would spin at the same speed as a 48X CD-ROM and would transfer 21.13 MBps (megabytes per second). This would take about 3.7 minutes to fill a 4.7 GB disk.

"I don't really see the point [...]. A DVD can hold much more information"

Did you bother reading the article? Or, do you actually understand the DVDs that you seem so fond of?

This mini CD can hold 27GB of data. DVDs are much smaller, as well as being four times the diameter. The biggest DVDs (dual-layer, dual-sided), which I doubt you see very often, are just over half the capacity.

No, DVD is interlaced. RTFSpec. Further, DVD has a max resolution of 720x480x60, or 720x576x50. Yes, they could change the spec, but then they could change the spec to make waffles, too. Hardly relevant to the installed base.

You *can* get 720x480x30 progressive from DVD, but it requires manipulation of MPEG2 flags that is almost always done wrong. This is why the Progressive-Scan DVD players that actually work ignore the flags and watch the cadence of the fields to construct progressive frames. And this only works from progressive sources like film. If you shoot on video, it's interlaced. Game over. And the same applies to 1080i. If you have a display that can do 1080p, you can do the same inverse telecine that you can with DVD.

Yes, DVD supports 9.8Mb/s. ATSC HDTV supports up to 19.3Mb/s. 1080i looks like hell at 9.8Mb/s, and you only get around an hour per DVD layer at that rate. (Yes, 2hr movies will fit on SS/DL discs, but HD is still going to look like hell.)

Oh, and if you really want progressive, ATSC includes a few 720p resolutions (ABC uses 1280x720p) but they still require more than 10Mb/s to look good.

Oh, and DVD-Video is at v1.1.

ObLink: DVD FAQ: 2.9-Does DVD support HDTV?

Anamarphic, in fact, actually "splits the difference" between NTSC and HDTV on resolution. Anamorphic discs appear much better under HDTV displays than NTSC ones.

Every HDTV or DVD owner should understand anamorphic DVDs and/or read the DVD FAQ

DVD+R uses a similar dye-based, write-once medium, like DVD-R, giving it an equal chance of compatibility. In fact, basd on my research, the DVD+R might even be more compatible. It shares the same characteristics of DVD+RW in terms of how the writer identifies a disc and aligns itself for writing.

When you look at DVD-R, DVD-RW, DVD+R, and DVD+RW, they can be categorized along two axes:

1) R vs RW
The key difference here is in the physical recording medium. Write-once media uses dyes, which have relatively high reflectivity and thus play well with DVD-ROM/DVD-Players. Rewriteable media uses organic phase-change compounds that have low reflectivity, and hence confuse many DVD-ROM/DVD-Players.

2) + vs -
The DVD+R(W) vs DVD-R(W) discs differ in how they "communicate" to the writer. Essentially, writable discs have extra info not seen on stamped discs and ignored by readers. This info tells the writer what type of disc it is, and how to align itself for writing. DVD-R(W) uses groove recording with address info in the land areas. DVD+R(W) uses high-frequency wobbled grooves, which the writer uses to align to the disc.

Of course, Jim Taylor explains it better than I can in his DVD FAQ. I highly recommend his book "DVD Demystified Second Edition". Although it doesn't cover DVD+R, the updated FAQ does. This book really should be called "Home Audio and Video Demystified". The explanation of aspect ratios for 4:3 and 16:9 TVs is worth the cost of the book!

This is a huge problem. I've been thinking about getting a DVD player for the last 6 months or so, but there's a huge problem with figuring out which features do what. This DVD FAQ helped quite a bit. I've got to have one by the time Gigantic comes out, and I need to be able to play MP3 (oog would be great too) on it. What to do... what to do...
----------
check out the interactive web assistants at verbots.com.

I might have more sympathy for George Lucas if you could get the first three chapters on DVD. You know, Digital Video Disc.

There's no programming that the player uploads and executes.

Buttons on DVD menus can actually be set up to execute arbitrary sequences of code. However, in most DVD Videos the buttons are just links to other menus or parts of the movie, so I guess that is why you felt that there wasn't any executable code on the disc.

I've looked at the code that is uploaded and executed and no-one would dispute that it is executable code - it has assignments and conditional branches.

how did you determine (and what are) the "commands" the section B lists ? .. did you disassemble the code ?

The DVD FAQ has details about the nature of the commands on DVDs. The commands that were on the Warner DVDs that I looked at did not do anything very exciting - it was stuff like setting the audio language to match the setting on the player.

Shrug, the guy only wrote the DVD-FAQ, and the books been copyrighted for 2001. His FAQ is updated regularly, and has in fact been updated in the past week or so. I direct you to these FAQ entries, and you can decide from there if I'm right or wrong (I really could care less either way, I'm happy ST:TNG is making it out on DVD, be it 3 episodes per disc, 4, or 5)--

http://www.dvddemystified.com/dvdfaq.html#1.21 - [1.21] Why do some discs require side flipping? Can't DVDs hold four hours per side?

You might also find this question educational--

http://www.dvddemystified.com/dvdfaq.html#3.3 - [3.3] What are the sizes and capacities of DVD?

Yes, there are situations where this is false, after all, it IS VARIABLE BIT RATE encoding; but generally speaking, four hours of high quality video is possible on a single side dual layer DVD. If The X-Files has poor quality, I'd lay this at the feet of poor encoding practices (or simply someone lazy at Fox). As you said, it's definately not something that's easy (encoding MPEG2 properly) but it has been done. Plus, and I've noticed this on a number of DVD titles (movies and TV shows), for whatever reason, MPEG2 ruins dark sequences (which I imagine The X-Files has a lot of-- I stopped watching after the sixth season or so). This might be the nature of the beast, or it might be lazy encoders. =) I'm not going to pretend to know.

Shrug, the guy only wrote the DVD-FAQ, and the books been copyrighted for 2001. His FAQ is updated regularly, and has in fact been updated in the past week or so. I direct you to these FAQ entries, and you can decide from there if I'm right or wrong (I really could care less either way, I'm happy ST:TNG is making it out on DVD, be it 3 episodes per disc, 4, or 5)--

http://www.dvddemystified.com/dvdfaq.html#1.21 - [1.21] Why do some discs require side flipping? Can't DVDs hold four hours per side?

You might also find this question educational--

http://www.dvddemystified.com/dvdfaq.html#3.3 - [3.3] What are the sizes and capacities of DVD?

Yes, there are situations where this is false, after all, it IS VARIABLE BIT RATE encoding; but generally speaking, four hours of high quality video is possible on a single side dual layer DVD. If The X-Files has poor quality, I'd lay this at the feet of poor encoding practices (or simply someone lazy at Fox). As you said, it's definately not something that's easy (encoding MPEG2 properly) but it has been done. Plus, and I've noticed this on a number of DVD titles (movies and TV shows), for whatever reason, MPEG2 ruins dark sequences (which I imagine The X-Files has a lot of-- I stopped watching after the sixth season or so). This might be the nature of the beast, or it might be lazy encoders. =) I'm not going to pretend to know.

How much video you can stash on the disc also depends on the resolution and the quality of the compression.

Sure, they could've put more on each disc, but you'd likely have noticed the difference. In fact, if you use the maximum allowed bitrate (10.08Mbps), you can only hold about 107 minutes.

These facts all come from your DVD Demystified site with the help of my friend Math.

The only problem is that dual layer discs have that 'layer transition' effect on certain older or low-cost DVD players (the images freezes for a split second while it switches layers).

You wrote:

Yes and no. The DVD player just takes the signal on the disk and dumps it out to your TV, projector, etc. Generally the player doesn't care if the signal on the disk is PAL, SECAM, or NTSC.

Nothing is encoded on the DVD as NTSC or PAL or SECAM.

That is to say, I live in the USA, and I personally have a copy of ' South Park: vol 4 ', as released in Region 2. This disk is clearly labeled as 'PAL'.

I can play this disk in a 'region free' Apex player on my NTSC television, and it works fine because the Apex internally does the conversion from PAL to NTSC.

A friend of mine has another brand of 'region free' DVD player, and while the player plays the disk, his TV displays a severely distorted picture.

In other words:
DISKS CONTAIN PAL CONTENT, OR NTSC CONTENT, OR BOTH. A PAL DISK WILL NOT DISPLAY CORRECTLY ON A NTSC-ONLY AMERICAN TELEVISION SET.

I know this both from references and from personal experience. If you claim otherwise, prove me wrong.

• http://dvddemystified.com/dvdfaq.html#1.19
• http://www.dvdspecialty.com/faqs.html
• http://www.horrordvds.com/extras/articles/palntsc/

It's called RCE (Region Coding Enhancement). The DVD FAQ has some information, as does DVD Talk.

The best site I've found that goes through all the differences between DVD formats is in the DVD FAQ at DVD Demystified

The best site I've found that goes through all the differences between DVD formats is in the DVD FAQ at DVD Demystified

If you have been working on a project like this then you might have read the dvd faq. It mentions some similar projects that died from patent disputes.

The answer is that you Can. However none of the studios are doing so because the expense of multiple shoots of the relevent scenes, multiple editing, multiple certification by the censor boards and so on costs more than they think they will get back in increased revenue. The DVD FAQ has the explination.

"Is there a spec for it somewhere?"

"Is there a spec for it somewhere?"

I believe that in the early days, some Hollywood discs actually went out without CSS, or were region free. Of course, they keep quiet about them to protect the sales of more expensive versions in other markets. The DVD FAQ has lots and lots of good info.

I too have had experiences with FutureShop reps: I tried to buy a multi-DVD player/changer and told them that I needed one that supports CD-Rs... they told me that they only had one that handled CD-Rs, and it just happened to be the most expensive one there. After getting it home, I found that it didn't support CD-R's at all. Wankers! One of the few reasons I use FutureShop is their good returns policy ;)

Check out

http://www.dvddemystified.com/dvdfaq.html#4.3 for a nice compatability grid.

Because of that, I would go for price or bundled software.

As long as (which others have already said) there are more than one standard and nobody yet knows which standard will be the one that wins the race, I'm not buying.

Here is a quote from a faq:

There are six recordable versions of DVD-ROM: DVD-R for General, DVD-R for Authoring, DVD-RAM, DVD-RW, DVD+RW, and DVD+R. All recordable drives can read DVD-ROM discs, but each uses a different type of disc for recording. DVD-R and DVD+R can record data once (sequentially only), while DVD-RAM, DVD-RW, and DVD+RW can be rewritten thousands of times. DVD-R was first available in fall 1997.
DVD-RAM followed in summer 1998. DVD-RW came out in Japan in December 1999, but won't be available elsewhere until mid or late 2001. DVD+RW will be available in late 2001 or early 2002. DVD+R will be available in mid 2002.

From what I have read in the faq, CD+RW looks to be the kind of drive you should buy (this HP drive is such a drive).

Even better, here is a FAQ, see section 1.11, paragraph 2: http://www.dvddemystified.com/dvdfaq.html

Actually this is a DVD+RW drive. There are at least seven different standards for recording/pressing DVDs and they all have their pros and cons. A summary can be found here.

Indeed, having so many different standards is sure to slow the adoption of a recordable DVD format. But hopefully, someday everyone will use the same format and the media will be cheap. Witness the price drops (over time) that occurred with CD-Rs, and then with CD-RWs - the drives did not become commodities until the media did. Back in 1996, blank CD-Rs were about $20 each, as a point of reference. Be patient; we will have cheap recordable DVDs soon enough.

-all dead homiez

According to the rec.video.dvd FAQ, it is in fact a technical limitation. You're looking at four layers in one disc. Combine that with changers built to play only single sided DVD's, and you won't see many DVD-18's around.

I've heard that DVDs didn't look quite as good as laserdiscs when they first came out, but now that encoding techniques have had time to mature a bit more, DVD surpasses laserdisc in terms of video/audio quality. (Admittedly, it's not exactly an unbiased source.)

- From the DVD FAQ

DVD decoding in software? A DVD FAQ suggests a 400Mhz PIII if you don't use any hardware acceleration.
Adamation's personalStudio at least _alleges_ a 600 Mhz machine as a minimum for real-time video effects previews, etc.
Last year, someone at The Perl Journal wrote about capturing video and comparing individual frames; IIRC, using a specific optimized module, he captured video without dropping frames with a dual 500 Mhz machine... The Perl Journal site is down (pending transfer of ownership, probably) and I don't have that issue handy.

I wouldn't be surprised if there are killer apps - I mean, I don't know where to look for info on MPEG4/Divx :), but, well, what kind of application are you thinking about?

DVD can hold up to 16 GB (today). Check this link.

So we're at 6 (or so) discs. And 20 discs isn't a big deal. We just bought a family tree maker program that came on (gasp!) 20 CDs...

I think most libraries, and people needing quick USENET archive access could live with that.

1: U.S., Canada, U.S. Territories
2: Japan, Europe, South Africa, and Middle East (including Egypt)
3: Southeast Asia and East Asia (including Hong Kong)
4: Australia, New Zealand, Pacific Islands, Central America, Mexico, South America, and the Caribbean
5: Eastern Europe (Former Soviet Union), Indian subcontinent, Africa, North Korea, and Mongolia
6: China
7: Reserved
8: Special international venues (airplanes, cruise ships, etc.)

check this out for all you ever want to know about DVD. http://www.dvddemystified.com/dvdfaq.html

http://www.dvddemystified.com/dvdfaq.html#2.4.3

To quote:

[2.4.3] Is CD-R compatible with DVD?

Sometimes. The problem is that CD-Rs (Orange Book Part II) are "invisible" to DVD laser wavelength because the dye used in CD-Rs doesn't reflect the beam. Some first-generation DVD-ROM drives and many DVD players can't read CD-Rs. The formulation of dye used by different CD-R manufacturers also affects readability. That is, some brands of CD-R have better reflectivity at DVD laser wavelength, but even these don't reliably work in all players.

The common solution is for the DVD player or drive to use two lasers at different wavelengths: one for reading DVDs and the other for reading CDs and CD-Rs. Variations on the theme include Sony's "dual discrete optical pickup" with switchable pickup assemblies with separate optics, Sony's dual-wavelength laser (to be initially deployed on Playstation 2), Samsung's "annular masked objective lens" with a shared optical path, Toshiba's similar shared optical path using an objective lens masked with a coating that's transparent only to 650-nm light, Hitachi's switchable objective lens assembly, and Matsushita's holographic dual-focus lens. The MultiRead logo guarantees compatibility with CD-R and CD-RW media, but unfortunately, few manufacturers are using it.

Bottom line: If you want a DVD player that can read CD-R discs, look for a "dual laser" or "dual optics" feature.

An effort to develop CD-R "Type II" media compatible with both CD and DVD wavelengths was abandoned.

DVD-ROM drives can't record on CD-R or any other media. There are a few combination DVD-ROM/CD-RW drives that can write to CD-R and CD-RW. Current writable DVD drives (see 4.3) can't record on CD-R or CD-RW, although future versions will.

From DVD demystified FAQ, "The problem is that CD-Rs (Orange Book Part II) are 'invisible' to DVD laser wavelength because the dye used in CD-Rs doesn't reflect the beam."

See the section about DVD and CDR.