GoPro Footage popping between clips (or on clip transition)

Robert-Kinney wrote on 12/12/2021, 11:03 PM

When editing GoPro footage, every single transition from clip to clip (regardless where I end the previous or start the proceeding clip) there is loud popping (or series of loud popping). It makes the film completely unusable.

To get around this in the past, I have separated the audio track from the video, extended the audio part on both sides to go beyond the start and end of the clip, then fade in and out the audio. This is fine if you only have a few GoPro clips in the movie. However, I have started using the GoPro extensively and my latest film is a complete popping mess - it's unusable.

Yes, the Go Pro footage is free of any popping anywhere when I listen to it on Windows 10's movie viewer.

The GoPro footage pops no matter where I start or end the footage.

The Magix preview window has the exact same popping issue as the fully rendered video.

My DSLR footage, phone footage, or any other camera I use never have this problem when I edit them in Magix - it's only the GoPro footage.

I have had this problem for at least three years with two totally separate computers using 3 different GoPro models using all the different Magix versions over the years. I keep thinking it will go away with the updates. So tonight, once again, I purchased the latest and greatest Magix Movie Edit Pro Premium (now running version 21.0.1.107) and... it still has the popping issue.

Help - I really need this fixed as it's delaying films I need released in the next few days.

Thank you for your time and assistance!

Comments

CubeAce wrote on 12/13/2021, 1:06 AM

@Robert-Kinney

Hi Robert and welcome to the user to user forums.

There are a lot of reasons for edited clips to pop and difficult to pinpoint what may be the reason without the tools to measure which it isn't the cause. The easiest and quickest way would be to supply two short video clips via a link to the forum here in this topic thread for a few of us to test. The files must come from a file sharing site such as DropBox or Google drive and not a video sharing site where the file will be re-compressed or re-encoded.

Three reasons I can think of straight away as to why this is happening is.

DC offset of the audio waveform. There can be a few reason for this to happen.

The editor cannot read the wave file correctly and find the zero crossover point of the audio to make the edit.

The file is variable frame rate and the edit point of the video section of the file cannot match the audio point of the edit.

Ray.

Robert-Kinney wrote on 12/14/2021, 1:10 PM

Hi, Ray! Thank you for your reply. I am learning this area and your feedback was enlightening.

I have uploaded a couple raw samples here, plus one that I put together and rendered in Magix. I am very curious as to an assessment of what my core issue is so I can make adjustments on how I record or any configurations or techniques to use in post.

Thanks again for your time!

Rob K.

CubeAce wrote on 12/14/2021, 3:24 PM

@Robert-Kinney

Hi Kenny.

Are you using an external mic? If so does it run on a battery?

Ray.

Robert-Kinney wrote on 12/14/2021, 3:53 PM

Hi CubeAce - yes, I am using a RODE VideoMicro (no battery) running through the GoPro USB-C to analog adaptor. My GoPro is a 7 Black series. Hope that helps.
Rob

CubeAce wrote on 12/14/2021, 4:08 PM

@Robert-Kinney

Hi Robert

I ask because the waveform does not rest at 0 volts. If it is an external mic try recording with the internal mic and see if you still get the pops.

I can reproduce this happening in Movie Edit Pro. So I needed to open the file in another application and see if the same thing happens

So when I opened the audio in Cubase, any starting or stopping of playing the file resulted in a pop being generated.

Upon closer inspection of the waveform it mainly sits above the 0 volt line and when silent drops to the negative rail.

On playback where there is volume it looks like this until it goes silent.

Compare that to a file that is recorded where the volume at rest is at the 0 voltage point.

And at volume.

I think what is happening is whenever a file is started or stopped or edited that the voice coil of whatever you are using is suddenly thrown forwards (or backwards depending on polarity.) and this is what is causing the pops.

I tried to remove the DC offset but it just made it worse. We are looking at the wave-forms at the millisecond level.

I'm not sure what to do to cure this if the cause is not a powered mic or going through an external preamp.

If anyone else can download the files and either verify it pops on their system or can look at the waveforms in their editing packages for conformation I would be grateful.

Although if played in Windows Flim and TV or Windows Media Player nothing can be heard, the file GHO13658.MP4 if opened with VLC player and started or stopped before the first second is up (you may have to manually place the playback marker back to the start manually) You should hear a very low frequency bump sound where a voice coil is quickly changing position from rest. On my studio monitors I am hearing that very clearly.

Ray.

CubeAce wrote on 12/14/2021, 4:12 PM

@Robert-Kinney

Hi Robert.

I have just finished putting the last reply together and missed your reply.

I can't use Rhode video mics with my Osmo Pocket. They just don't work well with any of the DJI cameras, so it could be that.

Try a recording not using an external mic and see if the pops go away. If they do I suggest getting another mic from another company. Funnily enough they work with my DSLR.

Ray.

CubeAce wrote on 12/14/2021, 4:18 PM

@Robert-Kinney

Hi Robert.

As an aside. My son also tried the Rhode Video micro and could not get that to work well either on his Osmo Pocket or Go-Pro Hero 4.

He uses the same make of mics I now do but buys his ready made whereas I buy the capsules and make my own. I'll see if I can find the site.

{Edit} Got it. Here.

Ray.

johnebaker wrote on 12/14/2021, 5:00 PM

@Robert-Kinney

Check if there is a firmware update for your Go Pro 7 - a quick Google search resulted in my finding reports of a DC Offset issue, as @CubeAce has shown, with several models of GoPro.

Are there any settings in the GoPro for 'muting the mic' when the audio level falls below a set threshold?

John EB
Forum Moderator

Robert-Kinney wrote on 12/14/2021, 5:13 PM

Thank you, CubeAce, for the extensive analysis - I'm quite impressed! I did look through that site and am wondering which one is the equivalent of the mini shotgun mic that I can use.

Just so everyone knows how I deal with the issue, here is my sample project in the editor (see attached/below). I unlink the audio on every single clip, then fade it out and back in. So on the sample I provided of a rendered video, this is now fixed on my computer.

As you can guess, this gets really cumbersome when I have 100 or more clips in a video. It's also a pain to edit anything after I have done all these fades.

Robert-Kinney wrote on 12/14/2021, 5:14 PM

@Robert-Kinney

Hi

Check if there is a firmware update for your Go Pro 7 - a quick Google search resulted in my finding reports of a DC Offset issue, as @CubeAce has shown, with several models of GoPro.

Are there any settings in the GoPro for 'muting the mic' when the audio level falls below a set threshold?

John EB
Forum Moderator

Hi, John! I will check for these firmware updates and let you know if it's been repaired. Thank you!

CubeAce wrote on 12/14/2021, 5:44 PM

@Robert-Kinney

Hi Robert.

Unfortunately if you want a shotgun mic from that site it will be a do it yourself job. They have great capsules at great prices that cover a whole range of needs but they don't build much themselves. My son uses the one I show as a lavaliere.. I built a wide angle stereo mic using an old LED torch for the body.

If it turns out to be a firmware problem as John suggests then happy days. The mic may well end up being usable. It just doesn't produce enough volume for the DJI cameras. If it still presents problems volume wise Saramonic do a nice range of microphones slightly cheaper than Rhode for an equivalent mic.

That was a good catch by @johnebaker as I wasn't aware of any problems. I suspect nor does my son so I'll let him know.

Thanks John.

There is however a problem with using audio files with a DC offset. That is the rest position of a cone is not 0v and that means during play the rest position will be sending a constant current to your speakers or headphones pulling th rest position out of true and holding it an amount back or forward when static and in motion. (Hence the term DC Offset) That is like running an electric heater and at loud volumes could, and has in the past, overheated voice coils and burned them out during long sessions of playing.

Normally this can be cured by an audio editor that has the ability to correct the problem but it just made those clips worse. This is the first time I've not been able to reset a DC offset problem. I do hope there is a firmware solution for you.

Ray.

Robert-Kinney wrote on 12/14/2021, 6:01 PM

Hi Ray - thank you for the information. I'll look closer at the Saramonic mics - I've browsed them for a few minutes looking at possibilities.

As an update for the firmware:

Updated GoPro to latest firmware. Tried external RODE microphone. Created sample movie. Same result - still popping between clips.

Completely unplugged microphone and the USB-C analog converter and used onboard GoPro mic. Same result - still popping between clips. 😡

Have we isolated this to a GoPro problem? This isn't the first time I've had issues with a couple other GoPros. The older GoPro I used to use had similar problems and it was using the onboard mic.

I find your comments very informative - much appreciated.

CubeAce wrote on 12/14/2021, 6:06 PM

@Robert-Kinney

Hi Robert.

I have never used a Go-Pro personally but I know the DJI products sometimes have audio board failures and have to be replaced. Thankfully most play up before the warranty period is up, so yes if the Go-Pro is doing the same with the inboard mics there is a problem.

Sorry.

Ray.

johnebaker wrote on 12/15/2021, 2:23 AM

@Robert-Kinney

. . . . Completely unplugged microphone and the USB-C analog converter and used onboard GoPro mic. Same result - still popping between clips. 😡

Have we isolated this to a GoPro problem? This isn't the first time I've had issues with a couple other GoPros. The older GoPro I used to use had similar problems and it was using the onboard mic. . . . .

It looks very much like the GoPro is the issue.

Personally I do not use a GoPro, however I have some GoPro clips from another member of the forum and they do not click/pop in MEP. Also a Youtuber I follow has had issues with audio from his Hero 7 with a Rode Wireless GO microphone.

John EB

Robert-Kinney wrote on 12/15/2021, 9:14 AM

Hi, John - I think I agree - it has to be a GoPro issue. I downloaded Adobe Premiere last night and tried making a video. The results: SAME THING! I don't think I'm gaining anything switching platforms at this time. I was pretty clumsy in Premiere and I think Magix is a bit faster at roughing in video because of the way the slicing tool works and the play bar.

However, there is a workaround in Premiere . Basically, in this one minute tutorial, the creator (in what he calls) a two-frame [audio] transition and pasting it on every cut. This actually worked when I tried it with my footage in Premiere. John and CubeAce, do you know of how to do something similar to this in Magix?

Thanks again for both of your help - it is much appreciated!

johnebaker wrote on 12/15/2021, 12:02 PM

@Robert-Kinney

The workaround demonstrated in the video above is masking the pops caused by the DC-offset.

There is an alternative in Movie Edit Pro to automatically remove a set number of frames from the start and end of the video clips - by adjusting these settings you can remove the clicks from the sudden drop in the audio level on import - see the Program settings, Video/Audio tab as shown below

Once you have the correct settings editing should be easier.

HTH

John EB

Robert-Kinney wrote on 12/15/2021, 1:13 PM

Thanks, John. Your help is much appreciated. You both have helped me understand where the root cause is and given me much needed direction. My plan will be to purchase a new camera and sell this old one. I need something I can edit fast and this camera is not on my list for the recipe of success.

Now just to figure out why Magix is completely hard-locking since I upgraded. This will be a new post...

Thanks again!