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Squeeze 4.5 Audio Glitches (consistent and annoying!)

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Roger Matthews
Squeeze 4.5 Audio Glitches (consistent and annoying!)
on Dec 30, 2007 at 11:25:08 pm

I've just started to use Squeeze 4.5 (upgraded to 4.5.700.1 yesterday) and have had no problem converting DV AVI files to Power Point WMV files for my job.

However, I've started making YouTube flv files (22khz 32kbps mono audio, 20fps 310kpbs video with a keyframe every 45 frames) . They look great, but strange audio glitches keep popping up! I've ran some troubleshooting, and two scenarios pop up:

1) I feed Squeeze a regular DV AVI file (4:3 ratio, 48khz audio) and it starts looping the audio at the end of the file. Everything's perfect, and then the last twenty seconds of audio have this weird looping delay effect.

2) I convert the source DV AVI file to 44khz. Squeeze no longer gives me a looping delay effect - great! But now the audio seems about 2db louder (?!?!), so anything in the -2db range or so distorts.

Now I doublechecked, and my converted 44khz source file does NOT clip. The source files are definitely fine, and Squeeze is doing something wacky.

My question is - Squeeze is an expensive program. These seem like pretty basic glitches that I can consistently reproduce every time (and as I mentioned, I upgraded to the latest version while troubleshooting). I've tried adjusting the audio bitrate to 128 with no luck. I feel out of options!

Please help! (and many thanks for reading my longwinded post)


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Aharon Rabinowitz
Re: Squeeze 4.5 Audio Glitches (consistent and annoying!)
on Dec 31, 2007 at 2:43:48 am

what is your input audio rate? Is it 48 compressed to 44? That could be the problem. Can you create your original at 44?

It's also possible it's a bug. You may want to email (or even call) them to discuss it.



Aharon Rabinowitz
Email: arabinowitz (AT) yahoo (DOT) com
All Bets Are Off Productions, Inc.
Creative Cow After Effect Podcast
Internet Killed the Video Star: A Guide to Creating Video for the Web


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Roger Matthews
Re: Squeeze 4.5 Audio Glitches (consistent and annoying!)
on Dec 31, 2007 at 2:51:11 am

Thanks for the response! I'm planning on getting your DVD on compression once I get some more money :).

I've tried creating the original at both 48khz and 44khz - my point was that both rates cause different problems. A 48khz source causes the delay loop effect, and a 44khz source (while fixing the delay effect) makes the audio louder and distorted.

Not a bad idea about reporting it. I'll do some more testing and see what happens. Their docs say there is a known bug with 48khz source audio, but claim that changing the source to 44khz fixes it (which I would argue is not the case).



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Daniel Low
Re: Squeeze 4.5 Audio Glitches (consistent and annoying!)
on Jan 3, 2008 at 12:37:08 pm

Roger,

I question your use of 20fps for the Youtube video. Frame rates should always be an integer division of the source frame rate. In other words if the source is 30fps then you should only use 15 and 7.5fps. If the source is 25fps then you should only use 12.5 and 6.25 etc. Anything else will result in jerky playback.

Squeeze is ok but not the greatest application out there, it may be worth downloading a trail version another transccoding application to see if the problem you have with the audio persists. I'd recommend either Episode on the Mac or Procoder on the PC.


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Aharon Rabinowitz
Re: Squeeze 4.5 Audio Glitches (consistent and annoying!)
on Jan 3, 2008 at 3:24:29 pm

Wow. I completely missed that. I have to admit I didn't read that first post carefully - I shouldn't be looking at this stuff while on vacation. I didn't give this the attention and focus it deserved.

Since you are using Squeeze, you should be aware of the option for frame rate in there. You may notice the 1:1, 2:1, and 3:1 option. This is there to keep you from making a bad mistake, as the one Dan talks about.

There is/was? a 48Khz audio bug with Squeeze, but I hear varying reports about it from different users. I don't experience that problem anymore but some do, and I'm not sure why.




Aharon Rabinowitz
Email: arabinowitz (AT) yahoo (DOT) com
All Bets Are Off Productions, Inc.
Creative Cow After Effect Podcast
Internet Killed the Video Star: A Guide to Creating Video for the Web


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Roger Matthews
Re: Squeeze 4.5 Audio Glitches (consistent and annoying!)
on Jan 4, 2008 at 7:37:56 am

Thanks for the idea about the framerate (I was only using 20 because it was in a doom9 YouTube guide).

However, I tried On2 Flix Pro using the same settings (20fps and all), and it worked fine on the first try! Here are the results -





I find this strange since my copy of Squeeze uses On2's VP6 codec. I know I wasn't using VP6 but regular FLV1, but still.

Squeeze just continued to give me problems - I tried a source of 48khz, 44khz, and even lower resolutions (I believe 32khz). 32khz distorts, just like 44khz. On2 Flix Pro didn't complain at all, it took my 48khz and gave a clean render on the first try.

Thanks for the recommendation for ProCoder. I thought Squeeze was the only option for PCs, I might check out a trial of that one for my next project.


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Aharon Rabinowitz
Re: Squeeze 4.5 Audio Glitches (consistent and annoying!)
on Jan 4, 2008 at 12:22:41 pm

Cool. There are times where on of those 2 works for me when the other doesn't. I have often found it's related to the codec, but you never know what's going to do it.

I should point out that you need to deinterlace your video. Video for the web should be progressive, not interlaced. Interlacing is for broadcast only.

You can see interlacing in any are of high motion - those jagged lines and distortion at every other line where there is fast motion.

When you captured your video, it captured it with fields (or the video camera filmed with fields). Or it's possible your footage is progressive and you;re output settings are set to export video with Fields (probably Lower Field First).

I don't work in FCP, but in you're export settings, somewhere there will be a setting for rendering (exporting) without fields. Make sure it is set to that, and not Lower Field FIrst (LFF) or Upper Field First (UFF).

Then re-compress.

Oh, yes, it's possible to deinterlace in squeeze, Flix and other compression programs, but they won't do as good a job as you're video editor which will usually have a few different option on how to de-interlace based on the type of footage and/or motion.



Aharon Rabinowitz
Email: arabinowitz (AT) yahoo (DOT) com
All Bets Are Off Productions, Inc.
Creative Cow After Effect Podcast
Internet Killed the Video Star: A Guide to Creating Video for the Web


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Daniel Low
Re: Squeeze 4.5 Audio Glitches (consistent and annoying!)
on Jan 4, 2008 at 4:57:19 pm

Indeed there are field issues/errors in that Youtube clip, but they look worse than just failing to deinterlace would produce. It would seem like the source for the encode has gone through a number of format changes where the fields may have been 'messed' with. I could be wrong but the combing artefacts seen in the clip look to me as too 'fat' to be regular video fields.

Aharon, sorry but I have to beg to differ (again!) with regards to the quality of deinterlacers when comparing video editing software vs dedicated transcoders.

In my experience most video editing packages either drop a field or blend when deinterlacing a clip. Most decent transocders (and certainly my two favorite ones, Episode & Procoder) offer advanced motion adaptive/edge detecting methods, as well as field interpolation, along with the usual drop field and blend.

Blend nearly always produces a soft image, drop field reduces your resolution in half (it throws away half the picture). Motion adaptive and interpolation methods provide the best results.

Squeeze has, IMHO, a pretty bad deinterlacer, it's somewhere inbetween drop field and interpolate. I've never had a good result when using it.

Check out this great resource on deinterlacing:
http://www.100fps.com/



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Roger Matthews
Re: Squeeze 4.5 Audio Glitches (consistent and annoying!)
on Jan 14, 2008 at 11:00:47 pm

I know it's a little late now, but I checked the source AVI and it is indeed 24pa (with 2-3-3-2 pulldown). My only guess is that the 'interlacing' came from pulldown conversion?





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Roger Matthews
Re: Squeeze 4.5 Audio Glitches (consistent and annoying!)
on Jan 6, 2008 at 11:11:10 am

Oh, man. How embarassing.

My friend noticed the fields as well. The video was shot 24p, but I must have foolishly rendered lower field first (I'm using Vegas 6, and the program usually defaults to lower field first when not specified).

I chalked the fields to compression problems, but the interlacing would make a lot of sense. When I have some time I'm going to look into what settings I used for the render.




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