Audio hiccups after joining files

[Tamiil]

I do most of my editing on virtualdub, but I ran into a curious problem. Whenever I try to join little video files together, that I've edited out of one huge file, I get these weird and loud hiccup or tick noises at the start of the next video that I've joined. Is there solution to this? As I've understood, avisynth is the most powerful editing tool, so I was hoping there's a solution using this. I've tried FadeIn, but it doesn't quite help. I also know very little about avisynth scripting, so could someone please give me a piece of code to use?

[IanB]

The hiccups are caused by joining the audio without regard for the edges being at zero crossing points.

Using FadeIO0() is a solution, but you want only a 1 millisecond fade in and out not a whole frames worth, i.e. 30 to 40 milliseconds.

A functions like this can allow silent joins.Function CleanAudioEdges(clip In) {
KillVideo(In) # Remove video so fade fps option is active
FadeIO0(1, FPS=1000) # 1ms edge clean
Return AudioDub(In, Last) # put back input video
}

AV1=...Source("clip1...").Trim(123, 456).CleanAudioEdges() # Do any trims before clean
AV2=...Source("clip2...").CleanAudioEdges()
AV3=...Source("clip3...").CleanAudioEdges()
...

AV1 ++ AV2 ++ AV3 +++ ... # Use Aligned splice operator
...

[Tamiil]

Thank you a ton IanB. Although it wasn't your script per-se that was my solution. I tried your script, but I've always joined files via virtualdub, and so I did it again this time. The results were the usual hiccups :(. But after I used avisynth to do the joining also, the problem was gone. So I tried to just join them with that and leave out all the additional scripting. Guess what, it still worked. So the problem was with virtualdub all along :P. Thank you again IanB, without you, I'd probably be still pulling my hair out. And I'm pretty sure the cleanedge function will come in handy in the future :)

[StainlessS]

If you have a clip that is already joined in VirtualDub, and disposed of the source clip,
you could save the wav file and load into a wav editor (I like the nero wave editor, but
the freeware Audacity is good). You can magnify problem areas and do a fade in/out
or even mute. Audacity also has an option to fix an area "FreeHand" with pen type
editing. Then replace audio by using the "Audio from other file" option in VirtualDub.