View Full Version : DVD-R quality
Mark Morikawa February 22nd, 2007, 01:12 AM now bare with me.
DVD-R quality doesn't seem very good. If I make a wedding DVD and put maybe 2 hours of footage with menus, the DVD picture quality seems to suffer. I am never able to put the max quality since there is so much information going into it. My question is, what DVD format do professionals use in the movie industry to put their movies onto DVD? because the quality of those DVD's are as good as it gets, and with much more footage than what I am putting on. or a better question is whats the difference between what i am doing at a consumer/prosumer level compared to what the industry is using. my DVD's are looking like crap.
Mathieu Ghekiere February 22nd, 2007, 01:41 AM Yes, you're right, I once made a documentary (for myself as a souvenir) of 70 minutes, with extras worth at an hour extra footage, and menu's, and the picture quality of the dvd was HORRIBLE.
So I divided the extras and main documentary over 2 discs.
Most of our technology (consumers) exists out of 1 layer discs.
Most dvd burners now CAN write in dual layer (2 layers). I have such one as well, BUT those Dual Layer blanc discs are very expensive (aren't they about 10-15 euros? In Europe?)
But that's what professionals use. Because of the extra layer they have 8.5 gigabyte instead of 4.7 gigabye AND they probably have much better encoding programs than we do on our home computer ;-)
Mark Morikawa February 22nd, 2007, 01:57 AM thanks for the info
thats what i thought was going on.
Robert M Wright February 22nd, 2007, 12:42 PM now bare with me.
DVD-R quality doesn't seem very good. If I make a wedding DVD and put maybe 2 hours of footage with menus, the DVD picture quality seems to suffer. I am never able to put the max quality since there is so much information going into it. My question is, what DVD format do professionals use in the movie industry to put their movies onto DVD? because the quality of those DVD's are as good as it gets, and with much more footage than what I am putting on. or a better question is whats the difference between what i am doing at a consumer/prosumer level compared to what the industry is using. my DVD's are looking like crap.
What encoder are you using?
Stephen Claus February 22nd, 2007, 06:00 PM I just recently tried to pack a 105 minute wedding video, plus menus, onto a single layer DVD. I fought for a week trying to get rid of horrible compression artifacts on a couple of clips. I finally gave up and delivered it on 2 discs. I've been blaming it on Apple's iDVD and hoping that when I can afford final cut studio, things will improve.
Matthew Craggs February 22nd, 2007, 06:41 PM Also, it's my understanding that feature films use hardware based compression that allows them to encode at a much lower bitrate.
Bill Davis February 22nd, 2007, 07:55 PM I think you're catching on that it's not the FORMAT that makes ANY difference in this. ALL DVD's are just buckets for bits. Whether it's a Plus R or a Minus R or an RW, if it's single layer - it's all the same size bucket.
The quality (or lack thereof) comes from the encoding and compression schemes employed.
Simple CBR (constant bit rate) encoding treats every frame the same - so a simple to compress scene like a talking head against a white wall takes the SAME data space on the disc as a "nightmare to compress" scene like tree leaves waving against a sky which has each pixel changing value for every frame.
More sophisticated encoders like VBR (variable bit rate), and particularly the multi-pass bit rate encoders - "look ahead" and figure out where the tough to compress sections are, and reserve a larger portion of the bit bucket for the harder to compress scenes.
The hardware that Hollywood uses, and the compressionist responsible for the master encode, can carefully ASSIGN differing compressions to different scenes and maximize quality. But you'll notice that even hollywood releases often get split onto two discs to avoid overrunning the bit bucket and revealing compression artifacts.
BTW, the "dual layer" idea DOES get you a double sized bit bucket, but remember that at some point the laser needs to "track" from the end of one layer to the beginning of the other and that can cause a layer switching pause. That "pause" might be important if you're in the middle of a critical scene.
Bottom line. Quality authoring and compression is often more complex than just "stick in a DVD-R and hit BURN"
Ervin Farkas February 22nd, 2007, 09:03 PM No wonder we get frustrated sometimes by the quality of our DVDs...
Can we expect our $100 encoder to work like the $38.000 Cinema Craft Vivo??? See http://www.cinemacraft.com/eng/xtream.html.
Andy Harding February 22nd, 2007, 09:43 PM May I ask what software you are using to create your discs? This maybe this is your problem, most software will compress more for larger ammounts of footage so it can get it onto the DVD so depending on the ammount and the settings of compression you will get bad or good as others have said.
Most software packages or more of the higher end ones allow you to control the compression on the final ouput maybe this is set incorrectly in your case.
Stephen Claus February 22nd, 2007, 11:09 PM Simple CBR (constant bit rate) encoding treats every frame the same - so a simple to compress scene like a talking head against a white wall takes the SAME data space on the disc as a "nightmare to compress" scene like tree leaves waving against a sky which has each pixel changing value for every frame.
Just so happens that tonight I'll be encoding my first outdoor wedding, shot on the edge of a lake, with lots of waving trees, grass, and water. I'll be attempting to dump 79 minutes of this onto a single layer--with iDVD!!
I AM TERRIFIED!!!
Kevin Randolph February 22nd, 2007, 11:21 PM As long as your menus aren't that complicated (lots of video in the menus), you shouldn't have a problem with iDVD on your project, Stephen. If you do use video clips in your menu, make them short and compress them yourself before you put them in the menu. That'll save space in "the bucket" for your feature video.
The main problem with iDVD is that it looks at the amount of info that needs to go into the bucket and decides on the bit-rate for you. If you turn down the bit rate enough, you can get 8 hours of video on a single layer DVD. Not that I would ever do that, but you could.
With the later versions of iDVD, you can (and I have) put just short of 2 hours (about 105-110 minutes) of video on one disc. Just keep the menus simple and you'll be fine.
I usually work on projects that are very short (15 minutes max) and I run into the opposite problem. iDVD cranks the bit rate up to 8 and I always seem to find people with older DVD players that won't read a disc encoded above a bit rate of 4. I've bought more than 1 DVD player for a client and just written it off as a cost of doing business (granted I get them the less expensive players).
Good luck, Stephen...
Hope this helps some one,
Kevin
Alessandro Machi February 23rd, 2007, 12:32 AM Any opinions on outputting the NLE to tape, then reinputting it to the computer and then burning the DVD? Might going from the tape version of the NLE reduce compression issues and perhaps give one a better quality copy?
Andy Harding February 23rd, 2007, 12:49 AM Any opinions on outputting the NLE to tape, then reinputting it to the computer and then burning the DVD? Might going from the tape version of the NLE reduce compression issues and perhaps give one a better quality copy?
Nooooooooooooo......
The compression is happending within the DVD software (producing the discs) not with your footage I'm sure it's top notch BTW :-)
If anything I'd invest in better DVD software I've used Encore and never had problems everything comes out just as it went in depending on grading of course ;-)
Alessandro Machi February 23rd, 2007, 01:00 AM Nooooooooooooo......
The compression is happening within the DVD software (producing the discs) not with your footage I'm sure it's top notch BTW :-)
If anything I'd invest in better DVD software I've used Encore and never had problems everything comes out just as it went in depending on grading of course ;-)
That's not what I was talking about. It's generally wise to make a tape back up once the NLE Master is completed. I'm suggesting that if one is having trouble making a high quality DVD copy, it might be wise to first export the NLE timeline to tape via firewire (since this step might happen anyways), than reimport the tape directly to the DVD authoring program. I'm not saying to do this on every job, but it might be worth trying if one is not happy with the DVD quality prior to trying this method.
Chris Barcellos February 23rd, 2007, 01:15 AM Are you guys doing interlaced or deinterlaced (progressive) DVD's. I use Premiere, and I was doing a disk with some wide angle scenic shots. I normally leave everything interlaced, but in this case it just looked nasty. So I dried render to deinterlaced .avi DV file, and encode from there, and ended up with a much sharper image.
Stephen Claus February 23rd, 2007, 05:35 PM Well, I got lucky this time and my outdoor wedding DVD came out okay. It's just too bad I have to rely on luck so much. When I get some more professional software, like final cut studio, at least I'll have some control over compression.
Kevin, thanks for the advice, although I got it too late for this project. I did notice some pixelation on the main menu video clip (only 28 seconds long) but I decided to live with it.
I've been using a kind of strange workflow that I have little control over, but I've been happy with the results so I haven't messed with it. It goes like this:
1) Capture 1080i HDV via firewire as Apple Intermediate Codec
2) Edit the AIC video in final cut express HD
3) Export as full-quality, non-independent Quicktime file
4) Import the Quicktime file into iDVD, set up menus, and hit "burn"
And viola, I have a letterboxed NTSC DVD that plays in any DVD player. The funny thing is, it has a progressive, filmic look to it when it's all said and done. So, I'm assuming that iDVD is somehow "downconverting" my 1080i to 480i--or is it making it 480p? Or is Quicktime always automatically progressive? Does anyone understand the black magic that's happening within the bowels of my computer?
Chris Barcellos, I don't even know if my DVD's are progressive. That's what I'm trying to figure out!
Waldemar Winkler February 23rd, 2007, 06:58 PM Just so happens that tonight I'll be encoding my first outdoor wedding, shot on the edge of a lake, with lots of waving trees, grass, and water. I'll be attempting to dump 79 minutes of this onto a single layer--with iDVD!!
I AM TERRIFIED!!!
Most of my weddings are shot outdoors and usually run 90 or more minutes. I limit run time to 1 hr, 45 min per disc, just to be safe. Never had a problem with iDVD so long as I used top quality media. Although the learning curve is a bit steep (was for me) DVD Studio Pro is a lot more satisfying and, once you get used to it, almost as easy as iDVD.
Prepare your DVD in iDVD slowly and carefully. Keep background music simple and short, use the least complex transitions, and you should be satisfied. A 90 min video on my G5 1.8 takes about 3 1/2 hours to encode and burn.
Benjamin Hill February 24th, 2007, 09:31 AM Bill Davis has made great points about how the encoding will make the greatest difference. I want to add that iDVD offers has very, very limited options for encoder settings, and I don't think it can recognize the compression markers you can embed in a QuickTime file with Final Cut. iDVD should be considered a very blunt instrument for the job. If you're working on a Mac then Compressor will offer a very high level of control over your end result.
Stelios Christofides February 24th, 2007, 10:48 AM I am using Ulead MovieFactory 5 for my DVDs and the results are excellent for 100 minutes video. Of course I am using good quality single layer DVDs.
Stelios
Vence Vida February 28th, 2007, 11:30 AM The quality of the DVD media is irrelevant in regard to the compression. That would be like saying "I had a great steak at Sullivan's Steakhouse last night. Of course, I used very expensive silverwear." No matter how expensive the silverwear, it doesn't change the taste of the food.
Don't misunderstand, media quality is important for other reasons: compatibility with your burner, compatibility with the client's player, consistency of the product from disc to disc, etc. However, it won't effect the quality of the image. If you're getting a decent image, it's because you're getting good quality compression. Movie Factory is what is giving you the good image quality, not the dvd media.
This goes back to the original post at the top of this thread. The idea that DVD-R is responsible for the poor image quality. As has been explained here, that is not it, at all. I remember the first DVD I burned, and how disappointed I was that it did not look like a Hollywood disc. Since then, I have learned some lessons about compression, but I still can't make an end result that is as flawless as a HW production. But it's like everything else in Hollywood. They throw insane amounts of money at every step of the process to create something that we just can't duplicate. The compression software, hardware, and technicians that they use dwarf what many of us can do with idvd, Studio Pro and the like. And don't miss the value of those technicians. They will do painstaking hands-on work to set the compression markers and rates from scene to scene and frame to frame to get the most out of the bitrate.
Stephen, I'm pretty sure your dvd is SD 480i. That would be the default setting for your burn. You would have to tell it to do progressive. I don't know if idvd can do that, I don't use it, since I have Studio Pro. I guarantee it is not HD 1080i. There is no way to put that much HD footage on an SD dvd.
Ervin Farkas February 28th, 2007, 01:15 PM Don't misunderstand, media quality is important for other reasons: compatibility with your burner, compatibility with the client's player, consistency of the product from disc to disc, etc. However, it won't effect the quality of the image... etc...
Except maybe dropouts on cheap blanks...
Alex Amira February 28th, 2007, 02:09 PM Except maybe dropouts on cheap blanks...
Well a dropout will only happen when your camcorder records to the tape...on the DVD you would get CRC errors...
This is more about compatibility than anything else.
90% of the time the CRC errors are due to the fact that people pick up a blank DVD and read that it is a x16 speed and they burn it at that (and skip on the verify part). I've learned by testing the slower you burn the less CRC errors and the more compatibility you will have. I go as low as I can on the burn (x4) even though my drive can burn at x18 and the disks are rated at x16. Another thing to keep in mind is that some older DVD players will choke and refuse to read anything around CBR 8,400 (I go with 8,100 to be safe)....even though max bit rate is 9,800 (video) and 10080kbps for everything (video, audio, subs)
Vence Vida February 28th, 2007, 02:20 PM Also, a "drop-out" or playback error is not bad image quality. The image was fine, it just didn't make it to the screen. That is a playback error, not compromised image quality due to dvd compression.
Andrew Kimery February 28th, 2007, 04:06 PM That's not what I was talking about. It's generally wise to make a tape back up once the NLE Master is completed. I'm suggesting that if one is having trouble making a high quality DVD copy, it might be wise to first export the NLE timeline to tape via firewire (since this step might happen anyways), than reimport the tape directly to the DVD authoring program. I'm not saying to do this on every job, but it might be worth trying if one is not happy with the DVD quality prior to trying this method.
That won't change the quality of the source footage though. Dumping to tape then re-capturing is just time wasted because the footage you are re-capuring is exactly the same as the footage you dumped off to tape.
-A
Ervin Farkas March 1st, 2007, 08:29 AM Well a dropout will only happen when your camcorder records to the tape...on the DVD you would get CRC errors...
Dropout means LOSS OF DATA regardless of the storage medium (tape, disk, card, etc). CRC refers to something related, but different: the process of DETECTING errors.
Dropout: 1. The dropping away of a flake of magnetic material from magnetic tape, leading to loss of signal. 2. A failure to properly read a binary character from data storage. This is usually caused by a defect in the storage medium or by a malfunction of the read mechanism. 3. In magnetic tape, disk, card, or drum systems, a recorded signal with an amplitude less than a predetermined percentage of a reference signal.
A cyclic redundancy check (CRC) is a type of hash function used to produce a checksum – a small, fixed number of bits – against a block of data, such as a packet of network traffic or a block of a computer file. The checksum is used to detect errors after transmission or storage. A CRC is computed and appended before transmission or storage, and verified afterwards by the recipient to confirm that no changes occurred on transit.
Source: Wikipedia.
Regards,
Alex Amira March 1st, 2007, 12:41 PM Dropout means LOSS OF DATA regardless of the storage medium (tape, disk, card, etc). CRC refers to something related, but different: the process of DETECTING errors.
Dropout: 1. The dropping away of a flake of magnetic material from magnetic tape, leading to loss of signal. 2. A failure to properly read a binary character from data storage. This is usually caused by a defect in the storage medium or by a malfunction of the read mechanism. 3. In magnetic tape, disk, card, or drum systems, a recorded signal with an amplitude less than a predetermined percentage of a reference signal.
A cyclic redundancy check (CRC) is a type of hash function used to produce a checksum – a small, fixed number of bits – against a block of data, such as a packet of network traffic or a block of a computer file. The checksum is used to detect errors after transmission or storage. A CRC is computed and appended before transmission or storage, and verified afterwards by the recipient to confirm that no changes occurred on transit.
Source: Wikipedia.
Regards,
I speak in real industry terms and the way professionals in the video industry use these terms. Dropouts most of the time are associated with tape based medium. CRC is widely used with disk based medium (hard drive platers, DVDs, CDs) etc.
You would not burn a DVD, give it to your duplication house and say "Let me know if my DVD has any dropouts".
As far as Wikipedia they just put stuff there black and white. Certain terms are used in different ways depending what industry you are in. Oh yeah...I almost forgot about Essjay, a senior member of the Wiki management team who is involved with the daily Wiki articles and changes. It seems that Essjay has been taking the Wiki concept to heart to much as he put up a lot of false info about himself in his Wiki profile (saying that he was a tenured professor with a PhD degree in theology and a degree in canon law).
SOURCE (the FORCE IS STRONG WITH THIS ONE):
Well I'm quoting straight from the NewYorker which I may add is a well known and trusted news source. I'm sure this article will be on a lot of the news outlets very soon.
LINK:
http://www.newyorker.com/fact/content/articles/060731fa_fact
TheInquirer picked this up already:
http://www.theinquirer.net/default.aspx?article=37939
Best of luck and while most articles is Wikipedia are great and accurate when a top management member lies about himself it shakes my confidence and question the whole Wikipedia system.
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