out of phase audio track channels

[thibaultphil]

Hello,
on the audio track of a show, the signals of the 2 channels of the music (wav audio file) are not in phase with the music which makes it impossible to set up sequences set to the music (for example a flash on a bass drum hit)
the test was carried out on pc windows 11
Intel(R) Core(TM) i5-8250U CPU @ 1.60GHz 1.80 GHz, 8.00 GB
qlc v4.12.5

any file can be put in the audio track

Thank you for your intervention

[thibaultphil]

a test carried out on the same PC with version 12.4.3 works very well. What regression has there been between these 2 versions.
Thanks

[kenact]

I just tested it on Windows 10 x64 and 4.12.6. I imported a WAV file, and everything is perfectly in phase.

I'm on a Dell M6700 laptop with 32gb RAM.

[kenact]

Something I did find, if you add an audio track, Preview in my case Mono, then replace the audio file with a longer audio file, the displayed wave expands to the length of the new file, but the wave image remains the same. Removing the preview and putting it back on, restore the wave to what it should be.

Conversely, if you replace a longer audio file with a shorter one, the wave image shrinks to the size of the smaller one. Again, remove the preview, then restore it, the wave image shows up properly.

[thibaultphil]

Thank you for your participation in the forum and for your response. unfortunately your solution does not work on my pc in version qlc 4.12.5.

[kenact]

I just tried it on 4.12.5, with a stereo track that's 2m31s634ms, and it maintained synch throughout the track.

Are you using a longer or shorter track? What are you using for your audio output device?

[edogawa]

I also tried this morning, in windows, and while I don't see a waveform anywhere in QLC+, whatever file I load, it just plays correctly.

[kenact]

I also tried this morning, in windows, and while I don't see a waveform anywhere in QLC+, whatever file I load, it just plays correctly.

Right click the audio track and choose any of the Preview items.

[edogawa]

Thanks Ken, I don't use shows much, now I remember I've seen/used wave previews before...

Anyway I see the same happening - after changing the audio file, the waveform display stays the old one but gets stretched/shrinked to the new duration, until I switch off and back on its display (or switch to a different of the three options L,R or stereo display). Once that's done, what I see on screen aligns perfectly with what I hear.

[edogawa]

I think I found an easy fix for the display issue (call the preview thread calculating the pixmap when a new audio file gets loaded) and have prepared a pull request.

https://github.com/mcallegari/qlcplus/pull/1376

Now I'd like to know if this was the OP's actual problem, or did he really mean audible phase/sync issues, which I cannot reproduce in 4.12.6 Win10, nor with current Git under Linux...

[thibaultphil]

hello,

I'm sorry but this link is not available: viewtopic.php?f=22&t=15924.
The correct display of waves in show mode (version 4.12.3) is random. It is also random in VC mode when the show is in a cuelist. When reading, the light effects that should have been set to the music are shifted.
tried all the proposals: integrate a video, put a longer audio, convert to wav with audacity.
Thank you for your investments

[edogawa]

I'm sorry but this link is not available: viewtopic.php?f=22&t=15924.

Yes, I made a mistake in markup, thanks... I edited and fixed that link in the github comment. Anyways, it only points back to this thread.

I can`t seem to reproduce the problem you try to describe, on any of my QLC+ installations, in Linux or Windows. I'm using 4.12.6 and current git though, as mentioned above.

I won't go back and install 4.12.3 or .5, though, rather I am curious why you don't update to .6?

The issue described by kenact (wrong wave image stretched-to length of newly loaded audio) seems solved by the change in my pull request on github, which still is being discussed.

[thibaultphil]

I used version 4.12.6, I encountered the same problem. This discrepancy occurs on music lasting 8 minutes. is that a reason?

[kenact]

I used version 4.12.6, I encountered the same problem. This discrepancy occurs on music lasting 8 minutes. is that a reason?

In your test, does it occur at the beginning, the end, all the way through?

Are you using a WAV, MP3, AIFF, other type file?

[thibaultphil]

J'utilise un fichier enregistré en format wav par audacity. Cela se produit dès le début de la lecture, la barre de lecture commence à défiler, le son n'apparait qu'après un demi seconde.

[edogawa]

This is an english forum, please be so nice, take an extra minute and use an online translator, but don't post in french...

here's the englsh translation:

I use a file saved in wav format by audacity. This happens as soon as the playback begins, the playbar begins to scroll, the sound appears only after half a second.

So it's an audible delay in relation to where the show manager's playhead points. I cannot reproduce that in Win10 nor Linux, and it's completely unrelated to the issue the code change described above tries to address.

[Deece]

Hi, check the audio file. I have found that Audacity sometimes adds half a second of silence at the beginning of the the track.

(Bonjour, vérifiez le fichier audio. J'ai constaté qu'Audacity ajoutait parfois une demi-seconde de silence au début de la piste.)

[kenact]

Hi, check the audio file. I have found that Audacity sometimes adds half a second of silence at the beginning of the track.

That shouldn't put the wave image out of sync with the audio.

[kenact]

I just create a 9 minute WAV file with a distinctive beat, that is easily seen in the wave image. The music stayed in sync with the wave image for the entire 9 minutes.

Can you give any more details that might help reproduce the issue you're seeing?

[thibaultphil]

I provide you with my reduced project, the reduced music and the video. In show mode the 1st cymbal hit arrives at 18"9 according to the waves. On reading it can be well set or arrive at 20". if you pause and start playing again it stops correctly again. In VC mode it is systematically shifted in relation to the lighting.
Thank you again for your help. I've been using QLC for a long time and wouldn't want to part with it.