Recording ntsc directly to a dvd recordable drive using aiw 8500dv (1 Viewer)

[peter m. wilson]

Hi,
Is this possible or do you have to record to the hrd drv first and then transfer to dvd?

Peter m.

 

[Ken Chan]

No, you have to go through an authoring step. DVDs aren't just MPEG files on a disc, they're organized in a particular way. You couldn't take the disc and play it on a plain old DVD player. It should eventually be possible (with newer DVD drives and video cards or software) though.

//Ken

 

[peter m. wilson]

Hi Ken,
And thanks for your response.
I got the idea because of the Sony Mavica camcorder that will accept wahtever your filming directly onto a dvd disc so I thought if you had a good vid card, a fast processor and a fast dvd recording drive you could do the same thing that table top boxes or these camcorders are doing.

So what do you think the minimum reqirements of your box and dvd recorder would be to all of this.

Peter m.

 

[Ken Chan]

I would guess that the Sony has dedicated hardware to make that happen. Plus you won't have a lot of flexibility with the menus and such, unless you were using an RW disc that you could modify.

The DVD drive wouldn't have to be that fast, it only has to record in real-time. You would want hardware MPEG encoding, and the ATI has at least some form of hardware assist, since it can capture to MPEG. You'd also want hardware assist for AC-3 encoding (plain old PCM takes up way to much space), but you could probably get by with software. Not sure how much horsepower it would take to multiplex the video and audio, which it would also have to do live. When you do that when authoring, it takes a while, but as I recall it's mostly because of all the reading and writing of the drive; the CPU isn't that busy. If you are recording live, that would all have to be done in memory (unless you had some fallback buffering to disk mechanism).

Just speculating, but with current high-end hardware, including hardware MPEG encoding, you might be able to do it now if someone wrote such a program. There may be issues with lead-in and lead-out times (the time it takes to initialize the disc before starting to burn, and the time it takes to finalize it when done) so you can't start and stop on a dime. (This is an area with the +R/RW is supposed to have an advantage over the -R/RW.) So if you want to record from 8 to 9, the drive might have to spin up at 7:59 and the disc wouldn't be done until 9:02 or something.

//Ken

 

[peter m. wilson]

Hi Ken,
I really wouldn't care too much about the finess of it all becuse i have no intention of archiving what I record (just some weekend afternoon golf matches that i watch when i get home from playing) so DVD RAM would probably be my choice and I would just use the time to start and time to finish recording options rather than Guide + or anything like that.

I would be happy just using the hard drive but I use a PCI video scaler that works with outboard dvd players, so i was going to use my sdi modded Panny rp82 to play the ram disc at whatever rez would fit on the disc and then send it through my HOLO3D scaler at 1080i and out to my hdtv.

It's probably much less complicated to get a set top box dvd recorder but whats the fun of that.

I'm just curious if anyone with an ATI AIW card and a dvd burner had tried the pvr feature that way and what the results were.

I have a P4 2gig with 512 megs which is probably borderline. I guess I could checkout the software with my cd writable drive just to see if it would accept the command from the ATI card because if I remeber correctly it's only options right now are a fat32 or the other one (can't remember what it's called).

I remember a couple of years ago when i recorded the drive had a 2gig limit forced by windows so I would figure out how much record time i needed for 2 gigs and repeated the command with 1 minite breaks so i would get 3 files of 1 7/8gigs that would run concurrently when I pressed play.

Talk about making it tough on myself, but beieve it or not at the best record type the PQ was much better than a vcr PQ on a 65" set and it impressed the hell out of my friends.

thanks for your comments.
Peter m.