Dear all, i am new to the forums and this is my first post.

I watched some instructionvids on KDEnLive an decided to give it a go, and this is how far i came:
https://www.youtube.com/watch?v=NbH5ekLo4_Q
https://www.youtube.com/watch?v=xvyT9dZL8xU

As you can see all worked out pretty well except for the audio and video not syncing after rendering (the sound is ~300 m.second behind).
Playing back my project(in the clip monitor) all is fine.
I have been using Version 0.9.10 Using KDE Development Platform 4.13.3 it is the one preinstalled in KX studio...

The audio i made with Ardour @44.1kHz and the videos i made with a sony fotocamera and with a logitech webcam.

How should i fix this, please?
Thanks

Hi Afolk,

think this wont be the issue you described, but: did you try to export audio in 48khz and aligned? Like 48khz is the "standard" for DVD and digital audio on film, think this is usually the safest choice.....

afolk, is your audio separate? That is, you have it on audio tracks? Or is it part of video? Was the audio taken from the video? If it's from video, is audio in sync in the source video clips?

Hi and thank you very much for the input!
Yes my audio is separate, i have it on one (stereo)audio track. In Ardour i bounced at 44.1kHz.
There is also audio on the videofiles but it is muted(because of poor quality)

If play back the videotakes(including its audio) in SMP the audio is in sync but if i watch(with unmuted sound) it in the Clip monitor(in KDEnLive) it is out of sync.

What do you mean by "aligned", please? I dragged the (separate)audiotrack back and forth until it aligned with the video (in the clip monitor).
So the shift in time seems to take place in the rendering process.
Thank you!

What audio file format are you using for exporting audio from you audio editor into Kdenlive? What format are you rendering to, in particular, which audio codec?

Alignment refers to manually aligning separate audio that was not synced to video to be roughly in sync. Do I understand correct that you manually aligned your audio to video? Please note that the audio thumbnails are often out of sync (to my own experience), so you rather need to align using your ears, not the thumbnails. Scrubbing also helps.

Side note about audio encoders: for instance, I have voice over audio at 48kHz that sound well without any artefacts. With MP3 encoding or AAC at 128kbits I get annoying voice artefacts. At first I thought I did something wrong during denoising in audacity when post-processing the audio track. Later noticed that with AAC 192kbit these artefacts are gone. The post-processed 48kHz WAV is just fine, no audible artefacts. Strange.

Hi,
and thanks again for the input!

-What audio file format are you using for exporting audio from you audio editor into Kdenlive?
I am not sure what you are asking, in Ardour i exported to 44.1kHz @ 16bit so that would be .wav

-What format are you rendering to, in particular, which audio codec?
In KDEmLive i rendered to .mp4 i kept all default settings, have no clue which audio codec. (i guessed the defaults are fine for a youtube clip...)

Yes, I manually aligned audio to video.
-Please note that the audio thumbnails are often out of sync.
Out of sync to what, please? Playing back a clip in the Clip monitor(in KDEnLive) the audio is out of sync with the video. Is that what you mean, is it a bug?

Are you saying i should sync my separate audio track to the (now muted)audio on the videofiles? No??
Thank you!

Okay, wav format, that's fine. Some audio formats are difficult to seek, such as mp3. For those, actual cut positions may be different to where you want them to be. But not an issue here.

.mp4 is a container: it may contain different types of video and audio encodings, albeit only in a limited variety. For instance, one combination is H.264 video encoding, AAC audio encoding. Can you please check with this?

Audio thumbnails out of sync means: the audio wave shown in a clip in the *timeline* does not match correctly the real audio. That is, if you try to locate the beginning of a particular sentence, a period of silence, the thumbnail audio curve may be offset.

Did you check your final rendered video to also be out of sync in audio on a different playback device? For instance, a smart TV set, a smartphone, etc. to ensure that the offset is not simply of problem of your video player. What I don't understand is that you mention out of sync for the clip monitor? Are you sure on the clip monitor or did you meant the *project* monitor instead?

Hi,
thanks!
Sorry for the confusion, yes: i meant the project monitor instead. (had not realised it switched from "clip" to "project")
I checked the encoding: it is MP4 H.264/AAC High Profile.

Is my video in or out of sync with audio if you play it back on your device?

I will try to explain again.
for mazurKaat i have these "source"files:
-one separate (stereo)audio track (44.1kHz @ 16bit .wav)
-two videofiles including (poor quality)audio

Playing back any of the "source"video clips(including its audio) in VLC or SMP the audio is IN sync with the video.
Playing back any of the "source"video clips in KDEnLive(with unmuted sound) the audio is OUT of sync with the video.

I wish to accomplish:
-cutting and pasting snippets from the two "source"videofiles and mute their audio (that worked out fine)
-alligning the audio from the separate audio track to that video (i probably did that wrong BUT all seems fine in the project monitor)
-rendering to a format that is working for Vimeo and Youtube (i would prefer a Free/Libre format if possible)

Givven the Audio wave shown in a clip in the *timeline* does not correctly match the real audio, what would you suggest to be the best workflow, please?
I mean how should i sync my separate audio track to the video?
Thank you very much!

I have to admit that I'm out of ideas. I'm working solely with Kdenlive 15, 15.13.0 (~15.12.1) at this time to be precise. I don't experience such desync in my projects.

I render to H.264/AAC with 192kbit as the audio bitrate. All source audio (voice over and post-processed video lip audio) is consistently 48kHz. In early projects I had problems mixing 44.1kHz and 48kHz material where MLT messed up the faster audio material for some reason. So I'm using only a single audio rate of 48kHz within a single project.

I'm using AAC at 192kbit not because my voice is audiophile but because I experienced a lot of bad artefacts when encoding to MP3 or AAC with less than 192kBit. Strange, but using higher bitrates solved the audio artefact problems. To make things worse, different playback devices produced different audible artefacts at 128kbit but not at 192kbit. And my post-processed source audio is fine, no audible post-processing artefacts (at least to me using a quality Behringer USB audio mixer with AKG studio headphone for control).

YouTube reencodes anyway, as Google exercises control over the formats and bitrates in which it distributes video. You'll need to do some dry runs anyway. I never touched Vimeo because they still can't get their proprietary video player **** working halfway on Android. Only my Samsung TV gets along with Vimeo. That, and their insane restrictions made me ditch them immediately and keeping with YouTube: paying for hosting FullHD content (1080p)? No way, thanks.

...okay, thank you anyway!
No succes yet

Any help is highly apreceated

kalimerox gave you a very good suggestion right at the start, which it appears you still haven't tried yet: exporting from Ardour at 48khz.
As a rule of thumb, when you're doing any video project, think 48kHz, 48kHz, 48kHz... this will avoid a lot of sync problems.
Your camera records audio at 48kHz, and when you export to from an NLE to MP4/m4a, even if you have 44.1kHZ audio involved, the result is also 48kHz.
Please bounce from Ardour at 48kHz and try again.

thanks! yes i will try that

https://www.youtube.com/watch?v=Z00UHAyey9U