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-   -   HDV to DVD Am I Missing Something (https://www.dvinfo.net/forum/dvd-authoring/55893-hdv-dvd-am-i-missing-something.html)

Douglas Villalba December 11th, 2005 11:56 AM

HDV to DVD Am I Missing Something
 
I just finish authoring a DVD from HDV clips and it took me 16 hours to convert it to mpeg2 for DVD. I have a dual 1gig G4 w/1G ram.
Am i doing something wrong or is that the price to pay for HDV.

Dylan Pank December 11th, 2005 02:40 PM

Which software do you use and how much footage are you converting?

With a couple of hours of material, and if you're using Quicktime or Compressor, (especially with better motion estimation and dual pass) then yes, this sounds about right.

Douglas Villalba December 11th, 2005 06:33 PM

I am using compressor single pass fixed bit rate at 7 and the file was 45 min. at best stimation.
The final DVD looks better than a DV DVD, but not as good as the HDV original.

Dylan Pank December 12th, 2005 06:05 AM

I have to say that sounds slow for a dual G4 for that amount of footage, but compressor _is_ mighty sluggish.

What sort of speeds did you get when encoding DV?

Kevin Shaw December 12th, 2005 08:35 AM

That does sound awfully slow for single-pass encoding, but you should expect it to take a little longer to encode to SD MPEG2 from HDV rather than DV source. The really bad news comes when you go to encode to HD delivery formats like H.264...that will definitely be slow even on the latest computers.

Douglas Villalba December 12th, 2005 10:31 AM

The thought of getting a G5 never cross my mind until now. My friend owns a G5 dual 2.0 and I was getting about the same RT as he was on DV footage. With HDV even a 30 sec. commercial takes for ever for conforming.
What I don't understand is that HDV is already Mpeg 2, so why does it take so long to convert to different format of Mpeg 2.

Zack Birlew December 12th, 2005 10:54 AM

I know, Douglas, you'd think it would just burn instantly with no rendering required =P. I don't get HDV's MPEG-2 claim either.

Armin Obersteiner December 12th, 2005 11:21 AM

GOP is different
 
A lot of mpeg2 reencoding is taking place for a dvd gop structure:
http://patches.sonic.com/kbdocs/DVD_Parameters.htm
and for hdv:
http://www.adamwilt.com/HDV/

Douglas Villalba December 12th, 2005 11:43 AM

Do you guys know of a realtime encoding hardware solution?

Kevin Shaw December 12th, 2005 01:03 PM

Quote:

Originally Posted by Douglas Villalba
Do you guys know of a realtime encoding hardware solution?

For SD output, I get close to real-time results from HDV using my Canopus DVStorm2 card, which I just installed in my HDV editing PC this weekend. I don't know if there's anything comparable for Macs, but you might check and see if a Matrox card will work.

By the way, it makes sense that encoding from 1440x1080 HDV to 720x480 SD MPEG2 would take some processing power and time. That's almost 47 million pixels per second (times three bytes per pixel) which have to be reconfigured down to about 10 million pixels per second, and with a different pixel aspect ratio to boot. I don't know how many calculations per second of video that requires, but it's a lot.

Chris Kezelos December 14th, 2005 02:31 PM

Quote:

Originally Posted by Kevin Shaw
For SD output, I get close to real-time results from HDV using my Canopus DVStorm2 card

I've had a DVStorm2 for many years but always opted to use software MPEG2 compression over the Storm's hardware solution as I thought it yielded better results.

How do you find the Storm's MPEG2 hardware compression... and have you done a "quality" comparison against various software solutions?

I was considering selling my Storm but am interested to hear your findings. I may just reinstall it if I think it may be of use in outputting my current HDV project to DVD.

Cheers,

Chris.

Kevin Shaw December 14th, 2005 03:25 PM

Quote:

Originally Posted by Chris Kezelos
How do you find the Storm's MPEG2 hardware compression... and have you done a "quality" comparison against various software solutions?

I find the Storm's hardware encoding to be adequate for my purposes if I keep the bit rate above 5500-6000 Kbps, but not so great if you go much below that. So if you want the best quality then keep doing software encoding, but if you need to get something done quickly it's hard to beat the convenience of the DVStorm board. Plus with HDV it takes even longer to do software encoding because of the increased source data involved, so all the more reason to have a real-time encoding option.

Chris Barcellos December 14th, 2005 03:50 PM

Convert in Camera- A difference ?
 
I don't know if you have it available from your camera, but FX 1 converts in camera to DV, if you are going to use that format. Does anybody believe you lose anything down converting it in camera and then treating it as a regular DV edit and DVD render ?

Zack Birlew December 14th, 2005 06:34 PM

You don't lose anything except some HD-only detail when downconverting. It looks like regular SD 60i (if shooting 1080i), but high quality 60i SD. I can't remember if it still does 16:9 or not, I would imagine that it definitely does but I'm not too clear into specifics on that front. This would be preferable to cutting your footage up into multiple DVD's which won't even show the HD anyway unless you're using WMV HD for a PC-only viewing.

As far as the DVStorm 2 goes, I don't know exactly what to say. I would imagine the compression scheme would be the same according to your settings but I have never owned or used one before. The point of a card like that is the realtime performance and it should be good enough for DV. HDV is another story, I wouldn't use that card with it for MPEG-2 compression, I'd use software just to be safe and keep the card for some of the realtime effects features during editing.

Don't take my word for it 100%, but that's my observation.

John M Burkhart December 14th, 2005 11:46 PM

I just went through all the permutations of getting an HDV signal to a standard def DVD in Final cut studio. I'll share with you what I've found:

1. Compressor takes a long time. It just does, end of story. Hopefully apple will make some modifications to the code to speed things up. But as soon as you use any of the frame controls, your render times go through the roof.

2. Use the latest update for compressor. Before the last update, there was a bug where the field order was backwards from HDV to SD video, creating an ugly stuttering mess on playback.

3. You can burn HDV directly with no rendering! But it has to be a HD DVD project. Try a launching a new 1080i HD DVD project in DVD studio pro, and dragging an hdv clip into the project. It just plays, with no re-encoding! This will be great once everyone has an HD DVD player, but for now it's a little useless unless your customer has a mac to play it back on.

4. I did manage to burn a one hour documentary from an HDV source to SD pal. Using the 2pass 90 min preset. It took about 20 hours, but it does look very very nice.

Patience at this point I'm afraid is not a virtue, but a neccessity.

I'd be curious to see if anyone else out there has found a way to speed up workflow, by bypassing compressor...


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