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alexxi
03-12-2004, 12:50 PM
When I encode a file to a Mpeg2 Stream (CBR9500), I have a lot of artefacts in my stream.
Captured from DVCPRO/Beta/or Cameras to a RTV, regardless which Input[Comp/YC/YUV] and encoded with Tmpeg, has the same result as rendered to an uncompressed avi and encoded with premiereproīs MainConcept or Canopus ProCoder.
The same footage captured and encoded with my Digisuite or RTX100 is very clean.

What happens?

thx
alexx

edmellnik
03-12-2004, 03:28 PM
what are you using for play back of the mpeg 2 files.

I had a similiar problem but there was nothing wrong with the
file. it was the Mpeg windows player vision I was using.

ed

alexxi
03-14-2004, 12:00 PM
You are actually right , if I play the Stream on another PC, quality is much
better , but not correctly clean.
It is interesting, if I show an MPEG stream , rendered by an other System which looks good and clean,
on the VT3, there are likewise strong artifacts in the picture (regardless which player: MediaPlayer or VT vision) .
Thereby I found out the fact, that I cannot use any material with a DV-Codec: Playing DV-Files [rendered on different systems] with VT3 are full of particles. Finally when I record any material with VT3īs Built-In DV-Codec itīs a really worse quality...


So what is to do with VT3`s mpeg2 player?
Anyone using DV with VT3? I know it is an uncompressed system, I have no intentions to record on DV,
but I have tons of MPEG2 -and DV-Material on several Harddiskplayers, and it will be great, if VT3 could use them directly [via local network], without another capturing. [this files play on every other system,]

alexx

djlithium
03-29-2004, 10:33 AM
The quality of the output of your MPEG 2 video on your VT3 is completely dependent on the decompressor that you have loaded and accessable to direct show.
The Vt3 software calls for this codec and provides it with the decompression functions.

There are several reasons for this.

1. NewTek was superfsking smart when it came to implimenting playback for various formats by using WM player directshow codecs. They avoid a lot of the license BS from the MPEG group by doing this and that would jack the price of the software out of the box by several dollars. By calling for the decompression capabilities of a directshow mpeg2 filter from window and windows media player libs, the whole licence issue is bypassed.
2. The output is completely dependent on the quality of the decompressor and not all codecs are made equal. There are several "free" and thus crappy codecs out there that will get most home user types by on what they need to do like play DVDs or rather rip DVDs and for us VT3 people that's just not good enough.

Solution: Search out a good MPEG2 codec that you can buy that supports direct show for Windows Media Player (most do).

Problem solved.

This is why you are getting different output quality on different machines. The codec that you have right now is probably not the best.

alexxi
03-29-2004, 01:31 PM
thx for the answer

Yes, I understand this concept, but on my VT3 must be another crap.

As I know mainconcept[en]decoders are working great on all other machines, Ligos also and they are wether cheap nor crappy.
The only codec which works well (on monitor, Iīm not shure that itīs really okay) on my machine is rtv and uncompressed avi nothing else! I downloaded newest versions of mainconcepts dv-codec and mjpeg... no way! artefacted picture.

When Iwant to make a mpeg2 from my rtv or uncompressed file with Tmpeg or procoder or premiere pro, mpeg2 stream has the same artefakts as dv....
But there are more other disappointments, this is only one part which annoys me and steals my time.

Anyhow, Iīm to old for such games, my dealer will come next week for a solution which newtek promises in their announcments, otherwise they can take the box and do what ever they want, but without me...

alexx

djlithium
03-29-2004, 04:22 PM
It's not a Toaster problem dude.

There are settings in these codecs for output quality levels.
Do some reading :)

The VT3 is the bomb man. Nothing on earth does what I need done except the system I have based around it for what I do and I can't imagine anything else being put together the way this is and actually work on any other platform and still be portable like we have it here.

Go see... www.imagecorp.net

alexxi
03-30-2004, 02:40 AM
Originally posted by djlithium
It's not a Toaster problem dude.
maybe you are right, but itīs a newtek or newteks dealer problem.
I bought this System as a mobile TV-Studio in a box, as a TurnKey System, as a system which delivers what announced on Newteks homepage. What I got is a handicraft-system....

There are settings in these codecs for output quality levels.
Iīm working with digital video for over 10 years in all kind of variations, Avid , Media 100, Videomachine, Digisuite and so on...I know about settings and codecs very well....

Do some reading :)
There must be a very exclusive and special adjustment in toaster enviroment for thousand times tested dv codecs....and if it is, it must be a big secret, where is the documentation:"Special handling with DV or MPEG2 in VT3"

The VT3 is the bomb man. Nothing on earth does what I need done except the system I have based around it for what I do and I can't imagine anything else being put together the way this is and actually work on any other platform and still be portable like we have it here.

Yes sounds really good and this was exactly the reason, why I want to have such a box !

Why does Newtek not give clear rules for building a stable and working system to the distributors. There must be a configuration out there, which handles Liveswitching/Uncompressed/ DV and Encoding together without problems, this is all what I want! Where is the paper! ("recommendations" is NOT the solution!)

I donīt want to bore you with details, but beginning from Liveswitching (not acceptable latency and glitches /on preview switching like a 30year old b/w tube TV), Crashes, DV and Mpeg2 issue, start and shutdown problems and so on, itīs not a system which you like to work with......

alexx

BTW:
VT3/SX8/RS8/Genlock /DualXEON 3,06 /SUPERX5DAE /2GB Reg ECC RAM /160GB ATA SYSTEM /8x 72GB U-320 SCSI /ATTO U320 DualChannelController /PNY Quadro FX500 128MB /1 Firewire /19"rackmounted /Wacom GraphireStudioXL