DV to Harddisk without compression

[anarco]

I don´t know if this is silly, I found some articles telling how to do a Live DV recording to DivX directly.

But I wonder if it is possible to capture from a DV Camcorder directly through firewire into a huffyuv or even uncompressed avi.

I know this would require a transfer of ~ 40 MB/s.
However, lets say the machine and cable are fast enough.
I think it still is impossible to turn off the DV compression within the camcorder - or ?

anarco

[jkwarras]

Originally posted by anarco
But I wonder if it is possible to capture from a DV Camcorder directly through firewire into a huffyuv or even uncompressed avi.

I think there's a way, but not with application like premiere or similar NLE software. You can capture through wahtever codec you want for ex. wth Media Player Classic. Just do File>open device and then choose your DVcam as input. There you wil have options for Audio and video (codec compression). As your capturing via firewire BUT via Directshow (that's what i've undesrtood, but not quite sure), audio will not be captured, you can either capture it later as usual or plug your DVcam audio output to your soundcard input. So:

- Capture video via firewire
- Capture audio via soundcard

You need a fast machine.

I think it still is impossible to turn off the DV compression within the camcorder - or ?

I will love to know that but i don't think is usefull because DV is a lossy format, and the image in DV tape is already compressed.

But if this was possible, maybe you'll be able yo hack it in order to capture higher formats (DigiBeta for ex.) through a cheap firewire :)

anarco

[bb]

Your source is DV, so why would you want to convert to Huffyuv or uncompressed AVI in the firewire recording step? The quality won't get better, because all you do is to "blow up" the already compressed source.

bb

[anarco]

@bb

I don´t want to recompress it I want to override the the DV codec.

the function of the camcorder should be smth like

optic -> codec -> tape

I want to capture it directly after the optic ;-)

I have no clue about the tech of a camcorder so I can´t tell if it is possible to grab the videosignal before the compression.
Thats just an insane idea.

anarco

[jkwarras]

Originally posted by anarco

optic -> codec -> tape

I want to capture it directly after the optic ;-)


You can do it as with the method i post before. Maybe you're right and you can get better image quality on-the-fly capturing. For ex. i know that DVcamPRO use 50Mbps/s (DV is 25Mbps/s) and you can capture it via firewire.

Hint: If your DVcam allows photo still mode, switch to this and capture via firewire as it use:

- Progressive
- Full resolution (1028 x XXX: depending on your DVcam model)

[AudioVideoMaster]

Originally posted by jkwarras
Hint: If your DVcam allows photo still mode, switch to this and capture via firewire as it use:

- Progressive
- Full resolution (1028 x XXX: depending on your DVcam model)

I've tried that a couple times with pretty good success. Keeps the frames from interlacing. And I've done it inside of Premiere I think, can't remember that since it's been a while. The only thing is that you have to be hooked up the computer the whole time unless you had a fast fast laptop you could use on location. My dv cam is a consumer model Panasonic.

[jkwarras]

Originally posted by AudioVideoMaster
I've tried that a couple times with pretty good success. Keeps the frames from interlacing. And I've done it inside of Premiere I think, can't remember that since it's been a while.

I've also done it, but not into premiere because you have to capture to DV, and i think that it only allows 720x576 (PAL) max resolution (maybe i'm wrong).

I've tried via Media PLayer Classic, compressed losless with HuffYUV at 1280 x XXX resolution (sound via soundcard). Looks very very good. MOre "Film look", and progressive.


The only thing is that you have to be hooked up the computer the whole time unless you had a fast fast laptop you could use on location. [/B]

Yes, that's the thing. To use it you can either:

- Stay connected to a computer (risk of dropped frames if not a fast system, and obvously it has to be laptop to be able to shoot outside)
- Connect your DVcam to a DV HD (i think this is expensive). I don't know if there's a way to connect via firewire a normal HD without all the OS and monitor, blabla. I guess you always need an OS (and power supply) to make it work.

[anarco]

ok tried premiere but it doesn´t allow me to change the settings
it just gives me the DV option with compression on

gotta find a firewire capture program that supports different codecs

[jkwarras]

Originally posted by anarco

gotta find a firewire capture program that supports different codecs

You can't. Firewire aims to transfer video to HD without capturing and compressing. It's designed to work with DV codecs: standard DV (25Mbps) and with some special hardware cards you can use another codecs like MPEG-2 and DVcamPRo (50mbps), which work with standard resolution as 720x576 (PAL) and 720x480 (NTSC i think).

So, in order to use firewire to capture into another format than DV, you need to use it as DirectShow, so you'll be able to change compression codec (and for ex. choose HUffyuv, XviD, uncompressed, whatever...) and resolution settings (be careful because every codec has is own restrictions in terms of resolutions). I would recommend you Hufyuv as i think as no restrictions and is lossless (but files will turn very big). Sound will not be captured via firewire. You need the soudncard for that.

Programs that allow that:

- Media player Classic
- VirtualVCR
- VirtualDub (i think)

But don't use any DV capture software as is not based on directshow but in VFW (am i wrong?) and you have to stick to the DV codec.

[anarco]

Yes, technically firewire is just an interface as usb or bluetooth is
so this actually should just be a matter of software as you say.

I don´t care about the filesize (yet).
For speed it is probably best to capture to plain raw. I don´t want any lossy compression so the other choice would be huffyuv.

Btw the reason for this insanity is that I converted some DV Material to DVD and watched it with a beamer.

There is probably a lot of improvement possible I am not gone deeper into the conversion subject, I just used procoder with mastering quality - but that just look NOT GOOD. I want it to look like almost DVD quality not like VCD ;)

And in case I want to create a little movie I want the best base-material I can get for the additional money I want to spend ( none ;) ).
If there is a way to get the progressive photoshoot work as video source - why not.

[vhelp]

.
.
No effence to anyone here :)

But, this is nonsense. You can't go (for example) from:

TRV-22 --> DV Chip --> Tape or Hard Drive

..to

TRV-22 --> Tape or Hard Drive


Even if you Firewire (FW) it directly (while connected, or aka,
Live) you can't by-pass your CAM's DV chip. Somebody must be confused
here :eek:

Also, why would anyone want to take their DV (which, again as ben stated
as lossy)
and convert it to another codec.
.
.
About the only time such steps would be taken, is if for instance,
you had to perform some tests on codecs and things, or wanted to use
a codec that produces an even smaller file size, or had to use it due
to sofware issues or requirements.

If you want to get a different quality from your DV cam footage other
than your DV's codec (or chip) then you have to either:

* Get another DV cam, and pass the S-Video from your first cam, and
into your 2nd cam for recording (quality will be slitely different)

* Using your first cams S-Video out, you capture from it to ANY codec
of your choice.

Note 1, FW'ing your DV to your HD (aka, Live) will not alter your DV. It
will STILL be DV codec'sized, though you SW app can pass it through
another codec, as I believe is what was going on in the above posts.

Note 2, If you S-Video from your first cam, into your 2nd cam, your
2nd cam will be DV'ing it w/ it's DV chip. But, because the video
source is slitely different, it may be slitely off per user's eyes.

Note 3, AFAIK, S-Video from a cam doesn't get DV-codec'sized, when
going out to a pc's Video In for capturing. This I tests, because
the color space is deffinately off and there are not DV macro blocks
(when magnified) So, S-Video (per my TRV-22) is deff. Live.

What would really be great is if someone could come up w/ a
digitized way to get the S-Video output to a storage device, w/out
every using any lozzy codec. I'm sure it's possible. And, I'd sure
give it a try if I knew how.


@ jkwarras

You can do it as with the method i post before. Maybe you're right and you can get better image quality on-the-fly capturing. For ex. i know that DVcamPRO use 50Mbps/s (DV is 25Mbps/s) and you can capture it via firewire.

Hint: If your DVcam allows photo still mode, switch to this and capture via firewire as it use:

Quesiton, what's this talk about "photo still mode" and no interlace ??

-vhelp

[SiliconSoul]

This biggest overlooked issue here is the Quality of the DVcam? is it a professional camera? If it is a consumer camera that it was shoot with that is your problem. Not how it is getting to the HD.

Your source is DV, so why would you want to convert to Huffyuv or uncompressed AVI in the firewire recording step? The quality won't get better, because all you do is to "blow up" the already compressed source.
bb


The recorded source on the tape will not get any better by taking it off a different way and thats another problem is that when you use the DVcam it still goes out the DV chip in the camera.

There is probably a lot of improvement possible I am not gone deeper into the conversion subject



NONE unless you get a better camera and RESHOOT the material
If you want better Results then i suggest a better camera to SHOOT the material in the first place. Your not going to get much done beside wasting tons of time.

I just used procoder with mastering quality - but that just look NOT GOOD. I want it to look like almost DVD quality not like VCD

well maybe you need to use some filters...

[anarco]

Even if you Firewire (FW) it directly (while connected, or aka,
Live) you can't by-pass your CAM's DV chip. Somebody must be confused
here :eek:


Thats what the cam-producer would say
same as you don´t have a DV-in on most european camcorders (Though you can "hack" THIS feature.)

If you have a signal you can also grab it before the DV chip.
It might require advanced knowledge about the camcorder but technically it has to be possible.


Also, why would anyone want to take their DV (which, again as ben stated as lossy) and convert it to another codec.


never wanted that - I´d just use huffyuv which is lossless to save some space


* Using your first cams S-Video out, you capture from it to ANY codec
of your choice.


Thats pointless until the S-Video out grabs the signal before the DV-Chip.


Note 1, FW'ing your DV to your HD (aka, Live) will not alter your DV. It
will STILL be DV codec'sized, though you SW app can pass it through
another codec, as I believe is what was going on in the above posts.


Thats clear. The question actually is, can I get the camcorder capture lossless to the pc (not the stuff from tape)


Note 3, AFAIK, S-Video from a cam doesn't get DV-codec'sized, when
going out to a pc's Video In for capturing. This I tests, because
the color space is deffinately off and there are not DV macro blocks
(when magnified) So, S-Video (per my TRV-22) is deff. Live.

What would really be great is if someone could come up w/ a
digitized way to get the S-Video output to a storage device, w/out
every using any lozzy codec. I'm sure it's possible. And, I'd sure
give it a try if I knew how.


That is the big question. If S-Video is taken before the DV Chip then its quality is definately better than the stuff that ends up on your tape.

Another way would be to use the progressive photoshoot function.
If you can get that out of the camcorder and is fast enough
you might even be possible to capture 25fps in 1024x768 without interlacing. Maybe this could even be passed through the Bluetooth interface. Tough I have doubts that it is fast enough.


anarco

[jkwarras]

Originally posted by vhelp
Even if you Firewire (FW) it directly (while connected, or aka,
Live) you can't by-pass your CAM's DV chip. Somebody must be confused
here :eek:

It makes sens to me. I was assuming that capturing directly from Dv to PC (no intermediary step from DV tape) would not use DV chip compression. Anyway i'm going to do some test about it and post results.

Quesiton, what's this talk about "photo still mode" and no interlace ??

I'm talking about using the photo mode most DV camera have, that use ALL the pixels and ALL the resolution. AS you may know most MiniDV cams that feature 1.5MB pixels (for ex. my SOny PC120) don't really use all this pixels in normal video mode. Instead it use full resoution (1028 x 768) and the 1.5MB pixels in photo mode. This mode is progressive, since video shooting is not (interlaced). So you have a pure 25fps shooting if you can get directly the image you get in photo mode into your PC (you can't tape this, the only other posible way is to connect your cam to another cam and tape the image, but again you're losing information since the image will be tape into DV and interlace).


@SiliconSoul:

There's a lot of improvements you can do, even with a comsumer DV cam. OF COURSE you get better quality with a Better Cam, no doubt about it :p BUt the point is try to improve the quality of your shooting without spending more money. What we say makes sens if the image is not passed trought the DV-chip before going into the PC, if it's passed then there's no point, that's true. As vhelp point out, if S-Video is not passed through DV-chip THEN you're improving quality. BUt aren't S-Video less quality than firewired DV footage?

[bb]

To pick up the S-Video signal makes no sense to me, because it's an analogue output, and the quality will be worse than the DV readout through firewire (even if captured losslessly).

You'd need to get the digital readout from the CCD before it gets into the D/A converter. I don't believe that this is easily possible. The progressive digital image capture "misused" for moving pictures has been discussed before, and if you can do that with your camcorder model, then it's the only alternative to the classic way I can imagine.

bb

[SiliconSoul]

never wanted that - I´d just use huffyuv which is lossless to save some space

How are you saving space?
DV is compressed and Huffyuv is not

what you are trying to do is get better quality out of the camera...
correct?

The quality you have on the tape is MORE determined by the Quality of the camera you used to SHOOT the footage.

It makes sens to me. I was assuming that capturing directly from Dv to PC (no intermediary step from DV tape) would not use DV chip compression. Anyway i'm going to do some test about it and post results.

The Camera SAVES the video on the Tape using the DV chip. So it has to use the DV chip to output the footage... no matter if you go out firewire or S-Video.
Basicly when you use firewire to capture the DV to the Hard Drive you are getting the same quality that is saved on the tape. The Video is Compressed by the camera on the Tape. Then output to the FW still compressed.

its the same theory as trying to reencode Crappy video

Garbage in Garbage out.

bascily get a better camera and reshoot
or filter... you would be surprised at what good filtering can do to the quality of the video.

also i would like a screen shot of the same frame. one from the DV and then one from the DVD.


with procoder... are you sure you used the DVD template? not the VCD one?

could the problem be the monitor your viewing it on?

have you watched it on any other TV? does it look better there?

does the original DV on the HD look better than the DVD?
this could be your biggest loss of quality...


What camera are you using?

[SiliconSoul]

DV camcorders actually record video on their tapes in a digital compressed format. Most of these DV camcorders have a serial port that supports an IEEE standard called IEEE 1394

Using FireWire, you can download a copy of video from your digital camcorder into your computer without using a framegrabber. The advantage is that the video on your hard drive has the same quality as the video in your camera.

this article is talking about framegrabbing but hits some main points...

http://www.bw-software.com/tdvwork.html

[anarco]

Originally posted by SiliconSoul
How are you saving space?
DV is compressed and Huffyuv is not


*sigh* I don´t want DV encoded stream from the cam I want plain raw stream from the cam and encoding plain raw with huffyuv would indeed save ~20% space.


what you are trying to do is get better quality out of the camera...
correct?

The quality you have on the tape is MORE determined by the Quality of the camera you used to SHOOT the footage.


I don´t want to get anything from tape. Forget about the tape, my gain is to directly get the stream just like from a webcam.


The Camera SAVES the video on the Tape using the DV chip. So it has to use the DV chip to output the footage... no matter if you go out firewire or S-Video.


I don´t give a flyin´what happens on the tape ;)
Of couse the cam requires to use the DV codec to fit the stuff on tape otherwise the tape needs to move faster or needs more space to store the data.

But I don´t care about the tape in the cam.
I want this: Optic -> Firewire -> PC.


Basicly when you use firewire to capture the DV to the Hard Drive you are getting the same quality that is saved on the tape. The Video is Compressed by the camera on the Tape. Then output to the FW still compressed.


Yes but I don´t want it to be on tape and in fact the cam just needs the DV codec to fit the data on the small tapes, not for speed or anything else.


its the same theory as trying to reencode Crappy video
Garbage in Garbage out.


I never wanted to reencode DV encoded stuff. I know thats pointless unless you want it get worse or smaller.


bascily get a better camera and reshoot


Thats the most expensive and easiest way .. true ;)

The NV-MX8 got a pretty excellent leica optic - in my eyes the electronic behind that optic is just not good enough for the optic.


or filter... you would be surprised at what good filtering can do to the quality of the video.


Thats another way of course and since I haven´t tried
too many different settings yet so there may be possible improvements.

However the DVD I did look fine on TV but I personally use a beamer
and there you see alot of fragments.


also i would like a screen shot of the same frame. one from the DV and then one from the DVD.


Yep will get them when I have some more time... I first need to check the look of DV on a beamer. If that looks much better the encoding to DVD just was crap.


with procoder... are you sure you used the DVD template? not the VCD one?


erghm... me no stupid ;)


could the problem be the monitor your viewing it on?


beamer


have you watched it on any other TV? does it look better there?


it looks better on TV than on a beamer of course... simply because you can´t see the pixels on a TV


does the original DV on the HD look better than the DVD?


yes


this could be your biggest loss of quality...


It is for sure but thats not the main question.
If I can (in any possible way) get an uncompressed stream from the cam
why shouldn´t I use it?
Encoding any movie from uncompressed, maybe even progressive material will always be better than using DV as source.
And as I mentioned above, the NV-MX8 got an excellent optic, I want to get the max out of it.

[vhelp]

@ anarco,


I don´t give a flyin´what happens on the tape
Of couse the cam requires to use the DV codec to fit the stuff on tape otherwise the tape needs to move faster or needs more space to store the data.
But I don´t care about the tape in the cam. I want this: Optic -> Firewire -> PC.

Believe me you, I understand your point :)
.
.
But, here's something to think about. What if the footage being
recorded to tape doesn't actually get DV'd ?? ..and just gets
recorded to tape ??
.
.
Then, what if you used your S-Video and Analog captured it to a lossless
codec ?? ..Sounds crazy, but I'm working on this now - testing..
.
.
Otherwise, all we could be in wrong, and what gets recorded to tape
is DV'd.

But, my point here (above) is like this. Say, what you shoot and record
to tape get DV'd to tape. Now, you go and FW it to your hd. Does it
get re-DV'd again a 2nd time around ?? :eek:
Hmm... interesting.. ain't it ??
.
.
Lets assume that whatever we record to tape, is NOT DV'd.
And, give S-Video and Analog capture a shot, and see for yourlself :eek:
.
.
I mean, it doesn't make sense to DV something twice, does it ??
Unless the tape mechaninsm/circuitry says, "hold on.., we've ben DV'atized
and don't need to be a 2nd time. ..that's if it get DV'd during the
recording process.

My point about S-Video is that it's plain vanilla. No DV artifacts that
I can see based on my experiments thus far. Even Composite (RCA) looks
grate on TV sets.
.
.
I think that what's really needed here is a GOOD codec
to extract the S-Video source via an Analog capture card. Forget about
the DV. After all, we'er all looking for "plain vanilla" output to
manipulate, but w/out the side-effects that accompany DV (we all know
what they are)

Well, some more things to ponder about :)
-vhelp

[SomeJoe]

anarco,

You're not going to achieve what you want with a consumer camcorder. There is no way to capture the uncompressed data from inside the camcorder unless you were to hack the camcorder, do some severe electronics engineering, and build a custom interface.

The camera takes uncompressed RGB directly off the CCD and delivers it to the DV encoder chip. The compressed DV digital data comes out of that chip and is then delivered to the tape writing circuitry or delivered to the 1394 interface chip which encapsulates the DV data for transport.

You would have to build a custom circuit that would take the uncompressed RGB off the CCD, packetize it, and then deliver it over firewire. The data rate you're dealing with for uncompressed RGB is about 250 Mbps. Portions of your circuitry would be operating at 250 MHz or above. Those clock speeds require major CAD systems to design, as tenths of an inch differences in trace lengths on the circuit board can cause interference.

Now, for an actual practical solution:

If you want uncompressed capture, you don't want DV. You want D1. D1 cameras are uncompressed 8-bit YUV data delivered directly to the NLE editing system. Canon and AVID will set you up with such a system for multi-thousands of dollars. :eek: But it is possible.

[SiliconSoul]

so just to be sure you are confirming what i was saying in the first place... that it goes thru the DV chip no matter if it goes to tape or pass thru?

thus there is no way to get uncompressed DV from a camera. as it is all compressed no matter what.

[anarco]

@vhelp, the stuff on Tape is definately DV´ed and it won´t get DV´ed again when doing tape -> firewire

But this actually is a good point cause it on the other hand also says there is also a stream which doesn´t get compressed again.

@SomeJoe
250MB/s hmm I think this depends on how many fps actually get delivered. That limitation is probably done by the DV circuit as well.
If not - 25fps wouldn´t take mor than 50 MB/s (depending on how the audio is captured but that should be done seperately with a mixer / ext. mic anyway).

D1... I know there is stuff that does the job but that doesn´t help.
With money you can get everything, thats not the point.

[SiliconSoul]

this is a lost cause the whole point of (mini)DV cameras is to compress the video. Your not going to undo that in any way. what you need is another digital transfer device because a DV camera is not going to let you do what you want it to without changing the hardware.