Multiplexing the AC3 with the video

We need to open the specially modified version of VirtualDub called VirtualDubMod which allows us to multiplex the AC3 audio into the XviD-encoded video. First, go to File menu and select Open video file.. and find the AVI you just finished and click Open. Okay, next step is to go to the Audio menu and first select Direct stream processing. After that, select AC3 Audio, again from the Audio menu. This opens a file dialog. Use this to locate the AC3 file you created with DVD2AVI and click Open. Interleaving settingsNow, look at the filename of your AC3 file -- it should tell you some useful information, such as the bitrate of the audio and the delay value for the audio (marked in milliseconds in the filename). Now, go to Audio menu and select Interleaving.... This will open a new window. Now, interleaving settings can't be really told to you, but are more matter of a trial and error -- each movie tends to have different audio characteristics, but we try to ease this pain a little bit by giving some basic values that you should try. For 384kbps 5.1 AC3, try to put 160 into Preload box and 160 into Interleave audio everyXXX box. Then change the selection next to the Interleave audio every XXX box to ms. If your audio is in 448kbps 5.1 AC3 format, try 128ms values for both boxes. Finally, enter the value you have in the AC3 filename to the Delay audio track by XXX ms box and close the dialog box by clicking OK. Next, go to Video menu and select Direct Stream Processing from here as well. After you've done this, go to File menu and select Save as AVI... Now, make sure that your destination directory has appx. 1400MB of free space and then pick a name for the file, something like 'the_movie_final_version.avi' and hit Save. Now, VirtualDubMod starts writing the final file to the HDD. This takes couple of minutes, depending on your harddrive's settings and speed. This final file will include the XviD-encoded video and the original AC3 audio. After you've done this, you should be able to delete all the rest of the stuff you've made during the process from your HDD -- I strongly recommend that you test the final file before deleting anything :-)