Save DV AVI problem

[Guest]

Been trying to "Save to Tape" using Sony SCD23 camera via firewire to HP
Pavillion notebook (80GB external HD). Using 10 sec .avi clip I get about 50
sec of jerky, stop and go, slo mo video on tape. Also tried "Save to
Computer" in DV AVI format with same 10 sec (1.3MB) .avi clip, get 40MB DV
AVI file that has same jerky performance when played with Real One or Windows
Media players. The source .avi plays fine as does .wmv file created from same
clip.

Help?

Thanks.

 

[Graham Hughes]

Try
defragging hdd.
save to another hdd than the one the O/S is on.
Turn off all apps not required include internet/a-virus/firewall/screensaver
etc.
Check out windv, just for capture and export, often works well wehn MM
doesn't. see here for a link to download
http://www.simplydv.co.uk/simplyBB/viewtopic.php?t=1165

Graham

 

[Guest]

Thanks Graham, tried those things to no avail. Tried windv, no difference.
For kicks also tried rename codec from Kelly, no change. Some additional
questions arise:

- I am using external 80GB HD (75GB free, 7200rpm) as source and destination
for all video files, projects etc. Does it matter that MM2 app is running out
of local HD (20GB, 10GB free, defragged).

- External HD is connected to PC via USB. HD is USB 2.0 capable, PC is not
(1.0?). Do I need higher BW connection between PC and external HD (USB 2.0 or
firewire) to reap the benefit of all this storage space I just bought?

- Regarding turning off all other apps, I've seen references to turning off
all unnecessary processes. How is this done? I shutdown virus SW, firewall
etc and task manger shows no apps running. But under Proceess tab it lists 50
or so processes. How do I know what ones to disable?

- I've seen references to AVI-1 vs AVI-2 formats. Is there anything here to
consider?

Thanks
JS

 

[Graham Hughes]

I would say most definately it is the usb1. USB2 is fast enough in theory to
pass dv signal, but it can only work at those speeds for short bursts of
information and cannot sustain it, so even this is not going to help when
sending live information. You really need firewire to be able to do it. This
can be connected up in series, ie you connect the pc to the ext drive by
firewire, and then the cam to the ext drive by firewire. You get device
control still and all should work great.
As for the other pieces.
It is best to store video files etc on another hdd, so this is good.
May not need it when you have firewire drive, but do a google search for
"enditall" which will turn off all uneeded apps for you.
Different apps will make different file types some type 1 some type 2. The
only problem this may cause is importing the avi file into another app which
doesn't accept that file type. So forget this until you have another problem

 

[Guest]

Thanks again, sounds like good advice but before I spend any more money for
HW a few more questions to help me understand whats goin on:

- When I save 10 sec .avi clip as movie to computer in DV AVI format does
any of the HD/USB/Firewire stuff matter? I understand for real time process
like save to camera or playback in WM9 but saving to computer is just
crunching and saving data, it will take as long as it takes but quality of
the resulting file should not be effected by BW to hard drive. Is this
correct?

- If above is correct is there anyway to verify the rendered movie file
before laying out bucks for firewire HD (suspect not but would be nice to
verify the SW before blaming the HW).

- Why does the resulting DV AVI movie file grow to 45MB from 1.7MB source
..avi clip? I’m doing nothing more than dropping .avi clip in MM2 timeline (no
added effects, transitions etc) and then saving as movie in DV AVI format.
When I save as wmv (“best for computerâ€) resulting movie file is only 0.6 MB
and plays ok. What is all the extra data in the DV AVI file? What is
difference between source file format (.avi) and format needed to send to
camera (DV AVI)?

Thanks for helping me wade through this.

 

[Graham Hughes]

See below.

--
Graham Hughes
MVP Digital Media
www.dvds2treasure.com
www.simplydv.com

Thanks again, sounds like good advice but before I spend any more money for
HW a few more questions to help me understand whats goin on:

- When I save 10 sec .avi clip as movie to computer in DV AVI format does
any of the HD/USB/Firewire stuff matter? I understand for real time process
like save to camera or playback in WM9 but saving to computer is just
crunching and saving data, it will take as long as it takes but quality of
the resulting file should not be effected by BW to hard drive. Is this
correct?

This is correct. If you save an AVI to the hdd then it should be fine if all
the components are up to the task and nothing is interfering as we have run
through before.

- If above is correct is there anyway to verify the rendered movie file
before laying out bucks for firewire HD (suspect not but would be nice to
verify the SW before blaming the HW).

To check the file is fine you can just play it in WMP.

- Why does the resulting DV AVI movie file grow to 45MB from 1.7MB source
.avi clip? I'm doing nothing more than dropping .avi clip in MM2 timeline (no
added effects, transitions etc) and then saving as movie in DV AVI format.
When I save as wmv ("best for computer") resulting movie file is only 0.6 MB
and plays ok. What is all the extra data in the DV AVI file? What is
difference between source file format (.avi) and format needed to send to
camera (DV AVI)?

I'm not sure why you are getting such a huge difference in file size. I
can't say I have ever noticed it, so just ran a test using MM. File imported
was, 143,561kb. File sized saved from MM, 144,539kb. Are you sure it is a
std DV-AVI you are using as your source file?

 

[Guest]

Hi Graham,

Regrading verifying DV-AVI file in WMP, that is where I see the problem. Slo
mo, broken up video. Same thing if I save to tape.

On subject of file size, maybe this is where disconnect is. Bear with me.
Maybe we can do this experiment on same file:

In my computer Program Folder, there is Movie Maker folder that contains a
sample video file. Guess it is installed with MM2, maybe you have same. It is
360KB, 12 sec clip of kid on playground.

In MM2 I select Import Video, and browse for this file.
MM2 puts it into Collection Pane, it shows up as 5 clips, each about 2 sec.

Drop the 5 clips sequentially into timeline. Plays fine in MM2.
Select “Save to my computerâ€
Next screen is name and destination of movie file to be created.
After that comes Movie Setting screen
Select “Other Settings†then from pull down menu “DV-AVI (NTSC)â€
At bottom of screen there is a “Movie File Size†indicator.
It says “Estimated space required: 48 MBâ€
So I already know it is growing substantially from 360KB, but proceed to
save anyway.
Resulting file – 43.3 MB, and lousy playback.
File size and results are same if I save to local HD or external.



???

 

[Graham Hughes]

That file is a wmv, which is why it grows. Have you tried with an avi from
your camcorder?

 

[Guest]

If I capture from camera with MM2 it creates wmv file which seems ok. As far
as I can tell there is no way to capture in DV-AVI in MM2. Of course if I use
captured wmv in timeline and save back to tape or to computer in DV-AVI I get
lousy performance as described.

If I use windv to capture from camera in DV-AVI format resulting captured
video file has same lousy performance.

At this point it seems that I'm just not set up to handle DV-AVI format,
which is what I need to achieve goal of saving movies to tape so they can be
viewed onTV. Guess I'll bite the bullet, scrounge for loose change behind the
couch and get firewire HD. We'll see what happens.

 

[Rehan]

If I capture from camera with MM2 it creates wmv file which seems ok. As

far
as I can tell there is no way to capture in DV-AVI in MM2.

Your problem is that you are not using firewire connection to the camcorder
to capture. MM2 does not allow saving in DV AVI format if it determines the
data throughput requred wont be able to achieve via USB.

Firewire card and cable is dirt cheap these days. I would recommend you dont
waste any more of your time and resources and get the firewire asap. It will
allow you to capture in DV format (highest possible quality).

As Graham said USB is not up to the job when it comes to sustained data
throughput such as movie capture. Note it is not movie "copy" from your
camera to disk. The capture process is more involved: in simple terms the
camcorder plays the movie in real time and the capture program on the
computer side takes snapshots and encodes. So you see that if the data is
not coming fast enough, the capture process would miss many frames.

DV format uses very small and simple compression schemes in order to
maintain the quality. On the other hand a WMV format is geared towards
saving diskspace while maintaining quality so it can employ a lot of
complicated compression algorithms to do that. This requires a lot of
processing and only a PC can play these formats. There are plans for making
standalone dvd players which would be able to play WMV format but non exists
at the moment.

As per external HD, you should avoid it for the initial capture or output
from MM. Once the DV AVI is captured on the main HD, you can copy it to
external HD to make some space. The reason is again the data throughput
required to capture might not be available with external HD.

 

[Guest]

Rehan,
I am using firewire to capture from camcorder. The USB connection is to
external HD, question is should I firewire that external HD interface. Per
your response sounds like internal HD should work, at least for small 10sec
clips I am experimenting with.
To summarize:
Camcorder -- firewire -- PC-- internal HD - DV-AVI format - get dropped
frames etc. on captured video played back with WM9.
Camcorder -- firewire -- PC -- external USB HD - DV-AVI format - get dropped
frames etc on captured video played back with WM9

Same problem for both cases if I go the other way, saving movie to camcorder
using .avi sample clip.
Same problem for both cases if I save .avi clip to computer in DV-AVI, play
in WM9.

No change if I shut down all apps, use enditall, renamecodecs, etc.

For all above with wmv format get decent results, except of course can't
save that format to camcorder.

Regarding PC firewire connection, it is built in to PC. Any chance it is not
up to snuff? Are all firewire HWs created the same?