Avisynth on Virtualdub too large

[mrcoolekin]

I got the new version of DirectShow, Avisynth, and VirtualDub.

I place the file in VirtualDub and get the file info:
Video - 836 kbps
Audio - 128 kbps
File Size - 170MB

================================================== ===========

When I put a avisynth script in the VirtualDub like this:
DirectShowSource(C:\My File)
BilinearResize(640,436)
AddBorders(0,22,0,22)

When I look at the file info for that particular script I get:
Video - 88385
Audio - 1536

================================================== ===========

When I try to save the Avi, the file is about 15GB. Is this a known issue or something. Is there anything I can do to correct this?

[mats.hogberg]

Yes, you have to select and configure the compression in VirtualDub. Your 15 GB file is most likely uncompressed.

/Mats

[AlanHK]

Avisynth is a frame server -- it decodes a file and presents it to the client (in this case, VirtualDub) uncompressed on demand. So you have to compress the output unless you want a gigantic file.

Somewhat like doing a screen capture of a JPEG displayed in an image viewer. By default you may get a huge BMP file, if you want a JPEG you have to explicitly choose that.

[Alex_ander]

And in both cases VDub reads correct info, e.g. for audio decompressed by AviSynth you have:

48kHz x 16bit x 2channels=1536kb/s

[mrcoolekin]

Hey thanks, I never knew that until I started to do a "direct stream copy" of the file. I just wanted borders with the same quality video. Of course even though avisynth throws VirtualDub an uncompuressed version of the file, when I recompress it, my quality will go to crap right???

My video file was already an xvid video, but Virtualdub wouldn't process all the frames cause it said it was bad frames or something. After that I started using avisynth. Is there another way to input the video in avisynth/virtual in the compressed version so I could do a "direct stream copy"?

[AlanHK]

Hey thanks, I never knew that until I started to do a "direct stream copy" of the file. I just wanted borders with the same quality video. Of course even though avisynth throws VirtualDub an uncompuressed version of the file, when I recompress it, my quality will go to crap right???

Not so bad probably. You might see some artifacts as you view the Avisynth output in VirtualDub. If you encode that to a new AVI, you'll get those and some more.

Simplest to just encode a few minutes at different compression settings to see what difference they make.

[mats.hogberg]

If you want to add borders, the video has to be recompressed. Only type of edit you can do with direct stream is to cut or concatenate video.

/Mats