irritating "heartbeat" clicking in rendered video.

[Glen_S]

I have noticed this in a couple of videos I've done now, I put together some aerial footage I have done, and after I render it there is a low click-thump sound, almost like a slow heart beat. This is not in an added audio track, and it does not do this in the preview.

I am uploading a clip to youtube as I write this, (will update when done) where I left the native audio in place the whole time (rather than add a music track) so it can be heard.

Any idea's what's causing this? The raw files are MP4 files from a GoPro HD Hero camera.

thanks..

ps. in this video, you can hear the sound I am talking about, but only until I fade it out and start the music track

[Black Lab]

It's funny you describe it as a hearbeat. It was described the same way in this thread.

[Glen_S]

The video is finally updated, you can watch it here

[teknisyan]

Cool video!

Thanks for sharing!

[Ken Berry]

After looking at the video, I am wondering whether you had the camera attached directly to your head... and thus the heartbeat could indeed be just that, or at least your pulse which the camera is picking up from direct contact with your skull...? Just a thought...

[Ron P.]

After looking at the video, I am wondering whether you had the camera attached directly to your head... and thus the heartbeat could indeed be just that, or at least your pulse which the camera is picking up from direct contact with your skull...? Just a thought...

Don't think so Ken, he's flying an RCA (Radio Control Airplane). The video in his first post shows him as he's trying to land the plane.

[Ken Berry]

Only saw the one flying around and assumed it was an 'ultra light'...

[Clevo]

Only noticed the heartbeat while in the air while the engine is running so I think it might have something to do with the electro magnetic interference generated by the engine and picked up by the mic.

Similar to how you can video screen flicker on a tv Screen due to no sync of the cycle rates...

you have a confulence of sound waves happening

[Clevo]

As for a solution what I would do is send the plane up and do a glide like you did on your "dead stick" landing approach and record as much sound as you can with no engine noise... if you can grab between 30-60seconds of natural sound you then have your own Sound FX.

Next time you edit a video of a flight... mute the noisy video and add your sweet wind noise....

perhaps another suggestion is to try switching sound normalisation off (or on if you already have it off) when creating a video file and see if it makes a difference.

The heartbeat is being introduced during rendering by the sounds of it... so the other option is to split the sound away from the video and create a .wave sound track and use that.

[Glen_S]

I thought maybe too it was a resonance thing, but it's totally absent during the preview. It also doesn't show up when I use Vegas Pro.

Splitting off the audio and converting to wav is a good idea, I had to do that with the first video link, when the music track was mp3 I was getting clicks and pops, changing it to wav fixed it.

You're right Ron, RCA - built specifically for AP & AV - I need lots more practice though! It'll carry a DSLR, but I'm happy with a GoPro for now, also have a zi8 and flip mino hd to put on it, I can carry all three of those at once if I want.

[Ron P.]

Wow... I'd love to be able to get a setup like that. You ever get nervous about crashing? I mean it is possible to not only trash a good RCA, but the camera too...

[Glen_S]

Wow... I'd love to be able to get a setup like that. You ever get nervous about crashing? I mean it is possible to not only trash a good RCA, but the camera too...

Well, this time last year I had not even flown an RC plane at all, then for fathers day I bought my self a cheap RTF (ready to fly) Super Cub for $180, flew that a couple of times, then got the idea to put one of those cheap $10 ebay cams on it, did my first aerial video and was thrilled with it, and I was hooked. Then I got the idea I wanted to do some serious AP and AV, so did some research and asked a lot of questions on some AP boards, and decided to build my own plane from plans that a guy that has his own AP/AV business and designs his own aircraft.

So, to answer your question, when I took off the first time with this home built plane, with my $300 gopro held on the front with some elastic bands, when I probably had only 10 flights in total since I took up the hobby - nervous does not even begin to describe it!

On my 2nd flight with this bird, the wind came up and I lost orientation (easy to do) I finally just cut the throttle when the plane disappeared in the dusk, and started walking across the ice (I was on a frozen lake) in the direction I last saw it. Imagine how I was feeling after walking, walking and walking some more and still no plane, (which I'm into for about a G-mark including the camera) - I ended up almost 3 km's away when I found it sitting on the ice, intact.

Since then I have put on a live downlink (many more $$$ and you can see my ground station in the video) so I can see what is happening from the planes point of view and help me frame my videos & photos better.

You can see some video of the plane from the ground here, I did some overlay with my aerial video to show both.