DivX5 in Gordian Knot

Go to the preview window and Select Save & Encode from the file menu.

Now you have quite a lot of options:

Gordian Knot will select a resizing filter for you depending on the bitrate. If you don't like its selection modify it. Lanczos is a good choice unless you have very low bitrates (> 2h20 movies, or multiple audio tracks). In the latter case simple can be a viable solution.

Then we have some more filtering options.

First of all the noise filter. If you think your source is very noisy you can use one of those filters. Personally, I'm not a big fan of such filters so I never use them.

Then we have the field operations.

If DVD2AVI showed your source as interlaced PAL and the preview was interlaced you enable Separate Fields here or FieldDeinterlace here (the latter is slower but of better quality).

If DVD2AVI showed your source as NTSC FILM below 95% you enable Inverse Telecine here. In all other cases set Field Operations to None.

The next option concerns subtitles and can be skipped if you have no subtitles.

Then the subtitles. Here you are at a crossroads: If you want permanent subtitles press the Select VobSub Files button and select the ifo file from the 2 files that VobSub has created for you. If you prefer to have subtitles that you can switch on and off during playback and in multiple languages don't select anything here, your subtitles are already properly prepared. The after Borders option is for VCD/SVCD creation only and does not concern us.

And last but not least the compressibility check.

It's possible to run a short first pass to find out the optimal compressibility of a movie (and make an even better resolution choice). Turn the Compressibility check on and set it to 5%, then press the Now button, wait for a few minutes until GKnot comes up again. The Edit button allows you to edit the AviSynth script prior to performing the check but only experienced people should touch that. Same goes for Codec settings which allows you to manipulate the codec settings used for the compressibility check.

Once the check is done you'll see a message in the titlebar of the preview window:

Now check the lower line of values shown in the screenshot below:

The compressibility check gives you a rough indication of how good a movie can be compressed. The 3 values shown above are related as follows: the 0.338 is the value that the compressibility check returned. If the Bits/(Pixel*Frame) the first value, right above the Load button matches this value you have perfect quality, going for a higher value would be overkill as the movie wouldn't look any better.. The limit of the codec has been reached. The 41.7% value tells you the relationship between the optimal case and what you're going to get at the currently selected resolution. 60% or higher will pretty much guarantee that you'll get pretty good looking results. Going over 80% is a serious overkill and you should rather increase the resolution. Values in the range of 50-60% still look pretty good and 40-50 is still OK, especially when you activate B-frames. The darker a movie gets and the cleaner the source the more you can compress a movie. Using B-frames certain movies will look good even at a 0.12 Bits/(Pixel*Frame value). Once the value is in the acceptable range set the trim option to Both (enc. credits separately).

This way the end credits will be encoded in constant quality mode at a really low bitrate and then appended to the main movie.

Now press the Save&Encode button which will bring up to save file dialogues (just click OK in both of them) and then you'll get to the encoder tab:

First you'll get a stats screen with the current options. Keep in mind that since GKnot does the audio encoding for you the final bitrate won't be correct and the audio size won't be either.

Then the encoding options. The default values are good. Re-calculate bitrate if needed should be checked in any case, as should append credits. Also check delete intermediate files so that only the final AVI remains in the end. Finally you can change the end credits compression levels if you want to.

If you activated IVTC the IVTC in avs -> correct Frame Count. will not be grayed out and you have to check it.

Then you can also reconfigure the codec. When you first installed GKnot you have probably set up some codec defaults (at least if you followed this guide). So normally all you'd have to do now is set the number of passes and you're done.

The use of more than 2 passes is still not really known so do your own experiments and then decide on the number of passes to use. Or just leave it at the default of two. It worked for DivX prior to 5.03 ;) And if you like to make some adjustments to the codec settings, press the appropriate button to re-configure it.

Then go to the audio1 tab:

All you have to do here is check Just Mux and you're all set. If you have a 2nd audio track now go to the audio2 tab and do the same.

Now go back to the DivX5 encoder tab.

Pressing the Add Job to Encoding Queue button will add the job you just set up to the queue. You'll then be asked whether to start encoding or not. This allows you to add multiple jobs to the queue and then encode them all without any further manual interaction. It's of course also possible to add jobs while the encoding is already ongoing by simply starting to follow this guide from the top again (of course you must not close GKnot and do everything in the already running instance of GKnot).

From now on you won't have to do any manual interaction until your AVI is finished. You can even safely work on your PC while it's encoding, just make sure you don't kill any windows that suddenly will pop up. That's GKnot launching different programs on its own.

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This document was last updated on April 24, 2003