View Full Version : Technically, is it possible to record HD on a DVD ?
tuna-head 08-09-07, 09:17 AM I know none of the recorders out there do this. But technically, can it be done ? We have camcorders out there now that record HD on DVDs don't we ? just curious. I wonder what limitations there'd be or just what kind of quality one might get from the ole DVD.
HomeVideoGuy 08-09-07, 09:40 AM I don't think the problem is so much the physical DVD but the encoder/decoder and the rest of the electronics in the recorders. The DVD itself can hold 4.7G of data. HD compressed with MPEG-2 I believe is roughly 5 -7G per hour. So a regular DVD could barely hold an hour of "data". You could compress with MPEG-4 to a DVD but that would only be a "data" file stored on a DVD readable only in a computer drive. Thus, the powers that be decided it was best to develop blue laser technology: smaller light beam + smaller bits on a disc surface = more "data" on the new disc technologies.
If they were nice, they could produce DVD recorders that recorded HD to standard DVDs; much like the SVCD format could hold a half hour of "DVD quality" MPEG-2 compressed video on a standard CD. But then, with multi-layered DVDs, there would not be much need for a blue laser based device :)
BOBKART did this some time ago...got a short amount of HD on a DVD, and it was playable. I tried to find his postings on that subject but it may be in the stuff they recently offloaded and haven't put into an Archive yet. Bobkart hasn't posted in a while now.
BOBKART, where are you when you're needed?
Rammitinski 08-09-07, 05:22 PM Yeah, now that you mention it, where in the heck HAS he been lately?
Yeah, now that you mention it, where in the heck HAS he been lately?His last post was 3/27/07
HIs last visit to AVS Forum was 6/23/07
I guess he just got tired of us and moved on.
videonut 08-10-07, 01:25 PM One of our members wrote that he was recording a full movie onto one D/L SD DVD at 740P. I sent him an IM about it, but he suddenly became quite vague (maybe he thought I was a studio cop or something?).
Anyway, I found the following on C-Net:
Even though HD requires more storage space, there are several alternative high def formats for which you can record HDTV shows/movies to DVD. DivX and WMV9 are formats that both allow you to save your HDTV recordings on today's DVDs. For example, the DivX codec can compress an MPEG-2 file to nearly one-tenth its original size so you can actually save high def material onto a DVD. Also there are an increasing number of DVD players available that support these formats and some DVD players (Avel Linkplayer is one that comes to mind) that can be networked (Wireless and wired) into you home network so you can also play your saved HDTV recordings in case you don't have a dedicated DVR. On the limiting side, it seems most dedicated DVRs don't allow you to transfer your saved programs to other devices.
bobkart 08-10-07, 08:31 PM Got an email from wabjxo that I might be able to help here.
I've made a dozen or so single-layer DVDs (4.7GB) containing HD material (1080i), not downconverted to 480i, playable (only) on HD DVD players.
I actually learned how to do it thanks to a thread in another section of AVS Forums, which I can't find now.
It goes something like this:
1) Record HD material onto HDV camcorder (or you could have another source of HD material of course).
2) Transfer the HDV material from camcorder to PC using HDVSplit (an HDV capture tool like WinDV is for DV material). This results in a *.m2t (MPEG-2 Transport Stream) file.
3) Convert this *.m2t file into an MPEG-2 Program Stream (*.mpg) using tools like VideoReDo or Womble.
4) Import the *.mpg file(s) into ULead DVD Movie Factory 5 Plus, which can author HD DVD folder/file structures suitable for burning to either HD DVD or standard DVD discs. No re-encoding of the imported *.mpg material is necessary for this.
5) Burn the resulting HD DVD folder/file structure using Nero 7. There are some settings here that are critical to making it work. UDF, and Xbox Compatibility Mode off the top of my head.
Apparently, of the two High-Definition DVD standards (HD DVD and BluRay), only HD DVD supports recording/playback to/from the old DVD media (single and double/dual layer).
If that thread could be found that describes the process in great detail, a link to that would suffice. But it looks like there has been some rearrangement of the Forums lately, and that thread is no longer sticky at least, completely gone at worst.
I recently tested the upper limit for how much HD material would fit on a single-layer DVD, by calculation it is 24 minutes (using the 25Mb/s bitrate of HDV), and sure enough I was able to fit exactly 24 minutes with very little room to spare.
(I guess the original question of this thread is just "is it possible", so maybe just "yes" would have been sufficient?)
Welcome back, bobkart! I knew you'd have the answer...in spades! :)
I tried to find one of your posts on the subject, but they just removed a bunch of stuff for archiving, and I don't think it's actually been archived yet. :(
bobkart 08-10-07, 09:12 PM Thanks for the welcome back wabjxo.
A search at videohelp.com turned up a post (http://forum.videohelp.com/topic318122.html#1635018) in which I gave a link to the AVS Forum thread (http://www.avsforum.com/avs-vb/showthread.php?t=705146) in question.
dangerdoc1 08-10-07, 10:45 PM I know none of the recorders out there do this. But technically, can it be done ? We have camcorders out there now that record HD on DVDs don't we ? just curious. I wonder what limitations there'd be or just what kind of quality one might get from the ole DVD.
I have an entire movie in 720p on one DVD that I purchased from a store shelf about 4 years ago. T2 extreme edition if memory serves. It looked pretty decent played from my computer to a 22" widescreen computer monitor.
Yes it is entirely posible. With modern compression, it should be posible to record 2 hours of 1080p that would look pretty good on the average HDTV.
I have not viewed them but there is an entire subculture trading HD content compressed to fit on one DL disk. Of course, that is probably the reason that we don't have players that play or record this hirez content.
bobkart 08-11-07, 04:40 AM Some clarification is called for it appears.
There is a difference between writing one or more HD video files from a PC to a DVD, such that those files can later be read back on a PC and played with some media player, and the situation I described, which yields a DVD that can be played back on a standalone HD DVD Player. The former has indeed been going on for years, there are hundreds of WMV-HD DVDs available on Amazon, for example, but you need a PC to play them back.
To make a DVD that contains (for example) HD material recorded from an HDV camcorder, without the requirement that it play back on a standalone HD DVD Player, you can skip half of the steps I listed. Simply transfer the video from camcorder to PC and burn the resulting file to a DVD. No need to covert to MPEG-2 Program Stream or author any HD DVD folder/file structures, or use any special burning settings as is required if you want it to play back on an HD DVD Player.
I know none of the recorders out there do this. But technically, can it be done ? We have camcorders out there now that record HD on DVDs don't we ? just curious. I wonder what limitations there'd be or just what kind of quality one might get from the ole DVD.
I'm sure that these units are for people with very deep pockets (especially when......or should I say......if, they become available in the US)......but
BluRay DVD recorders have been available in Japan (and perhaps elsewhere)
for (I believe) two years already! They're designed for HD and the specs are amazing, but the blank media is very expensive!
Perhaps we'll get their discontinued, leftover models in five years or more! :(
We're so behind, it's truly pathetic!! :eek:
Here's a person in a HDTV forum (http://www.avsforum.com/avs-vb/showthread.php?p=11119891&&#post11119891) who's recording HD 1080i and 720p programs to a std DVD and gets 1 hour of HD on a SL disc and 2 hours on a DL disc. Like bobkart, he then plays the DVDs in his HD-DVD player.
They're just starting a discussion of his process.
bobkart 08-13-07, 02:17 AM As far as how much HD material you will get on a certain size disc, it's just down to the bitrate involved. As I mentioned, 24 minutes at 25Mb/s just fits on an SL disc. About 44 minutes for a DL disc at that same bitrate. To get an hour on an SL disc you need to bring the bitrate down to 10Mb/s (same as maximum SD bitate supported by DVD). If they're using MPEG-2 I suspect the compression artifacts are easily visible at that level of compression. Haven't checked that thread yet, but there are more advanced compression techniques supported by HD DVD (and BluRay), so that could help.
techgurudude 08-13-07, 04:43 PM I'm sure that these units are for people with very deep pockets (especially when......or should I say......if, they become available in the US)......but
BluRay DVD recorders have been available in Japan (and perhaps elsewhere)
for (I believe) two years already! They're designed for HD and the specs are amazing, but the blank media is very expensive!
Perhaps we'll get their discontinued, leftover models in five years or more! :(
We're so behind, it's truly pathetic!! :eek:
Actually, I have seen the Blu-Ray recorders for PC for sale here in the U.S. Not the cheapest accessory in the world, but it is new technology, and it is sought after, so what do you expect, lol.
bobkart 08-13-07, 05:01 PM I don't think a BluRay recorder qualifies as a yes to the original question which asked about recording HD material to a (standard) DVD. (This is more a response to slprp1's post.)
bobkart 08-13-07, 05:03 PM Here's a person in a HDTV forum (http://www.avsforum.com/avs-vb/showthread.php?p=11119891&&#post11119891) who's recording HD 1080i and 720p programs to a std DVD and gets 1 hour of HD on a SL disc and 2 hours on a DL disc. Like bobkart, he then plays the DVDs in his HD-DVD player.
They're just starting a discussion of his process.
I checked that thread, he's linking to the same thread I linked to as far as what process he's using.
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