Avidemux 2.6.4 - H.264 encode by video size is massively broken

[mean]

cannot reproduce

[thany]

On Windows XP you can't? I can, every single time. On different pc's.
What else do you need from me in order to reproduce it? I think I have given all the information I could find, apparantly you need more... All you have to do is ask!

[Robby]

Hello guys.

I'm certainly no expert on this so i'm afraid i have nothing to add in terms of potential solutions. I just logged in here for the first time in years to report the very same issue that Thane have. I went through the nice guide you guys have for x264 in your wiki and managed to get nice quality video for my purposes of around 22 MB per minute in Avidemux 2.6.1. I now tried upgrading to 2.6.5 and used the same profile and exact same settings everywhere and the processing of one minute of the same file ended up being 465 MB, using two-pass average bitrate.

Where the average bitrate value during the second pass showed around 30K during the most motion-intense parts in 2.6.1, it shows as 130K in 2.6.5. The image quality doesn't even seem better either.

Are there any logs i could send you to further help investigate this? I'd hate this to turn into one of those problems that people randomly experience for years to come since nobody can find the reason behind it.

[mean]

Does it work better with that version
http://avidemux.org/nightly/win_installer/avidemux_2.6.5_r8919_win32.exe

(32bits!)

[AQUAR]

There were some other posts by thany that seem to "maybe" point to issues attributable to file naming.
As a wild thought - is avidemux being run on a non English OS when these oversize issues arise?

[cliffshit]

- is avidemux being run on a non English OS when these oversize issues arise?

Use of WinXP SP3 32bit German here, and to date I had NEVER one of these problems.
I mostly encode in 2-pass mode with an average bitrate, and it always works perfect.

Maybe a clean install and deleting all avidemux directories and registry entries could help?

[AQUAR]

Luckily very few seem to have this random oversizing issue.
Reasons for inconsistent/odd behaviour like this are hard to trackdown, especially
if it isn't reproduceable by those able and willing to investigate.

[thany]

There were some other posts by thany that seem to "maybe" point to issues attributable to file naming.
As a wild thought - is avidemux being run on a non English OS when these oversize issues arise?

English language OS, Dutch locale setting. US-int'l keyboard layout.

Maybe a clean install and deleting all avidemux directories and registry entries could help?

I already tried that. Meaning a wipe of the directory in Program Files, and trashing the one in the user profile. I think that's all there is to throw out. Perhaps I missed something? If it might possibly help, I do like to know where else to look for files to throw away.

Another thought: Avidemux is very much dependent on CPU features, as proven by it prominence in the preferences dialog. Would it help if some of those are disabled (and consequently, how do I do that), and/or would it help to know which CPU's I'm running?
One pc that's showing this problem is running Windows XP in a ESXi virtual machine on three of the four cores of a Core i5-3470S, without HTT, but VT-d enabled in the BIOS. No real GPU to speak of, being a VM.
Another one is a real machine, running Windows 7 x64 on a Core i7-2630QM, with VT-d and HTT enabled in the BIOS. GPU is an AMD FirePro M5950.

(I'm sure the GPU or the VT-d setting has nothing to do with Avidemux, but one never knows, I suppose).

Luckily very few seem to have this random oversizing issue.
Reasons for inconsistent/odd behaviour like this are hard to trackdown, especially
if it isn't reproduceable by those able and willing to investigate.

Luckily for them
One thing we know is that the problem is not specific to a video file. It happens all the time. Another thing we know is that a clean install doesn't help, because I tried it on a machine that has never had any version of Avidemux installed. We can also conclude that some pc's tend to show this problem and others don't, but (at least according to my findings) such pc's may be very different from one another, while two pc's that seem very similar may produce very different results.

Will try again later today with another newer version. Will post back results when available.

[thany]

Same problem in r8919. I tried the aforementioned 32 bits installer on Windows XP.

Disabling CPU features in the preferences (assuming that actually does disable them - I can't check if it does anything) makes no difference at all. So we have that at least.

[AQUAR]

It happens all the time but only on a few PCs (mostly yours!).

Hence, your best bet to resolve this is by trying to isolate what is different with your PC's from the norm.
Try running avidemux in "XP mode without the Dutch language pack" on your windows 7 64 bit machine.

The fact that this thread exists might flush out more people with this issue, that would give it some impetus.

[mean]

If you disable threading, i.e. encode with only one thread, does it work ?

[thany]

@AQUAR
I don't have the Dutch language pack (assuming you refer to the type of langpack that transforms an English Windows into a fully translated Windows). Just the locale setting is Dutch, so I will see proper decimal points and currency symbols and stuff like that. Windows is still fully English from tip to toe.
I can, however, do a complete virgin install of an English Windows 7 with US locale on a separate physical computer and see what that does. If that reproduces the problem, would you believe my pc is not causing it?

@Mean
Trying it now. It'll take a while, though.

/edit
Okay, so there seems to be an issue with that, too. When I set it to Multi-threading: disabled, it still uses all CPU cores simultaneously. When I set it to "custom", it doesn't allow setting it to 1. 2 is the minimum. But even if setting it to 2 threads, it still uses all 3 cores. On top of that, in all situations the original bitrate-problem persists (as expected, because the threading option appears to do nothing).

/edit2
Also tried to force it by setting an affinity mask in the task manager (and Multi-threading: auto, in the preferences). It appears to have started only a single thread, because resetting the affinity mask to all three cores doesn't improve processing speed and keeps cpu utilization around 33-35%. But, it doesn't do anything for the bitrate problem.

[AQUAR]

@ thany
I really don't have any belief about what is causing your issue.
BUT, the fact that I responded should tell you that I believe in the existence of the issue.
It might be caused by - avidemux - PC harware - the OS - a software conflict etc etc.

What is very apparent at this moment is that it is very uncommon.
That status might of course change if more endusers start reporting similar experiences.

Staying broadminded about any suggestions offered to help out is your best bet at the moment.

 

[thany]

Which is why I offered to install a brand new Windows on a separate physical box. I'll do that probably later today or tomorrow. It takes some time, but if it helps make avidemux better, than that's good.

In the mean time, do you have any idea about what kind of software might be conflicting? Then I can test that as well... I don't have a whole lot of software on the pc that's showing this problem, but maybe one of them is misbehaving. And now that I'm typing this, I realize I do have AVG installed and enabled on-write scanning (I'm sorry, I should have thought of this sooner)... I'll do some testing with (or without) that, too. After all, virus scanners are prone to cause weird things...

[AQUAR]

Excellent idea to start with a minimum number of variables - clean install WINDOWS 7 - full admin account - NTFS file system - short/simple file/user/path names (no ". ~"!) - just an english version - no other software - and put it in a standard folder (not the special security beefed up "programs" folders).

That is what I was doing a few weeks ago when I came looking for avidemux updates, and I am still working on it.