Yet another blasted DVD Authoring Question :) (1 Viewer)

[DeathStar1]

OK, here's something I've been wondering.

I'm assuming we get the same discs the proffesionals use. So, how is it companies like Paramount can fit 4 hours of high quality TNG on to one disc, yet I can only fit an hour of high quality stuff onto mine?

Is there some type of compression that I'm not setting up properly, or am I being kept out on the loop of something?

Thanks!

 

[Jeff Kleist]

I'm assuming we get the same discs the proffesionals use.
So, how is it companies like Paramount can fit 4 hours of high quality TNG on to one disc, yet I can only fit an hour of high quality stuff onto mine?

Because you have a single layer disc and thye have a double layer for starters, which in the authoring stage is done as 2 seperate checkdiscs. Double layer DVD-Rs are not likely to show up anytime soon, especially with DVD encryption being cracked as it is. Also, professional DVD-Rs can write to the copy protection and encryption sectors of the disc, and they run about $30 a disc

I don't know what kind of compression you're using either. Are you doing computer or standalone deck compression? Professional DVD is done in multipass Variable bitrate to allow the most information to fit on a disc by not wasting bits where they aren't needed.

This should probably be in computers

 

[Vince Maskeeper]

As Jeff said, the big difference is layers. Home recordable DVD is Single Sided and Single layered, giving you about 4 gigs of data space. 4 gigs is just enough for right about 2 hours of decent quality MPEG video.
A replicated disc from a professional company are often dual layered, which is closer to 8 gigs, giving about 4 hours of decent video.
Understand that MPEG compression (as I've said nearly a million times around here) is more an ART than a science. Professional authoring is not like making an MP3: just select a bitrate an go. Professional compressionists utilize VBR compression, down to the frame level. Often a quality compression job for a DVD master will take weeks to tweak the best quality to data ratio- as certain scenes compress better than others.
How are you doing compression? What program, settings and format are you using? Are you using a Mac? If I recall, some early Mac DVD software limited you to 1 hour regardless...
See also:
http://www.hometheaterforum.com/htfo...threadid=81229
-Vince

 

[Wayne Bundrick]

The quality of the source material is also a factor. The studios start by transferring the movie from film to D-1, an uncompressed format with the same resolution as DVD (or they transfer film to high definition and then scale it down to D-1). High quality, noise-free video at the start will yield better results when compressing it to MPEG2. If you're transferring a VHS tape to DVD-R, it simply isn't possible for the DVD-R to look better than the VHS tape.

And, the studios are using top quality MPEG2 encoders. As Vince said, they do multipass compression, and then they go back and hand-tweak difficult scenes. This will always yield better results than the on-the-fly realtime compression that would be done by a standalone DVD recording deck, or a multichannel service such as digital cable, DirecTV, etc.

Anyway, I've had very good results using TMPGenc multipass encoding to fit 2 hours on a single layer.

 

[DeathStar1]

Hm, OK. It was obvious that movie industries have better equipment than we at home do, but I was just wondering if the same type of disc and compression is used. Also, I wasn't complaining about trying to get a better picture than the original VHS, just trying to fit more than one hour of quality video on a disc ..
>How are you doing compression? What program, settings and format are you using? Are you using a Mac? If I recall, some early Mac DVD software limited you to 1 hour regardless...>>
Here's me specs...
Pentium 3 1GHZ
100GB 8MB Cache Hard Drive
ATI All in Wonder 64MBDDR TV Tuner.
I've been using their DVD High, and DVD Medium Settings.
DVD High: 720X480 NTSC(525) 8.000 M B/second 48KHZ 16 BitS
DVD Medium: 352X480 NTSC 3.00 MB/second, 48KHZ 16bit Stereo.
With the former, I can just BARLEY fit about 1 hour of high quality video onto a disc, and with the latter, usually two hours and twenty minutes. With their DVD Low, I can sometimes squeeze in an even four hours, but with obvious pixilation evident.
Also using My Sonic DVD wich came with the HP DVD Writer.

 

[Jeff Kleist]

Try setting your bitrate down to 5-6 Mbps

You'll also do a lot better by registering TMPEG, which is fairly cheap and using multipass VBR. Should be able to get about 90-100min with decent quality that way

Going VBR I have had good success setting the floor at 4Mbps and the ceiling at 8Mbps

 

[Drew Dockery]

While we're on the topic, can someone point me to a good site that covers different authoring software and perhaps some how-to's? I'm planning on buying a DVD burner and video capture device soon, and know nothing about it.