I need some insight as to why sometimes when I convert a video to MPEG, the audio is out of sync on the output file. Sometimes it is only slight, and is consistent. Other times, the video is fine for a while and then all of the sudden it becomes out of sync for the remainder of the video. In each case, these defects are not present in the source file. The re-encoding introduces the problem. I have seen it happen with WinAvi Video Converter, Convertxtodvd, and mainconcept mpeg encoder. It is maddening. It all seems pretty random, but I have noticed that WinAvi is more likely to spit out an out of sync file when converting to VIDEO_TS (DVD) than when converting to VCD. What are the typical reasons for this problem? What can I start doing (or not doing) or checking?
If constant throughout the video: Before you encode the file, run it through AviMux_Gui: http://www.alexander-noe.com/video/amg/ (vl 17.7-binary)Drag your original file into the top window, highlight it and select generate data. In the lower window, select audio and any delay will appear to the right in ms. If other than 0 appears, select start, place and name your new file as you wish and encode it. Only takes a minute or two but doesn't help on gradual sync issues. The original probably won't show any sync issues on your pc.
if you are converting avi to dvd this might help. you will have to download virtualdub. i found this thread. Hi, am using Winavi video convertor program to convert my AVI files to dvd to play them on my dvd player. I didn't have any problem when i burned my first movie, but the second time i burned another movie the sound in the film comes before the picture which is really Ridiculous. Does anyone plz know why this happens and how can i solve it and IF there's another better program to use instead of this stupid program. Your Problem has to do with the Fact that most Movies you download off the Net use "VBR Mp3" audio which is a Format that will Allways go out of Sync after converting to another Format ... So to Solve this Problem you Must Decompress the audio in your AVI files before you attempt to Encode the File.... You can decompress the audio in your AVI file by useing "Virtual-Dub"... What you do is Run V-Dub and then Load in your AVI file (which will give you an error message right off the Bat because the audio is VBR MP3, Just Click OK)... Then go to "Video" and set it to "Direct Stream Copy" and then go to "Audio" and set it to "Full processing Mode" and then go to "File" to "Save as AVI" and give the File a Name and Save it and in a Few Minutes you will have a New AVI File with Uncompressed Audio that will Not (Hopefully) go out of Sync after encodeing.... The New AVI file will Be Much Bigger than the Original because the audio is Decompressed But that will Not affect the Size of the File when encoded to Mpeg-2/DVD.... Cheers
Not always. ConvertXtoDVD handles vbr audio very well if it's been encoded properly. As mentioned by mistycat AVI-Mux GUI will usually correct problems, while still leaving it as VBR. I think there is more to it than just the delay as I've noted that ConvertX can handle delays. It seems that 'bad' in the read out is even more telling (or does a delay always trigger the 'bad' tag?). That's a good method, especially for those who use NeroVision Express, but I've found that it doesn't always produce in sync audio in the new AVI. I have an AVI that AVI-Mux GUI shows as having a delay of 1368ms and is 'bad'. Running it through ConvertX it does pick up the delay and resultant VOB seems fine. But running the same AVI through Vdub and creating a PCM audio AVI, it's now out of sync. The original AVI plays fine as an AVI.
