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Is there zero video quality loss using a firewire connecti..

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December 23, 2004 4:46:51 PM

Archived from groups: rec.video.desktop (More info?)

My DVD Recorder has a firewire DV In/Out connection.
If I transfer video from the DVD Recorders hard drive to the computers
hard drive using the firewire connection is there any loss in video
quality?
The reason to transfer video is to do more editing on the computer
such as adding fades etc.

Regards Brian
Anonymous
December 23, 2004 4:46:52 PM

Archived from groups: rec.video.desktop (More info?)

Brian <bclark@es.co.nz> wrote:

>My DVD Recorder has a firewire DV In/Out connection.
>If I transfer video from the DVD Recorders hard drive to the computers
>hard drive using the firewire connection is there any loss in video
>quality?
>The reason to transfer video is to do more editing on the computer
>such as adding fades etc.
>
>Regards Brian

Haven't heard of a DVD with Firewire but as Firewire is simply a data
transfer there will be no quality loss.

(How the hell it converts an mpeg stream to a DV stream is beyond me
though).

Cheers


--
Kevin Gleeson
Blue Rocket Productions
www.blue-rocket.com.au
www.hoota-snoz.com
Anonymous
December 23, 2004 4:46:52 PM

Archived from groups: rec.video.desktop (More info?)

"Brian" <bclark@es.co.nz> wrote in message
news:o 65ks09rnnovp2eik00mhui8pf7dnv883q@4ax.com...
> My DVD Recorder has a firewire DV In/Out connection.
> If I transfer video from the DVD Recorders hard drive to the computers
> hard drive using the firewire connection is there any loss in video
> quality?
> The reason to transfer video is to do more editing on the computer
> such as adding fades etc.
>
> Regards Brian
>

The firewire transfer itself should be lossless (error free), however,
what you are transferring may be more of a problem. If the video
you are transferring is already converted to MPEG2, that is hard
to edit without further losses due to recompressing. Firewire in
and of itself is just a digital "pipe" between systems (I have an 80 gig
hard drive in a stand alone case that also plugs into the firewire
port and just looks like another drive -- use it for backups). You
need to see what is being transferred across from your recorder.
From camcorders, it is usually DV format which is compressed, but
lends itself to editing well. The more compressed the data is you
transfer the harder it is to edit without more losses (this is independant
of whether you got the mpeg2 from your recorder or if it came from
the encoder on your machine and the same drive). Hope that
helps some.

mikey
Related resources
Anonymous
December 23, 2004 4:46:52 PM

Archived from groups: rec.video.desktop (More info?)

"Brian" <wrote ...
> My DVD Recorder has a firewire DV In/Out connection.
> If I transfer video from the DVD Recorders hard drive to the computers
> hard drive using the firewire connection is there any loss in video
> quality?

Loss through the Firewire connection: likely none.

Loss because of hard drive format in your DVD recorder
(MPEG2?): likely yes.

> The reason to transfer video is to do more editing on the computer
> such as adding fades etc.

You'd be better off transfering via Firewire to the computer hard
drive.
Anonymous
December 23, 2004 4:46:52 PM

Archived from groups: rec.video.desktop (More info?)

Brian wrote:
> My DVD Recorder has a firewire DV In/Out connection.
> If I transfer video from the DVD Recorders hard drive to the computers
> hard drive using the firewire connection is there any loss in video
> quality?
> The reason to transfer video is to do more editing on the computer
> such as adding fades etc.

The DV format is not the same as DVD format so a conversion
will take place. You won't lose too much since you'd be converting
to a higher bitrate format, but I`d guess the better way to do it
would be to burn to a DVD and edit that - there are programs that
can do that with zero loss (without recompressing).

DV = 11Gb/hour DVD = 1.5GB/hour
DV also compresses each frame independantly, where MPEG (DVD)
merges information from previous and future frames.

The DVD recorder is probably internally all MPEG2 (DVD) format,
with conversion to DV format done at the firewire port (both ways).

More quality is lost at the input stage - camcorder to DVD recorder, or
broadcast to hard drive - than anywhere else though
(11GB compressed down to 1.5 )

--
Mike
Anonymous
December 23, 2004 4:46:52 PM

Archived from groups: rec.video.desktop (More info?)

On Wed, 22 Dec 2004 19:46:51 -0500, Brian wrote
(in article <o65ks09rnnovp2eik00mhui8pf7dnv883q@4ax.com>):

> My DVD Recorder has a firewire DV In/Out connection.
> If I transfer video from the DVD Recorders hard drive to the computers
> hard drive using the firewire connection is there any loss in video
> quality?
> The reason to transfer video is to do more editing on the computer
> such as adding fades etc.
>
> Regards Brian
>

I have heard about export issues to DVD when the video is to played on NTSC
TV, but that's an mpeg thing.

Regards,

Ty Ford



-- Ty Ford's equipment reviews, audio samples, rates and other audiocentric
stuff are at www.tyford.com
Anonymous
December 23, 2004 4:46:53 PM

Archived from groups: rec.video.desktop (More info?)

In article <596ks09f2trrmpmjipu8u8o6tv10skitlj@4ax.com>,
kevingleeson@imagine-it.com.au (Kevin Gleeson) wrote:
> Haven't heard of a DVD with Firewire but as Firewire is simply a data
> transfer there will be no quality loss.
Many set-top DVD recorders have a firewire input.

> (How the hell it converts an mpeg stream to a DV stream is beyond me
> though).
It just converts the DV to MPEG internally. It's an easy way to dump your
camcorder footage to a DVD for backup.

Iain Laskey
Practical PC Online www.practicalpc.co.uk
Anonymous
December 23, 2004 4:46:53 PM

Archived from groups: rec.video.desktop (More info?)

Hi. I'd like to jump in here and see If I can get this straight. I'll be
buying a DV camcorder soon (still researching the best deal for my available
cash) and my biggest issue will be what results I will get when I transfer
my DV footage onto my computer via firewire, edit it, then shoot it back to
the camcorder. Will I get artifacting, dropped frames, etc?

This was the reason I stopped video editing before albiet because I used an
analog camcorder and capture card which didn't transfer cleanly and I had a
lot of dropped frames and artifacts.

I had heard the DV to computer was essentially lossless because its a
straight transfer of the video to the computer without any compression. Have
I heard wrong?

Thanks

"Mike Redrobe" <mike@redrobe.net> wrote in message
news:6Gxyd.5552$Ar5.532@text.news.blueyonder.co.uk...
> Brian wrote:
> > My DVD Recorder has a firewire DV In/Out connection.
> > If I transfer video from the DVD Recorders hard drive to the computers
> > hard drive using the firewire connection is there any loss in video
> > quality?
> > The reason to transfer video is to do more editing on the computer
> > such as adding fades etc.
>
> The DV format is not the same as DVD format so a conversion
> will take place. You won't lose too much since you'd be converting
> to a higher bitrate format, but I`d guess the better way to do it
> would be to burn to a DVD and edit that - there are programs that
> can do that with zero loss (without recompressing).
>
> DV = 11Gb/hour DVD = 1.5GB/hour
> DV also compresses each frame independantly, where MPEG (DVD)
> merges information from previous and future frames.
>
> The DVD recorder is probably internally all MPEG2 (DVD) format,
> with conversion to DV format done at the firewire port (both ways).
>
> More quality is lost at the input stage - camcorder to DVD recorder, or
> broadcast to hard drive - than anywhere else though
> (11GB compressed down to 1.5 )
>
> --
> Mike
>
>
Anonymous
December 23, 2004 4:46:54 PM

Archived from groups: rec.video.desktop (More info?)

"Iain Laskey" wrote ...
> Kevin Gleeson wrote:
>> Haven't heard of a DVD with Firewire but as Firewire is
>> simply a data transfer there will be no quality loss.

> Many set-top DVD recorders have a firewire input.

>> (How the hell it converts an mpeg stream to a DV stream
>> is beyond me though).

> It just converts the DV to MPEG internally. It's an easy way
> to dump your camcorder footage to a DVD for backup.

The key word being "backup" as MPEG may not be of sufficient
quality for subsequent production editing. (Unless you are just
excising commercials from South Park or the equivalent).

BTW, DV is actually ~13.5 GB/hour, not 11GB as reported
in another msg.
Anonymous
December 23, 2004 4:46:54 PM

Archived from groups: rec.video.desktop (More info?)

"atarileaf" wrote ...
> Hi. I'd like to jump in here and see If I can get this straight.
> I'll be buying a DV camcorder soon (still researching the
> best deal for my available cash) and my biggest issue will
> be what results I will get when I transfer my DV footage onto
> my computer via firewire, edit it, then shoot it back to the
> camcorder. Will I get artifacting, dropped frames, etc?

If you..
1) Retain DV encoding all the way through (i.e. don't compress
it further to MPEG, DIVX, Real, WMV, etc.)
2) Use a computer of sufficient horsepower (likely anything
that will run a current OS)
3) Use Firewire (not USB) interconnection
then you will likely completely avoid artifacting, dropped
frames, etc.

> This was the reason I stopped video editing before albiet
> because I used an analog camcorder and capture card which
> didn't transfer cleanly and I had a lot of dropped frames and
> artifacts.

Yes, that sounds like typical results from a less-than-optimal
video capture card. Note, however that there are video capture
cards/devices that many of us have found to be virtually trouble-
free (ie. Canopus ADVC-100, etc.)

> I had heard the DV to computer was essentially lossless
> because its a straight transfer of the video to the computer
> without any compression. Have I heard wrong?

You have heard correctly.
Anonymous
December 23, 2004 5:02:31 PM

Archived from groups: rec.video.desktop (More info?)

Thank you Richard. Your answers are very helpful and I appreciate it since
I'm sure a lot of these newbie questions come along often.

Cheers!


"Richard Crowley" <rcrowley7@xprt.net> wrote in message
news:10sm53no0n9evf4@corp.supernews.com...
> "atarileaf" wrote ...
> > Hi. I'd like to jump in here and see If I can get this straight.
> > I'll be buying a DV camcorder soon (still researching the
> > best deal for my available cash) and my biggest issue will
> > be what results I will get when I transfer my DV footage onto
> > my computer via firewire, edit it, then shoot it back to the
> > camcorder. Will I get artifacting, dropped frames, etc?
>
> If you..
> 1) Retain DV encoding all the way through (i.e. don't compress
> it further to MPEG, DIVX, Real, WMV, etc.)
> 2) Use a computer of sufficient horsepower (likely anything
> that will run a current OS)
> 3) Use Firewire (not USB) interconnection
> then you will likely completely avoid artifacting, dropped
> frames, etc.
>
> > This was the reason I stopped video editing before albiet
> > because I used an analog camcorder and capture card which
> > didn't transfer cleanly and I had a lot of dropped frames and
> > artifacts.
>
> Yes, that sounds like typical results from a less-than-optimal
> video capture card. Note, however that there are video capture
> cards/devices that many of us have found to be virtually trouble-
> free (ie. Canopus ADVC-100, etc.)
>
> > I had heard the DV to computer was essentially lossless
> > because its a straight transfer of the video to the computer
> > without any compression. Have I heard wrong?
>
> You have heard correctly.
Anonymous
December 24, 2004 1:42:51 PM

Archived from groups: rec.video.desktop (More info?)

Iain Laskey wrote:
> In article <596ks09f2trrmpmjipu8u8o6tv10skitlj@4ax.com>,
> kevingleeson@imagine-it.com.au (Kevin Gleeson) wrote:
>> Haven't heard of a DVD with Firewire but as Firewire is simply a data
>> transfer there will be no quality loss.
> Many set-top DVD recorders have a firewire input.

...but all DVD recorders immediately compress to MPEG
and so lose (some) quality.

If you want to transfer footage with no loss, use a PC with firewire.

--
Mike
Anonymous
December 27, 2004 4:06:38 AM

Archived from groups: rec.video.desktop (More info?)

On Thu, 23 Dec 2004 13:36:28 -0500, "atarileaf"
<hickorysticks@cogeco.ca> wrote:

>I had heard the DV to computer was essentially lossless because its a
>straight transfer of the video to the computer without any compression.

Right. Just an exact copy of digital data from tape to harddrive.
Anonymous
December 28, 2004 12:08:15 AM

Archived from groups: rec.video.desktop (More info?)

Okay, I'm confused then. Apologies in advance.

DV video *is* compressed, right? Data rate is around 2.8Mbps? Are we saying
that this is lossless compression, or lossy?

DV playback through the camcorder (via A/V connection to TV) is, of course,
beautiful. DV captured to PC, encoded to DVD format (via TMPGEnc 3.0 at
9200kbps!!), burned to DVD and then played back on the TV is less beautiful.
And I don't get it. I should have equal quality.

I'm missing something. What am I missing?
Anonymous
December 28, 2004 12:08:16 AM

Archived from groups: rec.video.desktop (More info?)

RedmondMan wrote:

> DV playback through the camcorder
> (via A/V connection to TV) is, of course,
> beautiful. DV captured to PC, encoded
> to DVD format (via TMPGEnc 3.0 at
> 9200kbps!!), burned to DVD and then
> played back on the TV is less beautiful.
> And I don't get it. I should have equal
> quality.
>
> I'm missing something. What am I missing?

The "encoded to DVD format ... burned to
DVD" involves MPEG rendering, doesn't it?
Anonymous
December 28, 2004 12:08:16 AM

Archived from groups: rec.video.desktop (More info?)

"RedmondMan" wrote ...
> Okay, I'm confused then. Apologies in advance.
> DV video *is* compressed, right?

Yes, DV is compressed 5:1

> Data rate is around 2.8Mbps?

My rule of thumb is 13.5 Gb/hour

> Are we saying that this is lossless compression, or lossy?

DV compression is lossy.

> DV playback through the camcorder (via A/V connection
> to TV) is, of course, beautiful.

You are viewing video that was compressed only once to
DV (5:1) and then decompressed and viewed.

> DV captured to PC, encoded to DVD format (via TMPGEnc
> 3.0 at 9200kbps!!), burned to DVD and then played back on
> the TV is less beautiful.

Video DVDs are compressed MUCH more than DV because of the
amount of space available on the disk and the design constraints of
DVD players.

> And I don't get it. I should have equal quality.
> I'm missing something. What am I missing?

I can put 2 hours of video on a DVD (in the DVD-standard MPEG2
encoding) But I can put only ~20 minutes of DV on a 4.7Gb DVD
disc. The difference is the amound of compression. Clearly DVDs
are compressed significantly more than DV video.
Anonymous
December 28, 2004 2:13:30 AM

Archived from groups: rec.video.desktop (More info?)

>The "encoded to DVD format ... burned to
>DVD" involves MPEG rendering, doesn't it?

Yes, but at a *higher* bitrate than the original DV-AVI! Therefore I should
not lose quality. That's what I'm getting hung up on.
Anonymous
December 28, 2004 2:13:31 AM

Archived from groups: rec.video.desktop (More info?)

RedmondMan wrote:
> Don Lathrop wrote:

> >The "encoded to DVD format ... burned to
>>DVD" involves MPEG rendering, doesn't it?

> Yes, but at a *higher* bitrate than the original
> DV-AVI! Therefore I should not lose quality.
> That's what I'm getting hung up on.

I think the rendering itself causes a degradation
of quality. The bitrate will not make up for that.

Think of playing a wonderful CD on a terrific
stereo system for your friend over a telephone
line. He may record it with a digital mastering
system capable of high-quality audio reproduction,
but the source is not going to be any better
than what comes over the telephone.

I think once you render to DVD, you're going
through that process that causes degradation.
You can minimize it, but it won't look like the
tape capture or the AVI file.

I might be wrong, but that's the way I see it.
That's why I always save original AVIs and
tape captures. I don't rely on DVDs to archive
my video, since it's been degraded.
Anonymous
December 28, 2004 3:05:07 AM

Archived from groups: rec.video.desktop (More info?)

>I can put 2 hours of video on a DVD (in the DVD-standard MPEG2
>encoding) But I can put only ~20 minutes of DV on a 4.7Gb DVD
>disc. The difference is the amound of compression. Clearly DVDs
>are compressed significantly more than DV video.

Bear with me. I've done the same math. Say I only want to fit 20 minutes of
DV on a DVD. I should be able to encode at a much higher bitrate. And in
fact, TMPGEnc lets me encode to a bit rate of 9200 kbps, much higher than the
2800 kbps that my DV-AVI was originally captured at. Now, obviously, I can't
*increase* the quality of the video by encoding at a higher bit rate (LOL), but
I should *not*, *not*, *not* suffer degradation.

I'm left to conclude that the loss is happening at capture time, rather than at
encoding time. Right? 5:1 lossy compression is still lossy, yes?
Anonymous
December 28, 2004 3:05:08 AM

Archived from groups: rec.video.desktop (More info?)

"RedmondMan" wrote ...
> >I can put 2 hours of video on a DVD (in the DVD-standard MPEG2
>>encoding) But I can put only ~20 minutes of DV on a 4.7Gb DVD
>>disc. The difference is the amound of compression. Clearly DVDs
>>are compressed significantly more than DV video.
>
> Bear with me. I've done the same math. Say I only want to fit 20
> minutes of DV on a DVD. I should be able to encode at a much higher
> bitrate.

No, you cannot. DVD players are limited in their ability to handle
bitrates. This is a hardware limitation on the reading end of the
chain and there is nothing you can do about it at the encoding/writing
end to get around these limits. You may be able to make high-bitrate
"DVD-like" disks that will play on computers, but not on standalone
DVD players.

That is why you can get 2 hours in MPEG2, but only 20 minutes in
DV on a 4.7GB disc. That is why DVDs look visibly inferior to
native DV video files.
Anonymous
December 28, 2004 3:25:49 AM

Archived from groups: rec.video.desktop (More info?)

>Bear with me. I've done the same math.

Woo hoo! I'm an idiot! Okay, I'm happy now.

I confused bits per second with bytes per second.

And I should really know better.

Which leaves me wondering one thing:

Why do DVD movies look so much better than home movies, given the same bitrate
constraints?
Anonymous
December 28, 2004 3:25:50 AM

Archived from groups: rec.video.desktop (More info?)

"RedmondMan" wrote ...
> Why do DVD movies look so much better than home movies,
> given the same bitrate constraints?

1) The original source material is "cleaner" (less noisy).
Video noise, even noise that you don't immediately notice
can steal valuable information space away from the desired
picture detail. Some (many?) encoding applications attempt
to reduce this noise before encoding, but there is no substitute
for high-resolution, well-lit, properly exposed video/film.

2) The people who encode Hollywood movies use much
higher-end software/encoders. I believe a copy of the software
that is commonly used for commercial DVDs costs $10,000 or
more per copy.

3) The people who encode Hollywood movies go through
them shot-by-shot and manually "budget" how much compression
(and therefore how much data space on the disk) is used. They
compress simple scenes (like fluffy clouds in the sky) more than
scenes that are complex and/or contain rapid movement where
you need lower compression to preserve the content.
Anonymous
December 28, 2004 4:02:30 AM

Archived from groups: rec.video.desktop (More info?)

Okay, I'm satisfied, although a little disappointed. I thought I'd be taking a
step up from my old analog Hi-8 dubbed to VHS home videos for the relatives (by
moving to DV video transferred to DVDs for the relatives).

Thanks for the replies.
Anonymous
December 28, 2004 4:13:21 AM

Archived from groups: rec.video.desktop (More info?)

"RedmondMan" <redmondman@aol.com> wrote in message
news:20041227200230.21699.00002267@mb-m12.aol.com...
> Okay, I'm satisfied, although a little disappointed. I thought I'd be
taking a
> step up from my old analog Hi-8 dubbed to VHS home videos for the
relatives (by
> moving to DV video transferred to DVDs for the relatives).

You should be a step up from VHS dubs. The DVD you create that is 9Mbps
MPEG-2 should look as good as the original DV. I'm not sure why you have a
problem. When you say it looks worse, what do you mean? Is it blurry? Do
you see lots of artifacts (blockiness) on motion? Do you see artifacts on
scenes with little motion? Does it get jerky on horizontal pans? Does the
original DV played from the camera look as good as your Hi-8?
Anonymous
December 28, 2004 4:29:58 AM

Archived from groups: rec.video.desktop (More info?)

>When you say it looks worse, what do you mean?

I'm glad you asked. My main complaint is blurriness & low contrast. There's a
small amount of artifacting on high motion, but I don't care that much --
there's not a lot of high motion. No artifacting on scenes with little motion.
Horizontal pans are okay.

>Does the
>original DV played from the camera look as good as your Hi-8?

Here you've caught me in an omission. The DV camera (Panasonic DV203) is a
step down from the Hi-8 camera (Sony TR500). So as Richard points out, there's
no substitute for the highest quality input source.

To flesh out the picture, I did an A/B/C/D comparison for the family yesterday
(from the same DV-AVI capture):

A - VideoCD (MPEG1).
B - SVCD (MPEG2).
C - DVD (MPEG2, obviously).
D - DV camera.

A was horrible. We immediately played frisbee with the CD. B was surprisingly
good, and is a nice alternative to DVD for shorter movies. D was the sharpest,
highest-contrast of them all. I want to improve the quality of C to get it
closer to D -- if possible.
Anonymous
December 28, 2004 7:44:58 PM

Archived from groups: rec.video.desktop (More info?)

RedmondMan wrote:
>>When you say it looks worse, what do you mean?
>
>
> I'm glad you asked. My main complaint is blurriness & low contrast. There's a
> small amount of artifacting on high motion, but I don't care that much --
> there's not a lot of high motion. No artifacting on scenes with little motion.
> Horizontal pans are okay.

I'm suprised that Tmpeg at 9Mbps looks so poor. Are you using 2 pass
encoding? Is it VBR, CBR, or CQ? Try using 2-pass CQ. Also try the
Cinema Craft Basic encoder. You can get the trial (3 minute limit) at
www.visiblelight.com. If it looks better the retail version is IIRC
about $60.

> To flesh out the picture, I did an A/B/C/D comparison for the family yesterday
> (from the same DV-AVI capture):
>
> A - VideoCD (MPEG1).
> B - SVCD (MPEG2).
> C - DVD (MPEG2, obviously).
> D - DV camera.
>
> A was horrible. We immediately played frisbee with the CD. B was surprisingly
> good, and is a nice alternative to DVD for shorter movies. D was the sharpest,
> highest-contrast of them all. I want to improve the quality of C to get it
> closer to D -- if possible.

You should be able to get it very close.
!