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Allen Rowand

Anyone done LTC on a GoPro Hero 7 ?

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Has anyone successfully run LTC into a GoPro Hero 7? It works with no issues on a Hero 3, but I can't get usable LTC to timecode on the 7. I've tried with Davinci Resolve as well as the demo of LTConvert. If I record raw audio on the Hero 7 LTConvert finds the correct timecode in the audio file, but not in the video file.

 

I know about the Syncbac Pro, but I don't want to buy one because:

  1. I already have a couple UltraSync Ones.
  2. I don't need to shoot with a GoPro enough to warrant the expense.
  3. The Syncbac for the H7 only works with the H7; there's some issue why it won't work with the H8 and who knows if that will be resolved.

 

It's not a huge deal, GoPro footage isn't really a thing for me. I was going to drop it on stage as a third shot for a job that didn't happen, and now I'm trying to spend some time prepping for when it gets rescheduled… someday.

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On 3/19/2020 at 5:38 PM, Allen Rowand said:

LTConvert finds the correct timecode in the audio file, but not in the video file.

 

Hi Allen,
If you like, I'll have a look at one of the files to see what's wrong.
But, first see for yourself. Open the clip in any editor you might have, and look at the waveform.
(I bet it's a mess, or my work would have found 'something'.)

Bouke

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Do you only need the LTC to put TC for the video or do you need audio to go with the Hero7 video as well?

 

My first thought is that it’s your audio processing setting that is causing confusion. 


Check what it is set to. 
 

Low: Applies minimal processing to the audio file. Saves a .wav file with 3 separate audio tracks – one for each mic on the camera.

Medium: Applies some processing, including your manual audio choice if enabled (stereo or wind).

High: Fully processed audio (matches the audio that you’ll find attached with your video – but higher quality).

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1 hour ago, Display Name said:

Do you only need the LTC to put TC for the video or do you need audio to go with the Hero7 video as well?

 

My first thought is that it’s your audio processing setting that is causing confusion. 


Check what it is set to. 
 

Low: Applies minimal processing to the audio file. Saves a .wav file with 3 separate audio tracks – one for each mic on the camera.

Medium: Applies some processing, including your manual audio choice if enabled (stereo or wind).

High: Fully processed audio (matches the audio that you’ll find attached with your video – but higher quality).

 

LTC only, I've tried every processing level with mode set to stereo.

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For the records:
Current LTCconvert (version 6.0.6)  does read 'problematic' files, but I've got just one (newer) GoPro clip.
(It worked on other Hero files.)
In this version I've build in a low pass filter that 'should' take care of most glitches in the LTC stream caused by the smart processing. (Not good for normal sound of course, as it filters < 3K.
LTCconvert currently DOES NOT look at the sidecar Wave files, but I could alter that if it turns out that the lowpass filter still isn't good enough for rock 'n roll.

 

I would like to see an 'original' sidecar Wave file from a GoPro, that is NOT opened in LTCconvert. (As it's not a BWF, opening in LTCconvert will try to promote it to BWF, and that might fail / do some unwanted things due to some (at least at this time) incomprehensible metadata / chunk in the Wave.)


 

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hi Allen,
Does 6.0.6 also does not work on the clip you've send me?
(That would be very strange.)

 

 

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Hmm, 6.0.6 did work for me...
However, I've altered the routine again, and it now works (at least here) on both files.

The 25 FPS you see is from your settings. The column dispays the source FPS, NOT the LTC FPS.

(After scanning, you can see the LTC FPS when double clicking a clip.)

 

6.0.7 is now on my site, but even if it does work for you now, I would not do production this way.
Your second testclip is strange. The signal is a reversed sawtooth. That normally indicates a wiring, impedance or hardware problem.

Or, the cams electronics kicked in. The Wave is starting OK, fading out quite fast, fade in with the sawtooth. That looks like the cam detected a 'problem' and tried to fix it....

 

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6.0.7 still isn't working for me on any of my clips. My main machine is a Hackintosh but I get the same result on my MacBook Air.

 

It definitely seems like the Hero 7 is doing some sort of jiggery-pokery with the audio in the video file that can't be defeated.

 

This isn't critical; I was scheduled (and will hopefully be rescheduled) to do a two camera shoot and wanted to drop a GoPro onstage just to have another angle. If the client wants a third angle they can pay enough for me to warrant getting another camera or a SyncBac Pro, or I can shoot with my Hero 3.

 

I appreciate you trying to get this to work. I'd be happy to continue if you'd find it helpful for your software, or to say "enough" and just not use the Hero 7.

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Well, it also makes a nice real world testcase. (Ok, a nightmare one, but still fun.)
What I don't get is why it works here and not  on your systems.

 

Do both the Wave files work as expected? (The first one is a bit soft, but readable, the second one took me some time to adjust the code.)

 

Worst case, I can always fall back to the Wave files, but I need to write some extra code to make that happen.

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I'd be happy to retest and send any logs you'd find helpful. I can also create a new test clip so that we know the expected TC value and have good levels.

 

One wav file works as expected, the other wav and both video files fail. Getting the levels optimized id difficult, since neither device offers real level control.

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Please send me more testfiles! (15 seconds is plenty.)
And, please tell me what (audio) settings were used!

 

15 hours ago, Allen Rowand said:

since neither device offers real level control.

Well, normal TC output is quite loud, I take it you select 'line' input on the gopro?
Then, I'm not quite sure if ProTune will affect external input...

 

please use my WeTransfer:
https://videotoolshed.wetransfer.com/

 

I'm pretty sure there will be 'some' magical settings, and using the .wav instead of the AAC sound is not that hard, so I'm pretty sure I can make this fly.

If you have a clap,  please use it and also send your normal corresponding BWF files.

 

 

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