Concatenated 2GB avi's

[miklos]

System: Matrox G400TV Marvel Windows '98
Matrox Technical advised
1. An AVI file over 2Gb is invalid and will not playback.
2. There is no point in creating an AVI file that is greater than 2Gb.

I'm aware of the 2GB rule under Windows '98 but I edit with
Avid Cinema which allows multiples of 2GB avi's to be
concatenated on the time line? I made and saved out 3.5GB avi file. However when I tried to reload into Avid or WMP I got an error "could not open as end of file was reached prematurely"

What does this mean technically and could I output/convert this 3.5GB movie to some readable format(other than VideoTape)eg MPEG?

Thanks
Miklos

[iant]

First off, try using VirtualDub. It's normally quite happy with oversize files up to 4 gig.
Also, don't use the Matrox capture. Use either VirtualDub or AVI_IO ( I use the latter. Less frame drops. ) Both of these can do multi-file captures with no frame loss inbetween which the Matrox app can't. ( I know...I've got one of these cards. )
Good Luck,
Ian

[miklos]

iant:
Thanks for your input. I've got VirtualDub but which codec do you use for capture? (I need
704x576@25fps from analog broadcast TV or SVHS tape)
However I would like to continue to edit with Avid as its supplied and not bad. I can still see no
value in creating a movie over 2GB in Avid unless I just want to output it to tape becaue you can't seem to do anything (so I believe) with a an avi file output greater than 2GB!
(Even VirtualDub {which as you say can capture up to 4GB} can't read it in)

So we get back to the question (and I'm sure this apples to other editors that concaternate on the time line) what can be done with the resultant movie. To get a 1/2 hr full screen edited movie your looking at a file over 4GB size.

Regards

Miklos

[iant]

Miklos,
Do your captures as multi segment captures using either VirtualDub or AVI_IO then frameserve the virtual single file created to your encoder. ( Check the How Tos on the left. )
As regards codecs, sorry but that's try a few and see how you go. My capture card has inbuilt MJPEG capture so I don't have a problem as it does most of the work. The most commonly recommended codecs here have tended to be HUFFYUV or an MJPEG codec such as PicVideo. It all depends on how much disk space you have, what your CPU can handle and how fast your system can write to the hard disks.
Hope this helps,
Ian

[iant]

Sheesh..I forgot the first part of your original post. Having a dumb day.
Don't try other codecs. Matrox MJPEG is just fine. Just do as I put in the first part of my earlier response. By doing a multi segment capture you produce a virtual single AVI of whatever length you need.

[miklos]

Ian,
Your suggestions sound pretty good and I'll certainly give this a try. I didn't realise "frame server" could output a multi segmented file direct to a transcoder. Yes we are both using MJPEG hardware codecs and I can get Full screen capture @6:1 3mb/s no problem. I don't think any other codecs can take advantage of G400 hardware compression so I guess they are not so efficient. It still a shame that it seems impossible to use a real timeline editor( which concatenates multi segments) and make use of all its features eg special effects, dissolves. sound additions. in this situation. VirtualDub good as it is, is not really an editor but I guess its a good compromise.

Miklos

[miklos]

Ian,
Just thought of this after I posted. What if I use my timeline editor to create a movie and save it out to my S-VHS VCR. Then import/capture it back multi- segmented to VirtualDub and then as you suggest frameserve the virtual file to a transcoder (SVCD).

Maybe some loss of quality though. What do you think?

Miklos

[iant]

Miklos,
Hate to tell you but VirtualDub can append multiple segments. The recommendation with this is not to use the Matrox capture as the actual frames per second varies on this from one clip to another. If you do your captures using either VirtualDub or AVI_IO you'll get a steady framerate so separate clips can easily be added together.

As for the idea of record out to vcr then back in again.....Don't do it! Definite quality losses there!

[miklos]

Cheers Ian,
I had a quick play with Frameserver after running <AuxSetup> but on launching it nothing much happened. I then read "Howto's" at VCDHelp and noted folders <aviproxy><dtv><plugins> were all missing in my setup of frameserver along with files <proxyoff/on.reg><readme.txt>!
I've no idea why they are'nt there as frameserver installed its.dll's OK and all speed tests passed OK?

Checking out the 4GB capture in VD (multi-segment ticked);got to 4079MB full screen with just 8 frames dropped; then all came to a halt <VD error> and program hung. ie. did not move on to next segment! Then I limited the capture to 1.9GB segments but same thing..halted.

The 4GB file loaded back in to VD only after error<Reconstructing missing index block>.

Looks like I've still some way to go. Thing I'll give AVI_IO a try and hope its somewhat easier to use.

Miklos

[iant]

Miklos,
Definitely use AVI_IO for capture.
The frameserver in VirtualDub isn't for capturing. It's for 'serving' the captured AVI to your encoder.

The halting will be because you probably didn't either allocate or activate a 'spill drive' As a result, it didn't know that you wanted more files captured.

The bits that are missing in VirtualDub can be obtained by getting an older release from the VirtualDub download page. Anything before 1.4.5 will have the proxy setting files and other bits included. Just copy these extras over into the same places in the new ones folder.

Hope this helps,
Ian