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jeremy092288
11-05-2003, 08:04 AM
Hello to all,

I am going to fill all of you in on what I am doing with my toaster so you can all help me a little better.

I basically produce 1 to 2 videos a week from actually shooting it to burning it on DVD.

These videos can range from 20 minutes to one I just did that was an 97 minutes.

My problem is I sometimes do not have near enough harddrive space to capture and hour and 1 minute of footage and then cut off 30 seconds on the end (and beginning) and render it out.
(I have two SCSI 73s)

Questions

1. Is there a more profficient way to do things?

I have always done Uncompressed AVI

2. But if they are going to DVD isn't the DVD going to convert it to MPEG 2? (I am using Ulead DVD Software)

3. Can I save the software a step and myself some harddrive space by rendering to MPEG 2?

4. Does my toster already have MPEG 2 codecs?

5. How many licks does it take to get to the center of a tootsie pop? :D

Thanks again you guys are awesome
Such smart people helping out a newbie like me

mgrusin
11-05-2003, 01:07 PM
I don't know of any real-time MPEG codecs for the Toaster, and I don't think we'll see any until computers get quite a bit faster. Notice that it takes several times realtime to encode your RTV files to MPEG. The Toaster is designed to do everything in realtime, so we're not there yet (but I'm sure we'll see it someday, probably in 2 or 3 years when we're all running 10GHz processors).

But don't despair. The brilliance of the Toaster is that it is so flexible. If you have a shorter production where you need maximum quality, definitely work in uncompressed format (which "costs" about 80GB/hour). But if you have a longer production, and can settle for -slightly- lower quality, you can capture in a compressed format, such as DV, which is compressed 5:1 and therefore only "costs" 13GB/hour. The nifty part is that the Toaster handles this transparently; everything works the same, it just takes less disk space.

I use DV type 2 all the time for productions up to 6 hours long (!), and it works great. There is a slight quality hit vs. RTV, but unless your original source is extremely high quality, you probably won't notice it. If you're using T3, the realtime DV codecs are already provided. If you're using T2, I suggest upgrading to T3 ($585), or purchasing the Mainactor DV Codec ($50 from www.mainconcept.de), which is the same codec used in T3. (Don't bother with the Microsoft DV codec available in the stock T2; it's not great). I haven't used it, but people have also recommended the Picvideo MJPEG encoder ($19?), which is another compressed format, and allows variable compression rates for even more flexibility (search this board for info).

Try doing your next show in DV (you can both capture and render to DV format; Ulead should be able to read DV natively), and see how it goes. I bet you'll like the results.

And at the risk of showing my age, the answer to question #5 is three (*crunch*). :p

Good luck! -MG

Jim_C
11-05-2003, 01:21 PM
After you complete your project with whatever flavor codec of choice, you can impzort the VT-Edit file directly into TMPGEnc. You dn't have to render it out as one big file again.
Or if using a different app you can save the projeect as an .avi file (note not render to avi but save as .avi from the save drop down)
then import that wrapped avi into another program.

I had to do this earlier today.
I had a one hour project. i didnt have time to do TMPGEnc then load into Encore DVD then Nero then burn, so I wrapped the project as .avi imported that into Encore then let Encore do the conversion to mpeg2. Quicker than TMPGEnc and nearly as if not as good as encoding.

good luck and ask away...
jim

eon5
11-17-2003, 12:38 PM
How can i record directly in mpeg2 file using VT3 ?

Where i can find the mpeg2 codec?

Jim_C
11-17-2003, 12:42 PM
>>How can i record directly in mpeg2 file using VT3 ?


You can't.

eon5
11-17-2003, 04:24 PM
OUCH!


;)

Jim_C
11-17-2003, 04:54 PM
>>OUCH!


I Know....

eon5
11-18-2003, 08:50 AM
MPEG-2 Video Codec (with Source Code)


http://www.mpeg.org/MPEG/MSSG/#source

>>> ???

vanguard
11-18-2003, 01:56 PM
We have a hardware based capture system in a seperate computer to cap the output of the VT directly to MPEG2.

We used to keep the authoring software on the same computer, but now we have it seperate with the server keeping the files in a group drive.

This way we can capture and author at the same time.

There are lots of HW based capture cards out there.

It costs more than share-ware, but there's no rendering ;)

Rich Deustachio
11-18-2003, 04:25 PM
Jerry, which one are you using and how is the quality?

RBernards
11-18-2003, 09:43 PM
Mpeg2 is a HIGHLY compressed format and is not designed for editing.

DVD-compliant mpeg2 is NOT and CANNOT be frame accurate
for editing. You can only edit on I-frames which are usually
about 1/2 second apart depending on settings.

Unless you are using a high end multipass hardware encoder,
software encoding will ALWAYS give you better results.
A multipass encoder, at best, is 2X real time. The first pass
analyzes the video and the second pass encodes.

I've been producing DVDs since 1996. Believe me, it was not fun
back then. Buggy software, high cost of media, encoders, etc.

Real time encoders are available however and can produce
good results but you will run into issues with challenging video.

I used to use an Canopus Amber real time mpeg2 encoder card
and was happy with it but did have to resort to software encoding
at times.
Then I used a Sonic SD1000 card and it too choked on some scenes in certain videos. Had to use TMPGenc.

Now I am no longer working at the same place and am back to using TMPGEnc for all my encoding.

It really seems that many people have misconceptions about
mpeg2.
It was designed for distribution, not acquisition or editing.

Sorry, there are no shortcuts at this time to high quality real time mpeg2 encoding that will work in all situations.
But I am picky about my quality. YMMV.

And dat's da fact, Jack.

sywitt
11-19-2003, 07:46 AM
To answer 2 of the original questions:

1. To save disk space, why not capture in the MainConcept DV format that's included with VT3? Another good space saver is PicVideo, but there's a minor charge to use it. You'll get a ton of space saving. We use them for long form stuff (plays, weddings). I visually can't tell the difference between the first generation compressed footage and uncompressed .

2. After doing that, run the footage thru TMPGEnc by saving the footage as a Toaster edit project and importing the project into TMPGEnc. If you do 2 pass VBR, you'll get the finest looking Mpeg2 footage you've ever seen.


Sy Witt
Ramona Rose Studio, Inc.

Rich Deustachio
11-19-2003, 02:42 PM
Yes TMPGEnc does have great quality but a two hour video takes 4 to 6 hours to encode.

Harri Raisa
11-19-2003, 03:11 PM
>>>Yes TMPGEnc does have great quality but a two hour video takes 4 to 6 hours to encode.

Hey! Do you work 24h/day ;) My machine don't need to rest, but I do :)

Harri

RBernards
11-19-2003, 03:40 PM
TMPGEnc encodes can be long but I've never been dissappointed
with its results.

In fact, I just finished 4 different DVDs where all the programs were between 2 1/2 to 3 hours long.
The client wanted each program to fit on one DVD.
I used TMPGEnc with bitrates as low as 3.1 Mbits
and it still looked great. I tweak a few things.

I set the motion search precision to *motion estimate (fast)*.
This dramatically decreases the encode times.
The 2 1/2 hour programs took about 3 1/2 hours to encode
and I had a hard time telling the difference between different encodes and the client certainly couldn't.

It was not challenging footage though. Very little motion.
Just a fancy intro, a talking head and a few graphics
and keys.

Client is happy.