why am i getting sudden blackouts on middle of rendering mpeg 1 for vcd?

Umran wrote on 11/13/2003, 1:31 PM
Could someone tell me why am i getting sudden blackouts on middle of rendering mpeg 1 for vcd standard, every time i render a pro job these blackout come constantly and then my projects start missing frames as if its running slow motion video... detail is below
i take a vcd standard file riped from dvd using intervideo dvdcopy and ripped it to vcd standard.. okay !... now when i open the file on vegas after reading audio file.. now i place a small effect like a logo on my video and now render it to 75min vcd standards .. in the begening it renders fine.. but after sometime its starts sudden black out in a middle of my rending and my projects starts working as if i rendered a slowmotion file... WHY!!! its effecting my time and money.... also note that i have chosen the whole project to it requirments as if im rending a NTSC vcd job.. the whole project is on NTSC VCD templete and also the file is im rendering is NTSC VCD standard.. and as in final im rendering NTSC VCD Templete to render the final job.. still it does that... WHY!!! someone please help me here.. i need help!!

Comments

Jsnkc wrote on 11/13/2003, 1:46 PM
VCD...Pro?? Anyways, first of all there is no need to "rip" a file off of a VCD, simply copy the file over that contains the video (I can't remember what the file extension is, just look for the biggest file on the disc) Anyways copy that file to your hard drive, then just change the extension to .mpg. That could be part of your problem. The second is when you take a already compressed format like MPEG-1 and rip it, edit it and then recompress it to a MPEG again you are just asking for problems. Your best bet would be to obtain the MPEG file in the method I described above, bring that raw file into Vegas, render thay out as a AVI DV or Uncompressed AVI file. Then, re-import the AVI file you created back into Vegas and use that to edit with. Either one or a combination of the suggestions should fix your problems.
BillyBoy wrote on 11/13/2003, 1:56 PM
You mean one or more blank (black) frames?

Using a MPEG as a source is generally considered a no-no. Some appllications handle this better than others. This is one thing Vegas isn't that good at. That said, I've done it many times. You need to be very careful there are no "blanks" to begin with by zooming way in on timeline and playing your finished project all the way through on an external monitor with your eyes riveted to the screen looking for any blanks then carefully weeding them out if any show up. Even then due to the rendering process a few can sneak in anyhow.

The problem is you're attempted to recompress a file that was always compressed and a low bitrate one at that. Also if you're editing be careful to avoid blanks that are gaps between events which can produce the same effect. A tiny gap in the timeline meaning its empty at some point will result in a blank (black) frame flashing by.

If during rendering the process starts to slow to a crawl and you're watching the preview and it starts to hang or breakup like get badly pixelated, maybe show larger green blocks, things like that, that is almost always due to trying to recompress and already compressed file. You source file could also be corrupted in one or more areas if it renders fine to start that hitting the bad part the encoder just can't handle it.
kameronj wrote on 11/13/2003, 3:19 PM
I agree with all of the above. But more so with trying to rerender a file that has already been compressed (i.e. MPEG).

In the case you described it does sound like you are recompressing an already compressed file - and thus your blackouts will pop in every now and then (especially if the rip you are working with is divx...but that is a different thread).

Nevermind the obvious question of who's file are you ripping/editing and putting a logo on...you know - that old copyright infrigement thing. We will just bypass asking that question for today.