long captures with Marvel G400-TV

[Enrico Ng]

I tried capturing an hour long show from TV at 704x480@30fps. I am using the beta w2k drivers and vt. It seemed to go well, and it even created several 2GB avi files.
when I went to play them, I noticed that the audio sync would be off by more with each file.
is there any way to fix this?
Should I try AVI_IO? how shouldI setit up?
I am planning on converting these videos to DiVX format.

also, I can only get about 9mb/s on my current drives. is it worth it to buy a SCSI drive? I have a scsi card that should beable to go up to 20mb/s

[Dr Mordrid]

Yes, AVI_IO is the ticket for keeping audio synch over long (or even short) captures. It's far and away more capable of this than PC-VCR or the other capture utilities.

Set it up for 29.970 frames/sec and your capture rez of choice and let it fly.

Dr. Mordrid

[Enrico Ng]

are there any settings you would suggest?
should I stilluse MJPEG?
I dont think my HD is fast enough for RGB
I need to get fullscreen.
although if RGB is that much better, I was thinking of getting a SCSI drive, 20mb/s
but I dont know what the diff is.
I'm not even sure whay YUV is.

[Dr Mordrid]

are there any settings you would suggest?

If you have the space on your hd I'd use the highest rez possible: 704x480 MJPeg at 6.6:1 MJPeg conmpression.

should I stilluse MJPEG?

Yup. Until you have enough experience under your belt to go beyond it.

I dont think my HD is fast enough for RGB

If it can't do at least 30 megs/second sequential writes it isn't fast enough to do full screen RGB (640x480).

I need to get fullscreen.

704x480 is full screen for MJPeg and YUY2; 640x480 for RGB.

although if RGB is that much better, I was thinking of getting a SCSI drive, 20mb/s
but I dont know what the diff is.

The difference between an IDE and SCSI drive right now is price. You get more for your money with a good ATA66 than you ever would with an SCSI rig.

I'm not even sure whay YUV is.

YUV (or in Marvel context: YUY2) is an uncompressed video stream that can be captured with alternative capture programs like AVI_IO (the best of the lot).

YUY2 requires at least 24 megs/second from the drive for 704x480 (20 megs/second for the basic capture and a few extra to help prevent dropped frames).

YUY2 is useful for capturing to other codecs than MJPeg and for capturing clips to which graphics and effects will be added.

The most commonly used alternative codecs are HuffYUV, MPEG-4, DivX (an MPEG-4 variant), PICVideo MJPeg (higher quality than the Marvels built in MJPEG) and raw uncompressed YUY2.

With Uleads MediaStudio Pro6 or VideoStudio4 YUY2 can be used to facilitate direct MPEG-1 and MPEG-2 captures.

Dr. Mordrid


[This message has been edited by Dr Mordrid (edited 18 June 2000).]

[Enrico Ng]

well, I'm planning on converting my captures to DiVX format.

the Hd bench says my HD can only go up to 10mb/s
I have two hds, the one I am using for video is empty.
what kind of Hd would you suggest I get to get better captures. I would assume that most would only beable to get up to 10mb/s

[Dr Mordrid]

You would be totally wrong.

The Maxtor DiamondMax Plus 40 ATA66 drives can do up to 20 megs/second even on an ATA33 interface. A 20 gig version of this series runs about $150 USD stateside.

Put two of these on a Fasttrak66 RAID controller and they'll pull over 38 megs/second and have twice the capacity of a single drive.

Fast enough for you? ;-))

Dr. Mordrid

[Enrico Ng]

whats the diff between RGB and YUV?

also, is there any "one" hd that can handle rgb or yuv?
I've heard about the raid controller.
but getting the controller AND TWO hard drives isnt really in my budget.
I do alot of video editing during summers (may-sept) but during the other times, I would just use the HD as storage.
I dont want to spend 300-500 on hard drives.
I was really just looking for 100-200.
do you know of any hard drives in that price range that have fast transfer rates? that could handle YUV or RGB?

[Joxx]

How can fasttrack66 make the HD perform twice as good compared to my on board ATA-66 controller?

How can it be that IBM GXP75 and fasttrack100 makes 68MB/s (or something)? That is faster than the maximum speed of the new U2W SCSI Seagate Cheetah X15 (15000rpm)!?

I thought that HDD was limited by other bottlenecks than the controller bandwith, am I wrong?, or how does Fasttrack100 RAID controller work?

[Enrico Ng]

its makes two HD into one so it alternates between HDs when writing, making it twice as fast. atleast thats what I think it does.

the problem is that the controller costs 100
and you need two HD

[Enrico Ng]

my MB has an Ultra-DMA/66 Controller Onboar

[Dr Mordrid]

Enrico has the Fasttrak functions pretty close. It writes to one disk then while that is being done it writes to the other disk.

With two disks the RAID doubles the effective speed over a single disk. Adding a third disk has a reduced effect, only adding about 30-40% more speed. Adding a fourth drive just adds capacity without making the array faster.

YUV/YUY2 and RGB are mathematically convertable between each other. The main advantage to YUY2 on the Marvel is that this is the format provided first, therefore requiring less overhead to use it.

Another advantage to full frame YUY2 is that is captures at 704x480. Full frame RGB captures at 640x480.

I don't know of any inexpensive drive capable of the speeds necessary for full frame RGB or YUY2. A 10,000 RPM fiber channel SCSI might be, but a 10 gigger would cost the same as 2-3 Fasttrak RAID arrays. Then you would have to spend $300-500 for the controller.

Dr. Mordrid

[Enrico Ng]

actually, I was looking at this one http://www.buyoverclocked.com/shop/P...2KEY%3A8PAR%3A
its about $60.
maybe I can just by one other Hd, and use the other one I'm using

[Enrico Ng]

do you know if the two HD have to be the same