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DVD to XviD 1.x using Gordian Knot

Gordian Knot started out as a bit-rate calculator, and has now turned into one of the best DVD to DivX/XviD conversion tools around.

Below are instructions on how to convert your DVDs to XviD 1.x (1.0 RC 4 at the time of writing) using Gordian Knot. If you want to convert your DVDs to DivX 3.x or 5.x, please refer to this page.

You should download the following software, which are required for this article :

  1. Install Gordian Knot - Gordian Knot is a large package that comes with many bundled software - you should leave the default installation alone, unless you know what you are doing. Also install any patches that are available (see Gordian Knot download page for additional instructions). There may also be separate rip-pack and codec-packs for Gordian Knot on the official download page, so make sure you install these packs if you haven't done so before.

  2. Setting up Gordian Knot :
  3. Start Gordian Knot (GKnot) ...

  4. Gordian Knot can save the settings you use in any particular conversion session. If you want to save your current settings, go to the bottom right hand side of the main GKnot screen and use the pull down option box to select a free slot to save your settings. Then click on the "Rename" button to rename the slot with a more suitable name.

    GKnot - Save

  5. We'll now rip the DVD ("DVD rippping" definition : copy the DVD to your hard-drive, without the DVD copy protection screwing up your files). Go to the "Ripping" section by clicking on the "Ripping" tab, and click on the "SmartRipper" button to start the DVD ripping software SmartRipper.

    GKnot - SmartRipper

    1. In SmartRipper, click on the "Target folder icon" to select where you want to rip to. Please select a hard-drive that is large enough to hold the movie you want to rip (5 to 10 GB of free space, depending on the length of your movie). For this tutorial, I am only ripping Chapter 19 of the Back to the Future III DVD, but if you to rip the entire movie, don't touch any of the SmartRipper settings, apart from changing the target directory. Then click on the "Start" button to start ripping - this can take several minutes, depending on the speed of your DVD-ROM drive and also the length/size of the movie you are ripping. Close SmartRipper when the ripping has been completed.

      GKnot - SmartRipper - Chapter 19
      GKnot - SmartRipper - Target
      GKnot - SmartRipper - Start

  6. We'll now make a DVD2AVI project file. Still in the "Ripping" section, click on the "DVD2AVI" button to start DVD2AVI. Please follow this DVD2AVI guide to find out how to make a DVD2AVI project file. Also take a note of the "Statistics Window" results you get when playing back the movie in DVD2AVI - the properties you should remember are "Aspect Ratio", "Video Type" and "Frame Type". You can close DVD2AVI after you have finished saving the project file.

    GKnot - DVD2AVI

    Now load in your newly created DVD2AVI project file (.D2V) by using the "Open" button on the bottom left hand side of the screen - this will open a new window showing the movie - don't close this window, but you can minimize it. GKnot will read the project file and automatically set the number of frames and frame rate.

    GKnot - Open DVD2AVI Project File

  7. Now go to the "Bitrate" section. Select the "XviD" option. Also select the number of CDs you want to span the movie across. You can also manually change the file size, which is what I have done (set to 65 MB for Chapter 19) since I am only encoding a section of the movie.

    GKnot - Bitrate

  8. Now change the Interleaving option. Leave the "Calculate Frame-Overhead" option selected, as this will prevent your movie from becoming larger than the separate video and audio files added together (due to overhead). Also select the audio options - "1x vbr-mp3" is a good option if you want 1 audio track encoded using variable bit-rate MP3 (best quality VS file size ratio).

    GKnot - Bitrate - Interleaving

  9. Now we configure the audio option. Choose a bitrate from the drop down menu. There is also another option ("Audio B") for selecting the properties of the second audio track, if you wish to have one.

    GKnot - Bitrate - Audio A

  10. Now go to the "Resolution" section. It is here we'll choose the resolution/aspect ratio of the movie. We'll first crop the movie first, which is simple to do under GKnot - just click on the "Auto Crop" button and select the "Smart Crop All" option.

    GKnot - Resolution - Cropping

  11. You should select "PAL" or "NTSC" and then "anamorphic", "non-anamorphic" modes for the "Input Resolution" and "Input Pixel Aspect Ratio" - you should know what to select here by remembering the values shown in DVD2AVI's "Statistics Windows" (back in step 5). You can go back to the window that was opened when you loaded the DVD2AVI project, select the Preview ("FrameNo") window to see what the cropping and resizing will look like.

    GKnot - Resolution - Aspect Ratio

    GKnot - Preview - View

  12. We can now select the actual resolution of the output XviD movie, made easy by using the big slider. Now look at the bottom of the screen, the "Bits/(Pixel*Frame)" section, and observer the rating. If this rating falls below 0.17, then you are going to have a pretty bad looking video. If your rating is above 0.30, then this could cause the file to be oversize (over the size you selected earlier).

    GKnot - Resolution

    GKnot - Bits/(Pixel*Frame)

  13. Subtitles can also be added to the movie using VobSub. Instructions for this coming soon ...

  14. Video and Audio encoding :
  15. Now that GKnot has been setup, we can finally start with the encoding process. But before we can hit that magic "start encoding" button to sit back and wait, there are a few more options we need to set ...

  16. Bring up the preview window again, and click on the "Save and Encode" button. These are the options you need to set :
    • Resizing : - Leave "Selected Output Resolution" selected

    • Resize Filter : - Bilinear makes everything a little blurry. Bicubic can make things very sharp, but jaggies can be apparent. The best option to choose is the middle ground between the softest and sharpest option, which is the "Neutral Bicubic".

    • Field Operation : - This option is not needed by all videos. If you can remember back to when you saved the DVD2AVI project, the "Frame Type" that I reminded you to remember earlier on becomes important here. If the "Frame Type" is "Interlaced", then you need to enable "Fast Deinterlace" here - otherwise, set it to "None".

    • Noise Filter : - Unless your source video is very noisy, you should turn off this filter as it would decrease the video quality. Most DVD movies don't have much noise anyway.

    • Subtitles : - Only use this option if you want the subtitles to be burned permanently into the AVI files (can't be removed at a later date, no matter what you do). If that doesn't appeal to you, then you can use DirectVobSub to playback the subtitles files you created earlier, and you can choose to turn it on and off whenever. If you want burned in subtitles, click on the "Select VobSub Files" button and load in the ".ifo" file that VobSub created for you (not the ".ifo" file you ripped from the DVD).

    • Compressibility Check : - Here is one last step to ensure you get the maximum quality out of your XviD movie. What this option does is to quickly scan through your movie and determine how good it can be compressed at. This should let you know whether the file size/resolution settings you set earlier on are suitable. To use this check, enable the "Use" option and press the "Now" button - after a short while (VirtualDub is loaded to scan through the video), you should be returned to the preview window (it will say "Compressibility Check: Finished" on the Window's title bar). Check the "Bits/(Pixel*Frame" section on the bottom of the GKnot window to see the results of the check.

      The "%" value means the ratio between your currently selected Bits/(Pixel*Frame) value and the suggested value. The equation Bits/(Pixel*Frame) should let you work out what you need to change in order to increase/decrease this value (eg. increasing file size/Bits increases the value, whereas increase Pixel or Frame size, decrease this value).

      Ensure the "%" value returned by the Compressibility Check is between 60% and 80% for maximum quality. Going over 80% is not going to increase the quality too much, so it's not worth doing it. Falling below 50% will mean poor quality. To modify the "%", you should try changing the file size (step 6) and/or resolution (step 11).

    • GKnot - Save & Encode

  17. Don't worry ... we're nearly there. Press the "Save & Encode" button (shown in the picture above) and choose a name for the AVS that will be generated. This should bring up the following screen :

    GKnot - Save & Encode - Encoding Control Panel

  18. We now configure some of the XviD 1.x specific options in the "XviD" section. Press the "First Pass" button - this should bring up the XviD Codec Configuration screen :

    GKnot - Save & Encode - Encoding Control Panel

    You'll now need to setup XviD 1.x's first pass settings - I have already written a reference guide to setting up the XviD 1.x codec for two pass encoding, and you can access this guide by clicking here.

  19. Now go to the "Audio 1" section. Use the "Select" button to load the AC3 file DVD2AVI saved earlier on. If you want to keep the AC3 audio, select "Just Mux", otherwise, select "MP3, custom Parameters". Most of the options will be filled in for you automatically, but you do need to set the "Transcoding Parameters". Use the drop down list to select your options (note : "--alt-preset 160" means the MP3 will have a bit-rate of 160). Repeat the same for "Audio 2" if you have two audio tracks.

    GKnot - Save & Encode - Encoding Control Panel - Audio 1

  20. We're nearly there now ... Return to the "XviD" section and press the "Add Job to Encoding Queue" - you should be prompted to either start the coding now, or add more jobs to the queue before you start. You can always add to the job queue afterwards, if you wish. If you choose to start the job now, GKnot will start working, calling up different programs and in a short while, your encoding should be finished - during this time, you do not need to do anything, and you can still use your computer for other tasks.

    GKnot - Queue

  21. Finished !!

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