Preparing for replication

[Peter Dunphy]

Hi Guys

This is my first time about-to-deal with a replication house. Any thoughts on my 'workflow' below would be really appreciated to produce SD DVDs.

I would like to create the best possible DDP image file possible, for the replication house.

1. Is it an .img file I should be outputting from DVDSP to give to the replication house on a pen drive?

The video contains lots of fast moving, fast edited sports sequences. The original format is Canon XHA1 HDV 1080i PAL (recorded at 50i to play at standard PAL 25fps on VCRs).

The HDV was captured into FCP as standard ProRes422 and edited and rendered entirely in standard ProRes422 and output from FCP as a standard ProRes 422 1920 x 1080 QT File.

Using BitrateCalc I entered 46:33 into Video Length, and selected Type: DVD

2. For DVD I selected 1 x 4.37 DVD5 (am not sure of the capacity of the DVD discs the replication house will be using but 4.37 is pretty common isn't it?

3. Should I maybe ask the replication house what capacity DVD discs they intend to use, and then return to BitrateCalc with my findings?

4. Anyway, with 4.37 DVD5 selected the results are:

Calculated bitrate: 9576 kbit/s
Authoring overhead (2%): 90 MBx
Estimated audio size: 77 MBs
Estimated vide size: 4399 MBs
Estimated size on disc: 4566 M

How might I interpret these figures?

5. Should I also maybe choose a GOP structure setting (Open/Closed, IBBP, IP, IBP, GOP Size)?

As regards a Bitrate Viewer I plan to use this free one (for Mac):

MacDVDBitrateParanoia - Video software and downloads - VideoHelp.com

Again, any thoughts whatsoever would be really appreciated.

Warm regards

Peter

[Shaun Roemich]

I might be wrong but I believe your bitrate is too high for playback reliably on set top devices.

[Peter Dunphy]

Hi Shaun

Thanks for posting.

Yeah, I mean, I could set a maximum bitrate of 7.4 for safety but was wondering whether a higher bitrate could be used for a .img file to be given to a replication house, so they can produce a glass master etc.

Was thinking of asking the replication house directly but just wanted to be armed with some info should anything go wrong down the line at their end.

I'm a bit concerned also that despite using a max bitrate (say, 7.4) in Compressor it can still sometimes spike above that.

[Seth Bloombaum]

Originally Posted by Peter Dunphy

... could set a maximum bitrate of 7.4 for safety but was wondering whether a higher bitrate could be used for a .img file to be given to a replication house, so they can produce a glass master etc.

Was thinking of asking the replication house directly but just wanted to be armed with some info should anything go wrong down the line at their end.

I'm a bit concerned also that despite using a max bitrate (say, 7.4) in Compressor it can still sometimes spike above that.

A max bitrate of 8.0Mbps is safe for DVD-R, the replication house may say you can go a bit higher. 9.5 is per the set-top hardware spec, however, as Shaun says, experience has shown that 9.5 is much too high with commonly available hardware.

An .img file would have a 1:1 relationship to a glass master, which would have a 1:1 relationship to a pressed disk. If you're doing the authoring and encoding, it's up to you, not the replication house, to manage bitrate. Don't put any more in than you want on a pressed DVD.

You should get a complete set of specs from the rep. house, which will include their delivery specs. Those specs vary between different facilities. If it's difficult for you to produce to the delivery spec of the disc manufacturer, look at others, they'll be different.

I'm not that familiar with Compressor producing a VBR with a max bitrate of 7.4 that spikes above 7.4. If this is true, you'll need to do a very careful evaluation of the resulting MPEG2 file.

Some replication houses offer authoring and encoding services, this is another method for getting what you want... some hardware encoders are superior to our sw tools.

You should definitely burn some DVD-R of your authored project, and test on various set-top players before sending off for replication. If you're doing the encode, it's you, and only you, who has control of picture quality, there is no "...should anything go wrong down the line at their end" with regard to picture quality.

Sorry if this sounds harsh - better now than binning a run of 1000 DVDs. That is a harsh experience best avoided.

[Peter Dunphy]

Hi Seth

Sorry for the long delay in replying to your excellent post - I hadn't been on the forum in months.

"An .img file would have a 1:1 relationship to a glass master, which would have a 1:1 relationship to a pressed disk. If you're doing the authoring and encoding, it's up to you, not the replication house, to manage bitrate. Don't put any more in than you want on a pressed DVD."

This is really brilliant advice. I'll re-post in this thread my experience with the replication house.

For safety, I will ask the replication house to encode and author this particular big video project I've done. I have DVD Studio Pro but just want to play absolutely safe with this video.

Like you say, a batch of 1000 DVDs that don't play properly would be a catastrophe!

How does this sound...

I plan to ask the replication house to encode and author the video, in addition to running off the discs. I will ask for their specs and delivery specs. Then, based on the specs, I will bring my self-contained Quicktime movie (the QT file that can be exported directly from the FCP timeline) on an external hard drive to them, and let them copy it onto their computer.

I will also give them a Quicktime file of a video I want to play in the background of the main menu. I will give them details of what kind of buttons I want and what the buttons should say, and the transition into the movie beginning once the viewer presses play.

...it would be nice to have created the menu and do the encoding and authoring myself, but since the video project I've finished is very important, it's best to have the replication house 'take charge' of it I feel. Also, it's like a security, so if there are any problems with the finished DVDs, I can't be blamed for not encoding properly, because I was not responsible for it.

What do you think?

Thanks for your terrific feedback.

Peter