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Andrius S.
encoding for DVD question
on Aug 8, 2005 at 3:32:28 am

Hi there. I am looking for any advice on speeding up my encoding process. I've worked with FCP a good deal, but rarely have needed to encode for DVD until now. Here's my workflow:

I'm capturing a 90 minute VHS tape in Final Cut Pro HD, adding chapter markers, exporting to a Quicktime reference movie, importing that into DVD SP3, and building and formatting to a DVD-5.

The problem is, since I'm encoding on my 1.25 ghz powerbook (2 GB RAM), the ecoding process is taking ridiculously long. I have five VHS tapes to encode like this, and since it's a favor to a friend, I would rather not tie up my laptop for the next two weeks encoding.

Is there any way of expediting the encoding so that it will take under eight hours per job? If possible, I would really like to be able to preserve the chapter markers (otherwise I think I would use toast to encode it...). Would a fast encode in compressor be recommended, or is the quality simply too low? The source is a VHS with some years on it, so the quality was not phenomenal to begin with.

Any suggestions would be great. Thanks.

-Andrius




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LukeinVT
Re: encoding for DVD question
on Aug 8, 2005 at 3:49:23 pm

Well, the rule of thumb is garbage in garbage out. If it's fairly bad quality VHS then options to speed up the encoding will ultimatly show up as artifacts in the DVD compliant mpeg-2.

Use Compressor, not Toast, not DVDSP.

Render out a 30 second QT movie that is more or less a srepresentative of the overall VHS tapes as far as quality, camera motion, color intensity, anything that will be affected by the compression.

Do a few tests at various bit rates. VBR will take longer than CBR, so if the size of the encoded file is not an issue use CBR. If you're trying to squeeze as much possible on a DVD use VBR. Try bitrates of 5,6,7 and 8 to see what the lowest bitrate you can use while still outputting acceptable video

Generally you sacrifice quality for speed. I have a feeling that if you opt for the speed over quality option, considering the source footage, you may be dissapointed with the results.

When you render out to a QT reference movie, what codec are you using?

My suggestion, find a bitrate that produces acceptable quality, set up a batch to compress a few files and sleep, go get food, just get out for a while. I like to set up a batch before I go to sleep. Hope that helps a little.


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LukeinVT
Re: encoding for DVD question
on Aug 8, 2005 at 3:51:41 pm

Also, do not worry about chapter markers, they are easy as pie to put in once you're in DVDSP


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Andrius S.
Re: encoding for DVD question
on Aug 8, 2005 at 4:54:00 pm

"Do a few tests at various bit rates. VBR will take longer than CBR, so if the size of the encoded file is not an issue use CBR. If you're trying to squeeze as much possible on a DVD use VBR. Try bitrates of 5,6,7 and 8 to see what the lowest bitrate you can use while still outputting acceptable video"

Should I then burn each test individually to a DVD to view it, or is there a simpler way of comparing my results?

-Andrius


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LukeinVT
Re: encoding for DVD question
on Aug 8, 2005 at 5:46:33 pm

Well, ideally you would have your system hooked up to a broadcast monitor. FCP 4.5 allows me to import my encoded mpeg-2's, which I can then preview on my NTSC monitor.

To do this with FCP you will need a firewire deck or camera. Run external video out via the firewire and run the signal Y/C (S-Video) out of the deck into the monitor

But, the most accurate test you will be able to do is to burn a DVD with each encode as a seperate chapter and watch them back to back (to back to back).

Do as many test encodes as you feel happy with, so you will only need to burn one DVD you can fit a whole lot of 30 second tests on 1 DVD .

Once you have acceptable encoding parameters, save your settings as a preset and use the same settings for all projects involving the same source footage


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Andrius S.
Re: encoding for DVD question
on Aug 8, 2005 at 5:57:31 pm

Okay, that's what I expected. One more question:

After encoding the video (either the tests or my final product), what should my workflow be in SP3? Do I just drop the assets in, add my chapters and then format? Or do I need to build and format still?

Thanks for your help.

-Andrius


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LukeinVT
Re: encoding for DVD question
on Aug 8, 2005 at 6:30:49 pm

Short answer, yes, after you have found suitable encoding settings and your movie looks the way you want it, drop you mpeg-2 assents into DVDSP, add chapter markers and begin authoring the DVD. At the very minimum you want to set the "first play" option. If you want the movie to start immediatly and you have no menu's, set the 1st play to track 1 chapter 1. If you have created a "main menu" where the viewer can jump to individual chapters, you can set that up as your 1st play option, or allow users to access it when they press the "menu" button on their remote control..

Long Answer, yes, you will need to build and format. Building creates the DVD files on your hard drive, formatting actually puts the files onto a DVD.

One way this is useful is if you want to test the DVD before you burn it.

Once you are happy with the DVD architecture, ie the way the viewer will interact with the menu's, chosing the scene, extras, subtitles, etc, do a test build. This will create 2 folders where you specify them, an Audio_TS and Video_TS folder. Open up Apple DVD player and chose file>open Video_TS folder and find your recently built Video_TS folder. Your DVD should open as if you just popped a DVD into your drive (you may have to hit play before anything will happen, not sure why, or of this happends on all versions of DVD player)

You can watch you DVD on your computer, test you buttons, make sure your chapters work properly. This will NOT be the time to test the quality of you encodes. By this point you should have already found a appropriate encoding preset. This is simply to make sure that your authoring is how you want it. If you find problems with the authoring, ie a button does not link to the proper chapter, reopen your DVDSP project, fix the problem and rebuild. The new build will use as much information from the previous build, making the time it takes much shorter than the initial build.

Once you are happy with the authoring, build and format a final disc, watch it on a TV just to make sure all is well, and vola.

Additionally, you can format the disc as an .img file. This compacts the entire DVD into 1 file that is easy to store and make copies from.


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Andrius S.
Re: encoding for DVD question
on Aug 9, 2005 at 9:23:53 pm

It worked great! Thanks for your help.

-Andrius


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Charles Simonson
Re: encoding for DVD question
on Aug 12, 2005 at 5:05:38 am

If your source is VHS, then encode to 352x480. That is not a typo. Trust me on this, it is the recommended way of encoding VHS quality video to MPEG-2 for DVD. Plus, at that size, you can keep your bitrates down lower and fit a lot more onto a DVD-5.

The highest quality encoder on the mac for encoding MPEG-2 is BitVice by Innobits. The fastest encoder (by far) is the MainConcpet encoder. And its quality is second best on the mac IMHO.


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Ethan Wolvek
Re: encoding for DVD question
on Sep 14, 2005 at 9:34:17 pm

8 hours to encode 90 minutes on a single processor 1.25Gh machine is not out of the realm of reality. My dual 2Gh G5 takes about 5 1/2 hours for the same amount fo footage.


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