Capturing from DV Questions!

[Zirus]

OK Basically what i'm trying to do is get a 100% uncompressed high quality video on my computer. That's possible right without any loss?

I've been reading a lot of posts and you've all scared me into encoding into mpeg2 and putting footage on dvd. So for the time being i just want "No Quality Loss Video" on my PC.

I tried using "WinDV", but its capturing into "640 by 480" (isn't DVD video supposed to be 720 by something?). Also, its an AVI file. Can a AVI file be 100% DV Quality?

Please help me out with answers and recommendations.

[edDV]

If the video is on a DV camcorder, it was compressed first by 4:1:1 YUV sampling, then 5:1 between the CCD and the tape. So that is your starting point unless you start over.

YUV, 4:1:1, 5:1 compression, 13.5 GB/hr.
AVI is just the wrapper for the DV data file. All the DV resolution is contained in the DV-AVI file. There is no further comperession.

Fully uncompressed video using CCIR-601 sample rates would be 4:4:4 YUV or RGB each sampled at 13.5MHz . That would get you 40.5 MB per second, 2.4GB per minute, 145GB per hour for 8bit per component.

Here's your capture card but it needs dual link SDI to feed RGB at 4:4:4 in serial digital. The camera might get expensive, I'll keep looking.
http://www.mediaworkstation.com/articles/viewarticle.jsp?id=29473

Here you go ... a A/D box that will capture 10 bit RGB into dual SDI to feed the capture card above. So at 10bit RGB 4:4:4 you will get approx 182GB/Hr.
http://www.ensembledesigns.com/products/serialbox/sb3.html

You still need an analog source to feed the A/D.

[FulciLives]

You can connect a digtial camcorder (be it a Digital8 or DV cam) to your computer using the FIREWIRE port (also called IEEE 1394 or i.link).

You can then transfer (yes transfer) the digital data from the camcorder to your computer. You will get an AVI file and it should be 100% the same quality as what is on the digital tape of the camcorder. It is the same quality because you are simply doing a data transfer.

A popular freeware program for doing this is DVIO but there are many other such programs.

An importnatn note ... some cams offer a USB connection. Do NOT use that. Use what is known as FIREWIRE or IEEE 1394 or i.link all is the same thing just 3 different names.

- John "FulciLives" Coleman

[redwudz]

What's your source? I assume DV camcorder. DV is AVI. Whatever DV quality your camera or DV source puts out, that is what is transferred to your computer. No capture, just transfer like copying a file from a CD to your harddrive.

If you convert to MPEG-2 for DVD, you will lose some quality because you are reducing the size of the file. You can encode with higher bitrates to get the highest quality.

[Richard_G]

What edDV says is perfectly correct, but all that happens in your camcorder before the video even gets to your DV tape. You are talking about no further loss of quality from that point on. Using Firewire, DV is transferred not captured, a simple copy of the data on the tape to your hard drive. This will be in DV .avi format, the size will be 720 x 480 (NTSC) or 720 x 576 (PAL) and the file will be 13.5GB per hour of footage.

I have no idea why WinDV seems to think it is capturing in 640 x 480, maybe it isn't but that is what it is displaying it in when you play it back. To play it back properly you will need a DV codec loaded, Most reckon the Panasonic one is pretty good. Try transferring using DVio or even Windows Movie Maker 2.

[edDV]

I've used winDV and it inputs standard DV 720x480 for me. Here is the data from a WinDV import.




Sorry for taking you literally on "uncompressed", but be carefull what you ask for.

RGB uncompressed 8 bit is 145GB per hour, 10 bit is 182GB per hour.
at CCIR-601 sample rates ~ 6.75 MHz bandwidth per component.

For HDTV this would go up considerably

So you can see the value of compression. All this can be squeezed into a 4.4GB DVD.


So recommendation for a DV camcorder, import the file with winDV or another DV import program into a DV-AVI file. Edit in DV format. Save the finished DV timeline back to DV tape for archive. Author your DVD MPeg2 at 8,000 Kbps CBR (approx 1 hr.) for best DVD quality.

[Zirus]

All this is incredibly helpful. Thanks guys.

I imported a WinDV and a DVIO capture into my video editing program & yah it said its 720 x 480. Stupid Windows Media Player, i wonder why it's saying 640 x 480. Ah well.

I'm working with a Sony TRV-38 camcorder and i'm transfering through Firewire.

I have just a few more simple questions.

1. So if i have the DV-AVI file and i edit it in a timeline and SEND BACK TO DV-TAPE there won't be any quality loss, correct? Even using things such as fading between scenes?

2. There won't be any difference in quality whatsoever if i use WinDV or DVIO right? It's just a personal preference?

3. Under the properties for Windows Media Player 9 it says its using the "DV Video Decoder" video codec. To get best displayed results on computer how can i find an updated version or a replacement codec?

Thanks once again.

[thecoalman]

1. So if i have the DV-AVI file and i edit it in a timeline and SEND BACK TO DV-TAPE there won't be any quality loss, correct? Even using things such as fading between scenes?

Yes as long as your editor encodes only the parts of the clip that you have changed.

2. There won't be any difference in quality whatsoever if i use WinDV or DVIO right? It's just a personal preference?

There's no difference no, the only difference between "capture" programs is the options. Remember your not actually capturing but transferring.

[FulciLives]

2. There won't be any difference in quality whatsoever if i use WinDV or DVIO right? It's just a personal preference?

Well that is a bit tricky.

I have heard people say that sometimes they get A/V sync issues even with a DV transfer. Now this really should NOT happen but apparently it sometimes does.

Seems to be no real rythm or reason as to why some people have an A/V sync problem with their hardware BUT when that happens it has been reported that ScenalyzerLive seems to solve the problem (i.e., DV "capture" with no A/V sync issues).

The explaination that I heard was that most DV "capture" program access something in the Windows OS in order to work whereas ScenalyzerLive does all of it's processing internally with it's own code.

One last thing to note is that when you "capture" DV you can capture to DV AVI TYPE 1 or DV AVI TYPE 2 and I believe TYPE 2 is the preferred format. However I don't work with DV much and I always forget which is which so someone else please confirm which TYPE is the preferred one. Thanks.

- John "FulciLives" Coleman

P.S.
The problem of having A/V sync trouble with a DV capture is very rare but does happen to some people and probably has something to do with a particular set of hardware circumstances etc.

[edDV]

1. If you are just cutting video, there will be no change in quality as the same data is "sent" back to the tape.

If you apply transitions (e.g. mix, wipe, effect...) those areas will be reencoded as the coalman says.

If you apply a filter to an entire scene or the complete project, such as color correction or sharpening, all the pixels will be reprocessed by the filter and reencoded to DV. Your video is at the mercy of the filter and the DV codec being used. That is why saving the DV camera originals is improtant so you can go back and start over. Many will save the project to a DV-AVI file before applying filters so they can revert to that point in the project.

[edDV]

This link explains the Type1/Type2 issue.
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/directshow/htm/type1v...pe2dvfiles.asp
It affects how audio is multiplxed. Commercial software usually uses Type2.

[Zirus]

Thanks everyone,

just my third question is the only one unanswered.

3. Under the properties for Windows Media Player 9 it says its using the "DV Video Decoder" video codec. To get best displayed results on computer how can i find an updated version or a replacement codec?

[edDV]

Same Codec my WMP 10 has.

I agree DV doesn't look good viewed in WMP. I always view DV on a TV connected to the camcoder and everything looks great there.

My editing programs Adobe Premiere and Sony Vegas 5 provide realtime monitoring over the IEEE-1394 feed to the camcoder where the internal hardware DV transcoder converts the DV stream into S-Video to the TV monitor. This is the best way to do it and the way DV is professionaly monitored. Software players just can't seem to keep up with deinterlacing a DV stream for realtime computer display. Even PowerDVD struggles..

Unfortunately, most consumer level editing programs do not provide this very desirable feature. I see that Sony left external IEEE-1394 monitoring out on the consumer version of Vegas.

http://mediasoftware.sonypictures.com/products/showproduct.asp?PID=932&FeatureID=7790&spid=280

[edDV]

There is one consumer level program that I know will playout to IEEE-1394 through the camcorder to a video monitor, Ulead Video Studio 8.

It will only stream the current project timeline, not the clips while editing or split screen filter previews like the higher end programs do. However, it is great to be able to view your timeline on a TV for quality assessment before encoding to DVD.

Credit where credit due.

[Zirus]

Thank you, if it'll look better on TV thats all that matters.

Big Thanks to everyone that replied

[FulciLives]

Thank you, if it'll look better on TV thats all that matters.

Big Thanks to everyone that replied

It is important to view on a TV if you will be attempting to adjust things like color saturation and more importantly brightness and contrast. Why? Because video looks very different on a computer screen than on a TV screen when it comes to such picture properties as brightness and contrast etc.

This is definately true of NTSC video ... may not be as big a deal with PAL video.

- John "FulciLives" Coleman