Author Topic: Poor Audio Cuts?  (Read 2495 times)

eumagga0x2a

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Re: Poor Audio Cuts?
« Reply #15 on: November 17, 2018, 01:08:52 PM »
Thank you for identifying the cause of the problems with the antispam service, I guess it should be pinned as README somewhere.

Did you re-encode audio for that click/blip/whatever at the start of a video as in https://youtu.be/2sHpk28Q7oY? Was the audio track internal or external?

If you copied audio, then the whole theory about already decoded audio somewhere in a buffer does't apply.

Of course, H.264 via x264 is by far superior to older mpeg4 codecs like DivX. Only if the target equipment is not capable of decoding H.264 (like an ancient DVD player) or your PC is so slow that encoding with x264 would take an eternity and the graphics card is not NVIDIA or too old to allow to use NVENC, resorting to H.263/DivX/Xvid were justified. Choosing H.265 (HEVC) instead of H.264 should be well thought out, however. Both encoding and decoding demands a very powerful CPU or working hardware acceleration for HEVC.

eumagga0x2a

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Re: Poor Audio Cuts?
« Reply #16 on: November 28, 2018, 04:38:16 PM »
The green flash on starting playback should be fixed now, please try a future nightly (r181129 or later).

Apart from that, a response to the questions in my previous post would be appreciated.

BatmanLoko10

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Re: Poor Audio Cuts?
« Reply #17 on: May 10, 2019, 03:52:07 PM »
The green flash on starting playback should be fixed now, please try a future nightly (r181129 or later).

Apart from that, a response to the questions in my previous post would be appreciated.

Sorry, I'm horrible at remembering logins and due to that and not doing too much video encoding lately, I didn't update the thread.

Thank you for identifying the cause of the problems with the antispam service, I guess it should be pinned as README somewhere.

Did you re-encode audio for that click/blip/whatever at the start of a video as in https://youtu.be/2sHpk28Q7oY? Was the audio track internal or external?

If you copied audio, then the whole theory about already decoded audio somewhere in a buffer does't apply.

As I recall, it was an Internal track, and I reencoded the audio.
I am happy to report though, that I have tested the latest nightly, and can confirm that the green flash is fixed. Not only that, but it seems the audio blip is also completely gone! Thank you so much for your help with this. For reference, I made the same clip again, with Avidemux 2.6, 2.7.1 and 2.7.3:
https://youtu.be/ho7tJspnDwM
https://youtu.be/YioWEB0v5cg
https://youtu.be/DL2ZHIQGaPE

As you can hear, there's no blip in 2.6, there is a blip in 2.7.1, but there's no blip in 2.7.3. The issue appears to be fixed. I'm still not used to the B Marker working differently though!  :P

However, 2.7.3 seems to bring with it it's own issues. It seems that the latest version offers support for HiDPI Windows device but the implementation is problematic. When running in Windowed mode with a clip open, the bottom of the Avidemux program is cut off by the Taskbar, meaning you're unable to see timeframes. When running in full screen, Elements of the GUI begin to overlap, and the program is almost unusable. I have attached screenshots to demonstrate this. Should I create a new thread for this issue? This is on a 1920x1080 13.3" Laptop.


Also, can I ask what people would recommend are the best settings for short .mp4 clips like the ones I've been posting in this thread? I mentioned what I used initially, but you kindly pointed me towards using Mpeg4 AVC (x264) instead, as well as using the "MP4 Muxer" Output Format instead of "MP4v2" (The Muxer doesn't open if I use x264 with MP4v2, so I can't encode anything). Is AAC (lav) a fine audio encoder, or could I do better? Are the settings i'm using fine?
« Last Edit: May 10, 2019, 05:21:42 PM by BatmanLoko10 »

eumagga0x2a

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Re: Poor Audio Cuts?
« Reply #18 on: May 10, 2019, 05:45:09 PM »
Quote
When running in Windowed mode with a clip open, the bottom of the Avidemux program is cut off by the Taskbar, meaning you're unable to see timeframes.

Yes, I experience it too that in HiDPI conditions on Windows, it is necessary to manually resize the window for the correct zoom value to be applied.

Nothing was changed regarding that brief portion of previously decoded audio somewhere in a buffer.

There is no MP4v2 muxer in VC++ builds. If Avidemux shows it in the list, you must have installed it over a mingw-compiled build, which can't work.

For very short videos, reduce the GOP length in order to get at least 3-4 seek points within the video.


BatmanLoko10

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Re: Poor Audio Cuts?
« Reply #19 on: May 11, 2019, 04:32:30 PM »
Quote
When running in Windowed mode with a clip open, the bottom of the Avidemux program is cut off by the Taskbar, meaning you're unable to see timeframes.

Yes, I experience it too that in HiDPI conditions on Windows, it is necessary to manually resize the window for the correct zoom value to be applied.

Nothing was changed regarding that brief portion of previously decoded audio somewhere in a buffer.

There is no MP4v2 muxer in VC++ builds. If Avidemux shows it in the list, you must have installed it over a mingw-compiled build, which can't work.

For very short videos, reduce the GOP length in order to get at least 3-4 seek points within the video.

With the latest Avidemux, it seems I can't resize the window because as it showed in the screenshot, the taskbar then cuts off Avidemux and I can't make it smaller.
I seem to have slight work around, and that's using an external manifest file. It disables the HiDPI and makes Avidemux lose the sharpness in its GUI by making things blurrier, but it seems to work.

You're sure nothing was changed from 2.7.1 to 2.7.3 regarding the audio buffer? It seems strange that the issue is completely gone now! I'm happy with it though. Older versions of Avidemux (2.6) do seem to still have the much earlier mentioned issue of audio cutting off prematurely when compared to Premiere Pro. Would there be any way of fixing the audio in 2.6, I know it's outdated though.

I don't have the VC++ build, just the latest nightly, if MP4v2 has been removed, then I assume it isn't recommended to use regardless so it's no big miss. I'll just use MP4.
Thanks for the tip regarding the GOP length, really appreciate it. Do you think the rest of the chosen settings are fine too?
« Last Edit: May 11, 2019, 04:38:35 PM by BatmanLoko10 »

eumagga0x2a

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Re: Poor Audio Cuts?
« Reply #20 on: May 11, 2019, 04:43:58 PM »
With the latest Avidemux, it seems I can't resize the window because as it showed in the screenshot, the taskbar then cuts off Avidemux and I can't make it smaller.

Just grab the window border at another side, it need only a small nudge to trigger zoom recalculation.

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I seem to have slight work around, and that's using an external manifest file. It disables the HiDPI and makes Avidemux lose the sharpness in its GUI by making things blurrier

That sounds horrible for me :-)

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You're sure nothing was changed from 2.7.1 to 2.7.3 regarding the audio buffer?

Not knowingly.

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I don't have the VC++ build, just the latest nightly

There are official latest VC++ nightlies and official latest MinGW nighlies.

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Do you think the rest of the chosen settings are fine too?

I'm sorry, but that was a general recommendation. Additionally, I'm not an expert in finetuning of x264 parameters.

BatmanLoko10

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Re: Poor Audio Cuts?
« Reply #21 on: May 11, 2019, 05:29:44 PM »
Just grab the window border at another side, it need only a small nudge to trigger zoom recalculation.
The Window only goes so small however, it has a minimum size and unfortunately that size is too big to fit on my screen and the program ends up being cut off by the Windows taskbar. You can see this in the "windowed" Screenshot I uploaded, it doesn't get any smaller.

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Not knowingly.
That is strange then! As you can see in those clips, the issue is clearly gone, I even tried the 2.7.1 build of Avidemux on a different machine and got the same blip.

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There are official latest VC++ nightlies and official latest MinGW nighlies.
I'll have to look into the VC++ builds, truth be told I'm not really sure what they are or how they work, as I generally just grab the installer from the Avidemux home page

Quote
I'm sorry, but that was a general recommendation. Additionally, I'm not an expert in finetuning of x264 parameters.
That's fine, you've already helped me plenty and told me better settings than the ones I was using! I used to used Mpeg4 ASP just because I didn't know any better! Thanks again

BatmanLoko10

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Re: Poor Audio Cuts?
« Reply #22 on: May 15, 2019, 06:14:17 PM »
Just another quick update on this thread if it's not a bother.

The aforementioned settings of Mpeg4 AVC (x264), AAC (lav) and MP4 Muxer do not seem to be ideal settings for short clips. It seems when encoding things that are around 1 second long, the process fails and Avidemux throws the error "the file is saved but seems to be incomplete". The output file will also not play and be corrupted.
I'm not sure if this is an Avidemux bug or just a video editing thing, but I thought it'd be worth mentioning.  Y
ou told me Mpeg4 ASP (ff) was an outdated output format, is Mpeg4 ASP (xvid4) superior since x264 doesn't seem to work in this case? Sorry, I'm not too experienced with this and I'm just trying to find the best settings but don't know which video ouput formats are better or worse. You did tell me x265 was the best, but that would require too much power so I'm not opting to use that.

eumagga0x2a

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Re: Poor Audio Cuts?
« Reply #23 on: May 15, 2019, 07:06:39 PM »
I never thought of clips that short. In this exotic case, you could try setting the x264 profile to baseline to disable B-frames. Usually, the encoder analyses quite a lot of pictures before being able to output even a single compressed frame.

xvid4 is just another implemention of the same obsolete mpeg4 codec.

BatmanLoko10

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Re: Poor Audio Cuts?
« Reply #24 on: May 16, 2019, 02:39:34 AM »
I never thought of clips that short. In this exotic case, you could try setting the x264 profile to baseline to disable B-frames. Usually, the encoder analyses quite a lot of pictures before being able to output even a single compressed frame.

xvid4 is just another implemention of the same obsolete mpeg4 codec.

Thank you, I can confirm that changing the profile did work. There does seem to be a slight quality difference when using my own configuration and choosing baseline. It also encodes quicker than the default "advanced configuration" Any idea why that might be? Enabling baseline is the only setting I changed in there after unticking "Advanced configuration".

If I wanted to open Avidemux with these settings by default, would this still be the best guide?
https://www.avidemux.org/admWiki/doku.php?id=tutorial:presets#example_save_your_x264_options

It does seem strange that clips that are around 1 or 2 seconds long don't encode right under x264, I don't seem to recall having this issue before at all, but perhaps I just never used the settings. Xvid4 and ASP (ff) work better but as you say, they're outdated and as I mentioned earlier, seem to give me problems when running in other programs. Would you recommend any other encoders?

Finally, I wanted to correct something I was saying earlier. I mentioned that the behaviour of the "B" marker has changed going from Avidemux 2.6 to 2.7. This is incorrect, it is actually the behaviour of the "A" marker that has been adjusted. I think I mentioned what has changed, but I could make a video demonstrating it in case I haven't been clear. Was this an intentional adjustment?

Once again, thank you for the help. The work you do on these forums is fantastic and it's good to see the commitment to a brilliant little program.
« Last Edit: May 16, 2019, 02:59:56 AM by BatmanLoko10 »

BatmanLoko10

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Re: Poor Audio Cuts?
« Reply #25 on: May 17, 2019, 02:42:50 AM »
Oh, and something that's not really a big problem at all but I thought I'd ask, is there any way to stop Avidemux from resizing itself once you open media?

eumagga0x2a

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Re: Poor Audio Cuts?
« Reply #26 on: May 17, 2019, 05:53:59 AM »
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If I wanted to open Avidemux with these settings by default, would this still be the best guide?
https://www.avidemux.org/admWiki/doku.php?id=tutorial:presets#example_save_your_x264_options

It depends on what exactly you want to achieve. If you need to add an easy way to revert to particular encoder settings without using the x264 preset menu in the encoder configuration dialog and without affecting any other Avidemux configuration like output container, this is the way to go. If you are okay with other config being set as well, you can just set the current configuration as default (Ctrl+Alt+D or via the "Edit" menu).

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is there any way to stop Avidemux from resizing itself once you open media?

Only if the Avidemux window is maximized.

BatmanLoko10

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Re: Poor Audio Cuts?
« Reply #27 on: May 17, 2019, 02:40:59 PM »
Quote
If I wanted to open Avidemux with these settings by default, would this still be the best guide?
https://www.avidemux.org/admWiki/doku.php?id=tutorial:presets#example_save_your_x264_options

It depends on what exactly you want to achieve. If you need to add an easy way to revert to particular encoder settings without using the x264 preset menu in the encoder configuration dialog and without affecting any other Avidemux configuration like output container, this is the way to go. If you are okay with other config being set as well, you can just set the current configuration as default (Ctrl+Alt+D or via the "Edit" menu).

Quote
is there any way to stop Avidemux from resizing itself once you open media?

Only if the Avidemux window is maximized.

Thanks for the tip on setting the current config as default. I've no idea why I didn't look for that already in the settings, pretty silly of me.
As for Avidemux resizing, understandable. It just seems whenever I open something 1080p, with the default Zoom settings the Avidemux program gets cut off by the Windows taskbar. Changing the zoom setting fixes it though, but otherwise no dice. Again, not a huge issue, pressing the "4" key takes no time, just thought I'd ask.

I think I'll bounce back between 2.6 and 2.7 for now. Still too accustomed to the previous A marker behaviour to fully change. Thanks
« Last Edit: May 17, 2019, 02:43:13 PM by BatmanLoko10 »