Best video quality on VD


zboy9

かっこいいね。
Joined
Feb 16, 2003
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Age
35
I use Virtual Dub and lately I have gotten crap results. I have the bitrate at 126 and decimate by three, my max quan. is at 30, my min at 18. I thnk it has to do with those two numbers. Does anyone know what to do to get the best video quality results? Thanks
 
What are you trying to encode? Those settings ought to be OK for cartoons, but not for, say, live action. Personally, I use 16 min, 26 max for most stuff - better quality if I can be bothered I go to 13/4 and 22/3 but those are substantially bigger files. But 18/30 is low quality - although probably watchable. You could just about make out that there was some action going on in smething like The Matrix, for example. But you wouldn't be able to see what it was.

Bitrate actually makes very little difference, odd as that may sound. I've encoded stuff with a bitrate of 80 before and had it look as good as at 120 or so - its the post-processign setting that makes the difference - be sure to have it at max. Unfortunately, using lower bitrates doesn't always decrease the size either, so its something to fiddle with. My usual is ~90, although I usually test stuff to see if its OK (and if I can get it smaller without quality loss) down to azbout 60. Usually there's no point.

Decimate by 3 only if that's the only way to get it below 10fps... if at all possible use 2 as its a lot smoother; well worth the extra space (unless its something like, say, Shadowskill, in which case decimate by lots since the original ain't exactly smooth).


Other than that, I can't really give you any tips... try a few filters, perhaps - remember to re-size with either Precise Bilinear or Lancoz 3 (both are pretty good, bilinear is slightly faster, lancoz is marginally less blury, but not so as to make it look significantly better). There's lot of filters out there, and the smoother you can get it to start with prior to encoding, the smaller the output *should* be (easier to round i you're aiming at pure red than a patchwork of reds) so especially worthwhile again with cartoons.



To give you an idea of what you should be looking at, I got a Harry potter 2 DVD-rip down to 90megs. Evolution, with slightly lower quality, went to about 55. Thundercats the Movie, though, since its a cartoon got down as far as ~30 without looking bad.
 
Thanks for the speedy reply. I will try some of that.
 
I tend to use decimate by 2 for PAL and NTSC 23.9 /w 3:2 pulldown, and decimate by 3 for NTSC 30fps.

For bitrates, I use anything from 30-50kb/s
 
Personally I use max quantizer 20 and mix quantizer 2 and fiddle from there. Choosing the quantizer is the most important part of the video encoding process. The quantizer controls how fine the encoder codes the video sequence. Basically for a particular frame, the smaller the quantizer value, the better quality, but higher bit consumption. Larger quantizer values yield lower bit consumption but lower quality as well. If you choose the max and min values to be the same, then you get a somewhat constant qualtity but that leaves no room for the encoder to adjust the bitrate. Personally, I've used 20 and 2 for my settings (sometimes I tweak the max one down) and I've been very happy with it.

The bitrate for me did make a difference. I went from 70 to 115 and I saw quite a large difference. Personally, I sacrifice disk space for quality and with the settings I choose, I can fit about 1 hour onto my smc card (about 3 simpsons episodes). If you wanna save space, I'd recommend using a smaller bitrate than I do.
 
Heres what i use this setting got a realy good quality 2 hours 15 mins of The Matrix in to 78 MB
(thanks to M^4 for the brightness/contrast setting and pointing me to the right version of Vdub[1.5])

Put this in notepad save it as a *.VCF file and load it under load setting in vdub


VirtualDub.audio.SetSource(1);
VirtualDub.audio.SetMode(1);
VirtualDub.audio.SetInterleave(1,500,3,0,0);
VirtualDub.audio.SetClipMode(1,1);
VirtualDub.audio.SetConversion(11025,0,0,0,0);
VirtualDub.audio.SetVolume(1552);
VirtualDub.audio.SetCompression(85,11025,2,0,4000,1,12,"AQACAAAA0AABAHEF");
VirtualDub.audio.EnableFilterGraph(0);
VirtualDub.video.SetDepth(24,24);
VirtualDub.video.SetMode(3);
VirtualDub.video.SetFrameRate(0,1);
VirtualDub.video.SetTargetFrameRate(100000,10000);
VirtualDub.video.SetIVTC(0,0,-1,0);
VirtualDub.video.SetRange(0,0);
VirtualDub.video.SetCompression(0x78766964,0,10000,0);
VirtualDub.video.SetCompData(316,"0H4BANAHAAAKAAAAFAAAAJABAAAUAAAACgAAAAUAAAAAAAAAVQAAAAAAAAAAAAAAAAAAAP////8BAAAAYzpcZGl2eC5sb2cAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA==");
VirtualDub.video.filters.Clear();
VirtualDub.video.filters.Add("brightness/contrast");
VirtualDub.video.filters.instance[0].Config(22,17);
VirtualDub.video.filters.Add("resize");
VirtualDub.video.filters.instance[1].Config(320,240,3);
VirtualDub.audio.filters.Clear();
VirtualDub.subset.Delete();
 
Once I've watched Matrix 2 (this evening!) I'll get my stored copy and convert it, so ppl who can't use VDub or are having problems can watch it anyway :)
 
yeah, I feel you on the Matrix Reloaded, I've got it ready and converted for use right when my GP32 drops on the doorstep. I hope the new Fnes comeso ut before i get it, maybe even the new Snes emulator :)
 
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