# Audio in Computer Video -\> Mono to Stereo **URL:** \ **Category:** Factual Questions\ **Created:** [January 12, 2005, 3:59am UTC](https://boards.straightdope.com/t/audio-in-computer-video-mono-to-stereo/284331 "2005-01-12T03:59:34Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![caphis](https://avatars.discourse-cdn.com/v4/letter/c/e19adc/32.png) [@caphis](https://boards.straightdope.com/u/caphis)\ **Post date:** [January 12, 2005, 3:59am UTC](https://boards.straightdope.com/t/audio-in-computer-video-mono-to-stereo/284331/1 "2005-01-12T03:59:34Z")
Ok, so, I’m transferring some home videos on VHS to DVD. The way I’ve been doing this is running my VCR’s RCA outputs into my DV cam, then out in DV-AVI format to my computer via firewire. This works fine, except my VCR only has one audio output, and as such, my DV cam interprets this to mean that there’s only audio in one channel. What software is available to tell my computer “take the audio from the Left channel and put it in the Right channel also, since the Right channel is empty”? ---
**Author:** ![The\_Cat](https://avatars.discourse-cdn.com/v4/letter/t/b9bd4f/32.png) [@The\_Cat](https://boards.straightdope.com/u/The_Cat)\ **Post date:** [January 12, 2005, 4:36am UTC](https://boards.straightdope.com/t/audio-in-computer-video-mono-to-stereo/284331/2 "2005-01-12T04:36:20Z")
Instead of software i would buy a Y adapter at radioshack that would split the mono signal into to channels before it enters your Cam. I know they make Y adapters that will take a stereo input and turn it into a mono, I’d imagine they make an adapter that would do the opposite. ---
**Author:** ![caphis](https://avatars.discourse-cdn.com/v4/letter/c/e19adc/32.png) [@caphis](https://boards.straightdope.com/u/caphis)\ **Post date:** [January 12, 2005, 4:48am UTC](https://boards.straightdope.com/t/audio-in-computer-video-mono-to-stereo/284331/3 "2005-01-12T04:48:11Z")
> [@The Cat](#): > > Instead of software i would buy a Y adapter at radioshack that would split the mono signal into to channels before it enters your Cam. I know they make Y adapters that will take a stereo input and turn it into a mono, I’d imagine they make an adapter that would do the opposite. Hmm, I could… the problem is that I’d already converted hours of footage before I watched it back and noticed what had happened. Anyone have any other ideas? ---
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [January 12, 2005, 6:19am UTC](https://boards.straightdope.com/t/audio-in-computer-video-mono-to-stereo/284331/4 "2005-01-12T06:19:09Z")
If you’re editing the video with the sound in Premiere or whatever, or you’re editing the soundtrack separately, is there an option to process the sound to fill both channels? :: looks around [http://www.videohelp.com/](http://www.videohelp.com/) for tools :: :: finds [listings of tools](http://www.videohelp.com/tools) :: I’m looking for a simple (perhaps command-line) utility program that will process a video or audio file to change mono sound to stereo in DV-format AVIs. VirtualDub ([free download](http://www.virtualdub.org/) of moderate size, 675 kB) appears to do this, but it looks like some experimenting is in order. ---
**Author:** ![aeropl](https://avatars.discourse-cdn.com/v4/letter/a/f05b48/32.png) [@aeropl](https://boards.straightdope.com/u/aeropl)\ **Post date:** [January 12, 2005, 6:42am UTC](https://boards.straightdope.com/t/audio-in-computer-video-mono-to-stereo/284331/5 "2005-01-12T06:42:34Z")
I had the same problem and I ended up buying the Y adapter at radioshack. It works well and without the hassle. Good luck. ---
**Author:** ![Rex\_Fenestrarum](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rex_fenestrarum/32/7265_2.png) [@Rex\_Fenestrarum](https://boards.straightdope.com/u/Rex_Fenestrarum)\ **Post date:** [January 12, 2005, 7:54am UTC](https://boards.straightdope.com/t/audio-in-computer-video-mono-to-stereo/284331/6 "2005-01-12T07:54:50Z")
Yes, the Y-adapter is really the way to go here. I’m going to assume that you’re creating content in the MPEG-2 format, as that is the native DVD format. MPEG streams are basically a video stream with a separate audio stream. There are freeware tools out there (TMPGEnc and probably VirtualDub) than can “demux” your video into a video part and an audio part (as a WAV file). You can then use a WAV editor (I like Adobe Audition) to upsample the audio to “stereo” and then reencode the video using a freeware tool like VirtualDub. The downside to all of this is that there’s a learning curve involved and it will take _hours_ to do this, even with a fast PC. I’m guessing that 1 hour of video will take 5 or 6 hours to convert, assuming that you have around a 1GHz PC. So your easiest and fastest option might be to either buy a y-adapter and start over, or buy a stereo VCR and start over. ---
**Author:** ![caphis](https://avatars.discourse-cdn.com/v4/letter/c/e19adc/32.png) [@caphis](https://boards.straightdope.com/u/caphis)\ **Post date:** [January 12, 2005, 7:56am UTC](https://boards.straightdope.com/t/audio-in-computer-video-mono-to-stereo/284331/7 "2005-01-12T07:56:18Z")
Tried VirtualDub, just couldn’t get the hang of it. I ran to WalMart and got a Y adapter for $2. Seems to be doing the trick just fine! Now to the tedious part… I can’t seem to use the DV cam as a simple pass-thru, so I have to go from VCR-\>DV tape, then DV tape-\>computer. :-/ Ah well, I only have about 2 hours of footage, so 4 hours should do. ---
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [January 12, 2005, 3:26pm UTC](https://boards.straightdope.com/t/audio-in-computer-video-mono-to-stereo/284331/8 "2005-01-12T15:26:33Z")
> [@caphis](#): > > …I can’t seem to use the DV cam as a simple pass-thru… This function is often extremely non-obvious. I had to read the manual three times before figuring out how to get mine to do it. It was some weird combination of operating mode and plugging in a cable–I don’t quite remember now. ---
**Author:** ![caphis](https://avatars.discourse-cdn.com/v4/letter/c/e19adc/32.png) [@caphis](https://boards.straightdope.com/u/caphis)\ **Post date:** [January 12, 2005, 7:58pm UTC](https://boards.straightdope.com/t/audio-in-computer-video-mono-to-stereo/284331/9 "2005-01-12T19:58:23Z")
> [@Sunspace](#): > > This function is often extremely non-obvious. I had to read the manual three times before figuring out how to get mine to do it. It was some weird combination of operating mode and plugging in a cable–I don’t quite remember now. Hmm… I already re-converted the footage (in 4h, 10 mn), but I’ll read the manual oncemore before I do it again. I thought I’d looked through it with a fine-tooth comb, but the way mine’s set up, you run VCR RCA outputs through a special cord into a mini-jack that goes into the DV Cam. To record from VHS, the DV cam needs to be in “Play” mode, then you press record once you start the VCR. Once that’s done, you hook the DV cam up to the firewire and in video software on the computer, “Begin Capture.” Now, without capturing, I could work it as a pass-thru-- on the computer monitor, I got live video from the VCR. When I pressed “begin capture,” though, it made the DV cam’s cassette begin playback. My first idea was to just take the tape out, but I didn’t try it.