black blotches in my DVD

[ansberry]

I would search the archives, but I don't know what to call it. I imagine it is a common thing in digital video. The DVD that I burned has occassional blotches that flash on the screen. They look like large black pixels. It wasn't in the video before I compressed it and burned it. What is it called? What causes it? How can i avoid having it happen again?

thanks
Mike

[terryj]

one or two things:

I've seen this happen with some DIVX videos that
got processed from QT to movie that
I burned in Toast that came out like that on the DVD.
I had to go back, re-process through DIVX Doctor II,
then to QT, then run through Toast and it came out fine.
Apparently while encoding in Toast from the original DIVX
file it had problems processing, even with the all the
DIVX plug-ins installed within QT Pro.

The other thing was when I use to use CompUSA
cheap Media in the early days, i'd get the black blocks
AND the occasional stops and stutters in playing the disc.

Switching to better media helped the problem. Since
using TDK exclusively, the majority of problems
have been all related to the files themselves.

[ansberry]

These videos were captured through iMovie 4. Then I "shared" them to dv format and burned them with Toast 6.0.7. They showed no such blotches when run in iMovie before I compressed them. The blotches look a lot like what happens on my TV sometimes when the satelite is messing up. Can someone tell me what this glitch is called?

[maetel99]

I would guess you are seeing MPEG pixelation. This can happen when there is a frame motion prediction problem. It's probably a bug in Toast's MPEG encoder. Contact Roxio support tell them about it so they can fix it.

[terryj]

Yup, maetel99 got it.
Here is a url that points out some things:
http://boards.support.roxio.com/roxio/board/message?board.id=0000020&message.id=5368#M5368

Apparently the consensus is, don't let Toast do your
compression if you are exporting from FCP/FCE ( and to
that extent iMovie). Better to let Compressor or BitVice
do you compression, and use toast just to burn.

sucks, but at least they know it sucks.

[ansberry]

Where can I get "Compressor"? I checked out BitVice, but since I'm just getting started on this video stuff, I'm not ready to drop $125 on a download. Plus my dial-up connection (no fast internet in my neighborhood) would probably screw it up. I have ffmpegX. It will compress video into mpegs, won't it?

If I compress the files with a program other than Toast, will Toast still try to recompress them? When I loaded the files into the Toast window, it automatically compressed them into temp files.

Is there a burning program better than Toast?

thanks- Mike

[terryj]

Toast is great for burning files.
But what it lacks is a great COMPRESSION software module,
which is your main concern. It has a compression
module, but it works only based if the files
are within Quicktime Specs.
If the video or audio (or both) are out of spec,
then it's gonna be a bit of a problem.

You could instead try encoding the files with ffmpegx
and see then how the files play in Quicktime Pro.
If they play great in Quicktime Pro ( no blockiness,
no black spots) then they should pass Toast.
If they play like crap in QT, they won't pass Toast.
it's just that simple. Toast will try to re-encode them into
QT Spec, but if it doesn't pass QT in the first place,
then the encoding will fail.

Bitvice ( at $125) is a BARGAIN compared to Compressor,
which comes bundled only with either FCP or DVDSP
( $350 to $995), but the programs they are attached to
more than make-up for it.

[ansberry]

If I encode my movie with ffmpegX, then have toast convert it to a quicktime standard, won't I loose a lot of quality from the double compression? What is my best bet for choice of compression with ffmpegX, mpeg4?

thanks
Mike

[terryj]

Your best bet is to get it into .mov format in ffmpegx.
Mpeg-4[.avi] should be compliant though....
From there, it will re-encode in toast to MPEG.
Some of the MPEG standards in ffmpegx will
not allow you to bypass re-encoding in Toast.

Major would no more...I tend to only use ffmpegx
to get non compliant files to either QT compliant
mov or compliant avi's (mpeg-4), then re-edit in QT
and then save from there as QT mov files, to
be compliant with Toast.

[ansberry]

So if I save it as a .mov or a .avi file, Toast will not recompress it? Cool.

Thanks for the help. Slowly but surely I'm getting it together with this video stuff.

Mike

[terryj]

no, Toast will recompress it, but you will have it
in a COMPATIBLE spec where Toast won't freak out
trying to encode it. Toast MUST re-encode the video
to MPEG ( either -1 or -2) to get it to work as a VCD
or a DVD.

But what you want to be concerned of is if it passes
QT first. If it does that, than you chances are greater
of the file NOT getting hosed in the final encode.

Remember this motto:
Q.R.E.A.M.
( Quicktime Rules Everything (on) A Mac)

1.Encode your files to either .mov or .avi through ffmpegx.
2. if they play GREAT in Quicktime, send them to Toast to encode.
3. if not, then they will look worse in Toast.