Introduction

Welcome to a new generation of MPEG-4 encoding utilities! Forget the times where you had to learn about resolutions and bitrates, worry about finding a suitable splitting point, perform compressibility tests and adjust resolutions accordingly, bother with interlaced and progressive content, etc. AutoGK does all that for you (but it still won't hurt if you get to know the basics of digital video so that you know what goes on behind the scenes). AutoGK is inspired by Gordian Knot, probably the most popular DivX/XviD encoding tool of the past two years, but where GKnot still required long preparation, a lot of preparation and quite a bit of manual interaction, AutoGK automates all this, hence the name. AutoGK is meant to be a one-click tool. While it won't get you from DVD to burned CD in one click (you cannot compare an audio CD -> MP3 ripping program with a video program, video has a lot more variables), it requires almost no manual interaction. For the time being, AutoGK can output only XviD, but DivX5 is going to be added in the future. Since the tool is meant for easy DVD backups that work on a standalone player, it won't allow you to pick options that are incompatible with standalone players (in other words: you cannot configure the codec on your own), and if you're looking for more options, you'll have to wait until AutoGK supports manual configuration via a configuration file (there will not be a GUI for this).

Required Softwares:

AutoGK v2.55
DVD Decrypter v3.5.4.0

A little Info about the Softwares listed above:

AutoGK:

AutoGK (Auto Gordian Knot) is powerful and very easy to use tool for making DVD rips. It was designed for people who know very little about video conversion. It includes everything you need to rip DVD to DivX/Xvid in very easy-to-use interface.

Creating perfect DivX/XviD with AC3 or VBR-MP3 soundtracks is extremely easy, since AutoGK is able to calculate the maxium bitrate that can be used for video to still fit in on the selected CD/DVD size.
Contains following codecs and tools:
VirtualDubMod
AviSynth
BeSweet
DVD2AVIdg
XviD
VobSub
DivX is also supported, but you need to download the codec separately.

DVD Decrypter:

DVD Decrypter is a highly versatile VOB-ripping utility. The software takes advantage of both the DeCSS Plus and VobDec algorithms for looking up and decrypting the CSS encryption. DVD Decrypter is also multi-angle aware, and capable of removing the Macrovision scrambling key, as well as the region code during the ripping process.

AutoGK Guide

Step 1: Ripping the DVD

Enter the DVD you want to back up, then start DVD Decrypter and press the I button on your keyboard.

By default, the longest PGC is preselected. This works for most discs. In rare cases, you'll have several PGCs that have the same (or roughly the same length). If they have the same length, there's usually no reason to worry. If some are a bit shorter, you are dealing with a seamless branching movie. This means, the disc contains multiple versions of a movie (for instance the theatrical cut (what you saw in the movie theater), and the director's cut (usually longer, containing scenes the director thought should be in the movie but the studio wanted cut out because a theatrical release must not be too long). In this case, select the PGC that corresponds to the cut you want to see.

Sometimes, a PGC contains subitems: angles. By default, Angle 1 is selected, which is usually the way to go. Angles are mostly used to have multi-language end credits (Disney and Miramax use those quite a lot). Angle 1 is normally the English release. When in doubt, play the DVD, then press the angle button during the end (or beginning) credits to find out which angle is in the language you want.

Last but not least, series on DVD. Those DVDs usually contain between 3 and 6 episodes on one DVD. The are either all in the same VTS, as different PGCs, or in different VTS sets. Their length should make them pretty obvious to spot (usually 2x, or 4x minutes). You'll have to rip each episode manually be selecting the proper PGC.

Last but not least, access the Settings, click on the IFO Mode tab, and make sure that both options in the File Names section are checked:

Press the big button on the left that has a DVD on it to get started.

Step 2: AutoGK

If you want to play your encoded movies on a standalone using the ESS chipset (check our hardware players forum to find out which players use that chipset), you should install the ESS based standalone component as well. And there's another option that you can install: bitrate spike control. It can help reduce bitrate spikes in the video that might cause playback problems on certain standalones. Then start up AutoGK.

AutoGK's GUI is divided into parts that correspond to the order you have to configure it. First, you have to select the source path, that is the path where DVD Decrypter copied the disc to. You'll also have to provide a path and name for the output file. Make sure the output file resides in a place that has enough free space (if you use one CD, having 1.4 GB free should be enough, for a 2 CD rip, 3.5 GB should do, for a 3 CD rip you need 5 GB to be on the safe side).

As soon as you select the source path, AutoGK will show some additional information about the source below the input directory line.

It is also possible to select File input. In that mode, you can select specific MPEG-2 input files rather than a directory where a ripped DVD resides, or for instance MPEG-2 transport streams that you captured (digital TV). In the future, it'll even be possible to use AVI files (from instance from your DV camera) as source in thi smode.

Step 2 involves the selection of audio and subtitle track. Select the audio track you want to keep from the dropdown list, then do the same for the subtitle track. Note that since AutoGK creates files for standalone players, the subtitles will be encoded as part of the video and cannot be deactivated. As an alternative you could create external VobSub subtitles, which cannot be played on a standalone DVD player, but are playable on a standard PC. If you want a second audio track to be included in the output, just select one from the lower dropdown list.

In Step 3 you select the output size. When doing a regular movie, select the appropriate number of CDs from the dropdown list. When doing a DVD that contains episodes, there are presets that allow you to put a certain number of episodes on a CD: For instance, if you want to put 4 episodes on a CD, select 1/4 CD from the dropdown list. If you don't care about the size, select Maximum Quality (unlimited size) and AutoGK will encode your movie in the best quality possible (note that this doesn't mean DVD quality.. encoding a DVD will always decrease quality unless you're encoding to a lossless format - but those would require more than 100 GB per movie).

If the predefined presets are not good enough for you, you can select Custom size (Mb) and enter the desired output size by yourself. For instance, if you want to put 5 episodes on a 700 MB CD, you'd enter 140 in the size field.

Finally, instead of encoding the video twice for optimal quality given your target size, you can use quality based encoding by selecting Target quality. In quality based encoding, your video will be encoded once using a quality factor on a scale from 1 to 100, where 100 means the quality is as good as it gets and the lower the value, the lower the quality will be. Obviously a lower quality also means a smaller filesize. In quality based encoding there is no control over the output size, you'll get what you get once the movie has been encoded.

This is optional. You can press the Preview button to preview the output. Keep in mind that you will not see which resolution AutoGK will pick unless you force a certain resolution in the Advanced Settings.

If you get more proficient with the tool, you might want to have a look at the Advanced Settings as well.

First we have the Resolution settings. Auto width will leave it up to AutoGK to select the resolution that looks best given your selected size (number of CDs). Or, you could also select either a Minimum width or Fixed width by selecting the appropriate option and using the width field to enter the width. Note that both options could potentially degrade the quality of your output (for instance you could select a width that is too large, and your movie would look better if AutoGK could select a lower width).

When we have the Codec option, where you can decide between the XviD or DivX codec. Use whichever codec you like best. Keep in mind that you have to use the XviD version that comes with AutoGK.

Then, we have the Audio options. The Auto option will use 128kbit/s VBR MP3 audio for 1 CD rips and keep the original AC3 Dolby Digital soundtrack for 2 CD (or larger) rips. If you want to keep the AC3 or DTS no matter what, select the AC3/DTS option. Or you can select the VBR MP3, kbps or CBR MP3, kbps option and set a fixed bitrate. If you don't care about the original soundtrack, I suggest that you set the audio option to VBR MP3, kbps and select a bitrate of 128kbit/s (or 160kbit/s for 2+ CDs).

Finally we have two subtitle options: Display only forced subtitles will process only the forced subtitles on the original DVDs - i.e. the subtitles you cannot switch off. Forced subtitles are often used for dialogue parts which are not in the same language the movie is on. Use external subtitles will use the VobSub format for subtitles rather than encode the subtitles as part of the video. External subtitles cannot be used on a standalone DivX/XViD capable DVD player. External subtitles will be automatically split at the proper position (assuming you're going for more than 1 CD) so you don't have to worry about splitting anything.

Step 3: Codec Settings

We are going to use the Xvid Codec to convert this particular DVD.

Locate your codec from the Start Menu and let's start immediately by changing the Profile @ Level to (unrestricted). This keeps it friendly for folks with no Divx player and different chipset Divx players.

Click the "more" button across from where we just selected our profile. Make sure it's still on (unrestricted). Change the Quantization type to "h.263". And make sure you have everything checked I have checked in this pic:




Now click on the Aspect Ratio tab. It's time to use what we learned from AutoGK about this movie. This particular movie is 4:3. So let's click the display aspect ratio. Now select 4:3. Like this:




Now that we have it selected and hit OK, lets goto "Target Size" and the (calc) button next to it. Here we are able to select the size of video by inputting the length. We are also able to select the audio conversion. This section is also critical in Step 5. Do you want a two disc or one disc encode? Here we have selected a one disc encode. And this is also where the number "845" comes in handy. In this pic:





You'll take notice that I have already plugged the length of the movie in and selected a method of re-encoding the audio. Notice above the audio selection is a greyed out box entitled "Average Bitrate". I have 915 for an average. If you go below 845, you run the risk of VHS quality encode. The audio is a good way to raise the average bitrate. You could select MP3 VBR and maybe get it even higher. But as stated earlier, we're keeping this friendly for everyone's prefered method of playback. Rule of thumb! If the movie is over 1:45:00, you may consider a two disc encode. Below 96Kbps, the audio begins to take on a "can" effect. Sounds like you're listening to it in a can. Very flat, very dull, and just bad show. Now back to Step 5. Select "Predefined Size", drop down to "700MB One CD".

Before we hit ok on our codec setup, let's take care of our quantization options. You'll notice that there is an option to use a preset with Xvid. Our's by now should say "User Defined". Next to that option is a button entitled "more". Click that and this is what you see:





Make sure we have everything set up like so. Anything else will cause macro blocks so bad the video will look like it was seen through an insects eyes. Now click the "Quantization" tab. Make sure you click the "Trellis Quant" as seen here:





Press OK to get back to the main AutoGK screen and press Add Job. This adds the currently configured movie to the job queue.

Now the Start button has become active and you can start the process pressing Start. Or, you could configure another movie, and then also add it to the job queue. Every job you add shows up in the Job queue. You can use the 3 buttons to the right of the list of jobs, to move a job up or down and to remove it.

Once you've configured all jobs, you're ready for the magic. Press Start and AutoGK will start encoding. This will take quite a while, and while AutoGK will also work if you're using your computer while it is working, this will obviously slow AutoGK down.

If you're feeling like configuring a bit more, you can press Control + F9 to launch AutoGK assistant and configure the current job.

AutoGK Assistant

AutoGK Assistant is a tool the allows easy access to all the hidden options Auto Gordian Knot offers.

You can for instance force sound encoding in mono by activating Force encoding sound in mono MP3.

When dealing with a cartoon/animated source, you might want to check Force cartoon mode for XviD to force the special mode for such content that XviD offers.

You can also force IVTC or deinterlacing for hybrid sources by activating option 3 or 4.

In AutoGK Assistant, you can also configure the way credits are treated:

To enable this feature, you first have to enter a Starting Frame, or alternative select a framerate and enter the starting point in hours, minutes and seconds, then press Calc so that the starting frame can be calculated. Then you can check Encode Credits with different settings and use the Quality slider to adjust the quality you want for credits. You can also encode credits as black and white only be checking Greyscale.

You can also reconfigure the way AutoGK does its cropping:

Check Tune auto crop parameters, then you can use the Threshold slider, set the Number of frames to examine to make a cropping decision, and force a frame where the crop analyzation is started (Starting frame for autocrop operation).

In addition, you can force cropping of a given number of pixels using the Force cropping of values.

If you want, you can also override the aspect ratio detection by checking Override input AR and selecting the desired AR.

Then we have a few options for digital TV sources:

Check Reduce FPS for 60/50 fps HDTV progressive sources to reduce their framerate to "standard" framerates, and pick which framerate your output is going to have.

You can also configure the Treshold for duplicate detection, which AutoGK uses to decide if a source has duplicate frames that can be safely dropped.

Then we have a couple of options on deinterlacing, resizing and filtering:

If deinterlacing is used, you can check Tune KernelDeInt filter threshold to configure the filter to use the threshold you set using the Threshold slider.

If you're a fan of ITU resizing, check Force ITU resize method.

Checking Force sharp MPEG matrix for XviD forces AutoGK to use the MPEG quantization matrix in XviD.

 

Finally, a few more settings:

Display VCF scripts for VDubMod in the logs can be useful if you're encountering problems - the VCF script might help detect the cause of those problems.

Resizes and places burnt-in subs properly can help if you have subtitles encoded in the source video. It ensures that they'll also be visible in AutoGK's output.

Correct color if needed enables a color correction filter.

Detect and force 4:3 AR if close to that aspect is used to force a 4:3 input DAR in case the input has a similar but not exactly a 4:3 aspect ratio.

Finally, Enable standalone support and checking the chipset your standalone player has, can be used to enforce settings that are certainly compatible with your standalone DVD player.

 

If you're not using your PC, and want it to shut down once the movie has been encoded, check Shutdown when done.

Last but not least, AutoGK will report what it is doing at the moment in the Log window. The same information is also stored in a file called moviename-agk.log that is in the same directory as your output file (moviename is the name of your movie as set in step 1, in this case the logfile would be called trainingday-gk.log). You'll need that logfile in case something goes wrong. Don't make a report without that file!

If you have selected an output size larger than 1 CD, the output file will be split at the proper position. The split files will be called moviename.CDx.avi. In our example, we'd get two files: trainingday.CD1.avi and trainingday.CD2.avi.

For problems and support, please turn to the Gordian Knot forum.