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  1. Ok guys, I've done a little more research and concluded that sceners definitely used the following individual tools:

    - DVD Decrypter (if necessary)
    - DVD2AVI / DGIndex
    - NanDub / VirtualDubMod + AviSynth
    - Xvid codec
    - LAME MP3 encoder

    I've also learned that VDM presumably as of version 1.5.x does support VBR (ABR) streams if you tick "By default try processing MP3 VBR streams like Nandub" in Preferences, which is hardly mentioned anywhere. Until then they would use NanDub strictly for muxing video and audio streams, which is why you can see the following in MediaInfo output:

    Writing application : Nandub v1.0rc2
    Writing library : Nandub build

    Still, you can't produce ABR streams directly in VDM (the "correct" ones I mean), you have to extract the original audio track and convert it to MP3 using LAME typically with "-q 2 --abr 128" parameter and add it to the stream list before running 1st and 2nd passes. 1st to calculate the output file size with regard to audio size and 2nd for muxing while encoding video stream. Also, the reason why most sceners went for ABR as opposed to CBR and "vanilla" VBR is because it's the "smartest" and most compact mode, albeit a bit compromising in terms of compatibility or so they say. On the bright side, it will save up some bitrate for the video.

    The rest is all about AviSynth filters. In fact, pretty much ALL modifications apart from pure re-encoding such as cropping, resizing, deinterlacing etc were done via AviSynth, never in VDM itself, because the latter doesn't even know how to address AR correctly e. g. if the source is 16:9 it will produce 4:3 output. Incidentally, that's also how Gordian Knot and AutoGK operate, though they won't let you use your own filters unless you pre-edit .avs files or produce audio streams with custom parameters beforehand. That's how I know sceners never used any of that.

    Of course, it would've taken me much longer to discover all that if not for your kind input, guys. I also came across this ancient thread, which, seriously, I should've seen a long time ago. However, it's still not as complete as it looks and it doesn't mention some of the delicate bits I've shared with you just now.

    Ok, so we have finally debunked it... not. The million dollar question remains and it's AviSynth filters. Which ones to use? Unfortunately, there is no way of knowing which combinations of those were applied by sceners as it's obviously not the kind of information you can retrieve from files. My major concern are 3 things:

    - Deinterlace
    - Resize
    - Smooth/Deblock/Denoise/Deband

    With regards to the first thing I'm completely clueless as I have little understanding of what interlaced content is other than a bunch of stripes appearing on motion with deinterlacing off in your player. But to be brutally honest, I don't really care much for what it is, I just need a good remedy for it. I know some filters just work like KernelDeInt() or TomsMoComp(), but I also want to know in what way do they differ and which one would make an optimal choice for most occasions. I've tried both and I can't seem to notice any difference, but I know it's there however subtle. I would like some input on this, please.

    Resizing seems easier as at least some of those methods seem to differ dramatically. I came to know that Lanczos & Lanczos4 are not recommended for lower bitrates as their sharpness would in many cases lead to "ringing". Incidentally, that's one of the reasons why I dislike AutoGK, it maxes out on this thing and the output is always terrible. I have no idea which filters it uses, but probably something even sharper than Lanczsos / Lanczos4. I will have to see inside .avs it creates later. Anyway, after a few experiments I ended up being in favor of Bilinear and Blackman methods. First one seems like something most sceners had applied as it also does a very good job at smoothing the picture at the cost of little detail but with little to no ringing at all. It's great, though it's hardly ever praised. Blackman is something in-between Bilinear and Lanczos, it smoothens out the picture while keeping it sharp more or less. I've also tried Spline16/36/64, but failed to notice any substantial difference to what Lanczos does. So, I'm pretty convinced sceners mostly used either Bilinear or Blackman depending on the type of source, duration and target filesize. None of this is mentioned ANYWHERE. Still, if you have any advice regarding this particular aspect I'm all eyes.

    Now, probably the toughest one as there is a myriad of different methods, filters and miscellaneous mods. They are also used in combinations which typically involves very delicate tweaking, depths, thresholds etc. This is way over my head. My other issue is that I can't always tell what's wrong with the picture, I can only see that something is off. Granted, I know what ringing and banding is, but what is "noise"? And how would "deblocking" help? Are these synonymous or not? I really need to know more about this, else I may have to dispense with it and stick with resizing filters alone, which, for all I know, will not produce 100% desired result. My rips are pretty good now, much better than they were years ago when I used AutoGK. But when I compare them to scene ones I can tell something is still missing. Something very delicate and it's definitely a combination of things. I could keep on experimenting I guess, but I'd rather I didn't spend too much time on this.
    Last edited by Damiano; 25th Mar 2020 at 15:56.
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  2. Originally Posted by Damiano View Post
    I have also discovered some new stuff here. First off, there is this much more profound tool than Gordian Knot, which still receives updates: MeGUI. It seems pretty complex and also better in a handful of ways. Anyone got experience working with it?
    No way you can produce a better divx quality backup of a DVD Video with another tool than Gordian Knot
    Firstly because it is not the software which determines the quality of the backup but the codec used, here the Xvid or the DivX.
    Gordian Knot lets you access the codec settings which many software programs do not allow.
    Do not bother too much the brain with the different settings of the codec because it is contradictory with a backup of a video weighing 4 or 8 GB in less than 1 GB
    Make a backup of 1400 MB, we always stay in nostalgia because it corresponds to the size of 2 CD
    The only software that I prefer to Gordian Knot is Xvid4PSP because the backup is done in one click with access to the codec settings and the possibility of applying filters ....
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  3. No way you can produce a better divx quality backup of a DVD Video with another tool than Gordian Knot
    If you had read my previous post you would know that the quality doesn't always depend on codec settings, there's quite a bit of AviSynth scripting involved, which alone can do plenty of magic. The truth is, Gordian Knot while being more flexible and less intrusive than AutoGK still cannot produce files as good as scene ones. There is no reason it should. And MeGUI at least offers more user-friendly control over these things.

    Speaking of AutoGK, I decided to give it another go just to generate the .avs file and here is what I discovered:

    LoadPlugin("C:\PROGRA~2\AutoGK\DGMPGDec\DGDecode.dll")
    LoadPlugin("C:\PROGRA~2\AutoGK\filters\autocrop.dl l")
    LoadPlugin("C:\PROGRA~2\AutoGK\filters\RemoveGrain SSE3.dll")

    movie = mpeg2source("F:\...")
    cropclip = autocrop(movie,mode=0,wmultof=4,hmultof=4,samples= 10,aspect=0,threshold=34,samplestartframe=0,leftad d=0,rightadd=0,topadd=0,bottomadd=0)
    fixed_aspect = 1.18518518518519
    c_width = width(cropclip)
    c_height = round(height(cropclip) / fixed_aspect)
    input_par = float(c_width)/float(c_height)
    input_par = (input_par > 1.4) || (input_par < 1.25) ? input_par : (4.0/3.0)
    out_width = 608
    out_height = round(float(out_width) / input_par)
    hmod = out_height - (floor(out_height / 16 ) * 16)
    out_height = (hmod > 4) ? (out_height + (16 - hmod)) : (out_height - hmod)
    new_aspect = (float(out_width) / float(out_height)) / fixed_aspect
    autocrop(movie,mode=0,wmultof=4,hmultof=4,samples= 10,aspect=new_aspect,threshold=34,samplestartframe =0,leftadd=0,rightadd=0,topadd=0,bottomadd=0)
    LanczosResize(out_width,out_height)
    RemoveGrain(mode=2)

    As you can see, it does use some plugins, which though are nothing special. Also, I was wrong about "sharper" filter, it's just good old Lanczos after all. As for smooth/deblock/deband etc it's only RemoveGrain, which probably doesn't even do a lot. This would explain why the output is so mediocre, other than computing resolution/aspect and performing autocropping there is nothing of great value here.
    Last edited by Damiano; 25th Mar 2020 at 19:36.
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  4. What determines the quality of a compressed video is Video source, Video resolution, Video bitrate, Video framerate, Video codec used.......This is valid for all video compressed.
    With Avisynth filters you can increase the quality of some videos backups with filters like denoise, degrain, deblock.....But the settings that will be valid for a video will not be valid for another....
    Do you really think sceners uses filters when they backup a DVD ?

    @Damiano "If you had read my previous post you would know that the quality doesn't always depend on codec settings, there's quite a bit of AviSynth scripting involved,"

    Thanks so much ......I was a member of an old French team who ripped hundreds of DVDs and made them available on DC ++ with our own hubs.
    All used Nandub with the DivX3.11 codec, VirtuaDub with the XviD codec from Koepi and the DivX5.02 pro and is famous spyware Gator
    After we used VirtualDubMod, FlasKMPEG, FairUsePortable, GordianKnot, RIAM, DVDx, XMPEG, Vidomi, Catalencoder, Neodivx, drdivx2, SimpleDivX, Divx Video Duplicator......
    We have used the filters very little for the only reason that we are never sure of the final result. Some used the cropping function, others no, because some players displayed the video in wrong aspect ratio, some rip in 700 MB, others in 1400 others in 712 because video could be burned on a CD with the overburning function of Nero, some encoded the credits at 20% of the bitrate used for the rest of the video....Thanks again
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  5. Member
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    Wow, DC++, I was a user myself almost 20 years ago.
    I think almost all mainstream commercial DVD's were "good enough", they didn't really need
    filtering, except typically IVTC/cropping.
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  6. What determines the quality of a compressed video is Video source, Video resolution, Video bitrate, Video framerate, Video codec used.......This is valid for all video compressed.
    And duration.

    With Avisynth filters you can increase the quality of some videos backups with filters like denoise, degrain, deblock.....But the settings that will be valid for a video will not be valid for another....
    Well yes, obviously, which is why one must have options.

    Do you really think sceners uses filters when they backup a DVD ?
    Honestly, I can't be 100% certain but I thought some rips look too good to be just direct re-encodings from a DVD. But then a lot of them were made before 2005, which means filtering wasn't a big thing yet, so maybe you have a point, after all.

    Thanks so much ......I was a member of an old French team who ripped hundreds of DVDs and made them available on DC ++ with our own hubs.
    Sorry, I didn't mean no disrespect and I also wasn't aware of your experience.

    We have used the filters very little for the only reason that we are never sure of the final result.
    Thank you, that's very good to know.

    Wow, DC++, I was a user myself almost 20 years ago.
    You will probably laugh but I started using it just 2 years ago. It's not like I hadn't known about it, just never got around to it until then. Besides, I've been using emule since 2006 and had little need for another p2p network
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