mp4 Audio Anomalies

legendofzub

Newbie Joined: Jan 07, 2015 20:12 Messages: 20 Offline

Solved by

May 29, 2016 15:54

Back in December, I upgraded to PowerDirector 14 Ultimate using PowerDirector 13 as a base. I ran into this issue then, but just went back to using 13 thinking it was either an issue that would be patched, or an issue with Windows 7. I've upgraded to Windows 10, downloaded the latest build, and the issue still persisted. Today, I uninstalled both 14 and 13, then reinstalled them, and the issue still persisted.

During playback, the audio sounds fine. However, when I produce an mp4 video, the resulting audio has a fairly large amount of static whenever there is audio. I've tried using quieter and more dynamically diverse tracks to no avail, so it definitely isn't clipping. The strangest part is that PowerDirector 13 doesn't have this problem, and PowerDirector. I've attached the original WAV file produced by Audacity, and the M4A files from PowerDirector 13 and PowerDirector 14 of a sample to show this issue. I would have attached MP4s, but the file sizes would have been bulkier than necessary. I also produced a file with PowerDirector 14 using the file produced with PowerDirector 13, which had the same issue, but the forum will only let me upload three files. All of the M4A files were produced with a bitrate of 384kbps selected.

I've tried using various input codecs, containers, and formats, including using a WAV file produced by PD14, but none of them solved the issue. I then tried using the file produced by PD13 as the file for PD14 to use since that would be as close to the output format as possible, but the PD14 output still had the same artifacts, so I think it's pretty safe to say that the input file format is not the problem.

While examining the resulting files, I noticed that the bitrate of the PD14 files were 385kbps while the bitrate of the PD13 file was 97kbps. After seeing that, I thought the issue could have potentially been that PD14 was locking the output bitrate by adding artifacts while PD13 allowed the bitrate to drop below the designated bitrate if need be. I couldn't figure out how to allow PD14 to allow a variable audio bitrate, so this is still a possible solution.

I've tried multiple profile settings for various codecs using an mp4 container, but none of them fixed the problem at all. For the H.264 codec, I also tweaked various settings in the .ini file to no avail. I've tried changing the audio to be a voice track. I've tried all of the TrueTheater Surround settings. I can't get anything to work.

I'll probably start editing in 14, produce the video, produce a WAV file, then put them together in PD13 until someone smarter than me can figure it out. I like all of the new features 14 brings, and I really want to make use of the program I bought... That's really a long process to go through just to get acceptable audio quality, though...

Power Director Ultimate 14.0.2820.0

Filename	Original.wav	Download
Description	Original WAV file from Audacity
Filesize	22605 Kbytes
Downloaded:	183 time(s)

Filename	PD14a.m4a	Download
Description	M4A file from Power Director 14 using Original.wav
Filesize	2827 Kbytes
Downloaded:	247 time(s)

Filename	PD13.m4a	Download
Description	M4A file from Power Director 13 using Original.wav
Filesize	723 Kbytes
Downloaded:	242 time(s)

stevek

Senior Contributor Location: Houston, Texas USA Joined: Jan 25, 2011 12:18 Messages: 4663 Offline

May 30, 2016 07:58

Thanks for the information. Perhaps it was too much backgrpound and scared other people off. I see several people have downloaded the attachments so maybe one will help.

I downloaded all three files and the audio quality was pretty much equal for both the wav file and the m4a files. NO static !

In the meantime, please attach the dxdiag.exe evaluation of your computer Thanks.

You can attach a 3-5 second sample of the video file. The forum should accept it if it doesn;t start acting up again.

This message was edited 3 times. Last update was at May 30. 2016 08:08

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CS2014

Senior Contributor Location: USA-Eastern Time Zone Joined: Sep 16, 2014 16:44 Messages: 629 Offline

May 30, 2016 09:13

Definitely attach the Dxdiag like Steve suggested.

Have you tried an audio file of mp3 format in the project and what are the results when you 'produce' that?

When you say 'During playback...' are you saying that when you see and hear it during 'preview' in the editing room?

CS PD13 Ultimate - Build 3516, WIN 8.1, 64 Bit, 16G RAM, Intel Core i5 4460, CPU @ 3.2GHz, NVIDIA GeForce GT720, Graphics Memory(total avail.)-4093MB
LG WH14NS40 Blu-Ray Drive

tomasc

Senior Contributor Joined: Aug 25, 2011 12:33 Messages: 6464 Offline

May 30, 2016 10:46

The audio sample files played okay in wmp. Mediainfo reported that the 384kbps was selected in both PD converted m4a files although PD13 produced one at ¼ the bitrate. I did not hear any static using normal volume levels. That is pretty much what Steve found.

JL_JL

Senior Contributor Location: Arizona, USA Joined: Oct 01, 2006 20:01 Messages: 6091 Offline

May 30, 2016 12:14

Quote:
I've tried using various input codecs, .......

Not sure what you mean here, can you share how you changed input codecs, I assume audio codecs associated with your source video file?

Quote: While examining the resulting files, I noticed that the bitrate of the PD14 files were 385kbps while the bitrate of the PD13 file was 97kbps. After seeing that, I thought the issue could have potentially been that PD14 was locking the output bitrate by adding artifacts while PD13 allowed the bitrate to drop below the designated bitrate if need be. I couldn't figure out how to allow PD14 to allow a variable audio bitrate, so this is still a possible solution.

I'm not sure I understand what you mean by adding artifacts. Nothing is really added during different sample bitrates that was not in the original audio steam. I see the anomaly as the opposite. At PD13, PD did not really appear to encode a pure bitrate audio. Say you selected a output of 384Kbps, you could get various bitrate depending on audio complexity. That was summarized here http://forum.cyberlink.com/forum/posts/list/39468.page#203924 and acknowledged by support in that thread. At PD13 this same anomoly existed but to me at PD14 I think CL corrected the anomoly, at least as far as I have seen. This is the effect you noted about the PD13 audio file you posted, it's really not 384Kbps as you desired, but 96Kbps. The PD14 audio file is a real 384Kbps bitrate file which you asked for.

I too found no discernable difference in the audio channels you posted. The playback effect you note might be a side effect of installed third party codec packages if you have installed some.

I've done some preliminary subtraction of the right channel of PD14a.m4a with the right channel of PD13.m4a and it's near silence, suggestion the two audio files are nearly identical and the reason several have posted they hear no static anomolies.

Jeff

ynotfish

Senior Contributor Location: N.S.W. Australia Joined: May 08, 2009 02:06 Messages: 9977 Offline

May 30, 2016 14:52

Hi legendofzub -

I downloaded your attachments for testing yesterday. After putting them through their paces, then re-rendering the "Original.wav" as m4a in both PDR13 & 14 (with bitrate set to 384Kbps), I couldn't hear any difference in your attachments or the files I produced here.

The reason I didn't respond at the time was I wasn't entirely sure my less-than-perfect hearing wasn't a factor!

I played back your attachments and the m4a files produced here in various media players.

MediaInfo does show some differences in how it reports the PDR13/14, but I couldn't consistently detect any audible difference.

Cheers - Tony
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legendofzub

Newbie Joined: Jan 07, 2015 20:12 Messages: 20 Offline

May 30, 2016 17:40

I'll generate the diagnostics file in a minute.

Quote: You can attach a 3-5 second sample of the video file. The forum should accept it if it doesn;t start acting up again.

It's more of an issue with my internet speeds than with the forum, and the video wouldn't benefit it.

Quote: Have you tried an audio file of mp3 format in the project and what are the results when you 'produce' that?
When you say 'During playback...' are you saying that when you see and hear it during 'preview' in the editing room?

Yes, I've tried using mp3 files. It has the same grumble, but with a noticeably poorer quality overall.
By "during playback," I indeed meant during the preview in the editing room, which is to be expected as it should have been playing back the original audio, but may have indicated that it wasn't PowerDirector misreading the file.

Quote: Not sure what you mean here, can you share how you changed input codecs, I assume audio codecs associated with your source video file?

Yes, I tried exporting the Audacity project using varous codecs and containers, such as various wav formats, mp3, and tweaked things like the sample rate.

Quote: I'm not sure I understand what you mean by adding artifacts.

It was just a hypothesis. I was suggesting that it may have produced the same way that PD13 did, checked the bitrate, and just added filler to end up with a file that has the desired bitrate. I tried outputting the audio clip with a bitrate of 95kbps, and if I remember correctly, the artifacts weren't there, but the quality was abysmal.

Quote: I too found no discernable difference in the audio channels you posted. The playback effect you note might be a side effect of installed third party codec packages if you have installed some.

That could potentially be the case, and I'll need to try it on a different computer. Would that affect playback through streaming the videos from YouTube, though? I suppose it could... I'm really hoping that's the case.

It may be one of those "once you hear it, you can never un-hear it" sorts of things. It's pretty faint, and sounds quite a bit like someone moving around in an old leather/pleather chair (I actually thought I heard in a PD13 render of a clip, but it turned out to be me shifting in my computer chair). I can imagine it getting really annoying in the same way that a dripping faucet, or the hum of a cheap power supply would.

legendofzub

Newbie Joined: Jan 07, 2015 20:12 Messages: 20 Offline

May 30, 2016 17:44

Checked through YouTube on a different computer, same problem, so I highly doubt it's a 3rd party codec issue during playback.

legendofzub

Newbie Joined: Jan 07, 2015 20:12 Messages: 20 Offline

May 30, 2016 17:54

Here's the DxDiag file with everythingI generally have connected during editing, with the exception of headphones and monitors.

I've been waiting for Pascal to launch to put together a decent desktop, so if that would be a fix, that'd be nice. I wouldn't be surprised if part of it was a result of my old hardware.

Filename	DxDiag.zip	Download
Description
Filesize	16 Kbytes
Downloaded:	224 time(s)

legendofzub

Newbie Joined: Jan 07, 2015 20:12 Messages: 20 Offline

May 30, 2016 18:26

Sorry to everyone for the consecutive posts. Last one before someone else responds.

Quote:
I've done some preliminary subtraction of the right channel of PD14a.m4a with the right channel of PD13.m4a and it's near silence, suggestion the two audio files are nearly identical and the reason several have posted they hear no static anomolies.

Is this what you got? To me, the voice is basically gone, but the noise is still there, and almost completely burries the remains of the vocals.

Filename	Subtraction.zip	Download
Description
Filesize	10642 Kbytes
Downloaded:	174 time(s)

JL_JL

Senior Contributor Location: Arizona, USA Joined: Oct 01, 2006 20:01 Messages: 6091 Offline

May 30, 2016 19:07

Similar, however I only did a single channel, yours appears to be dual channel. Not knowing the real source of your audio I didn't take the chance of L and R channels not being identical. Ideally this subtraction would be silent but some error existed for me as your two clips are not the same bitrate so some sampling error to start with. Additional, not identical amplitudes so I had to normalize each right channel to do a proper subtraction comparison.

Bottom line, peak amplitude of basic R channel audio about ~-20db, peak audio of subtracted right channels, ~-50db. That's a amplitude difference of 30:1 and these older ears probably couldn't catch that amplitude error of "static" mixed into a sound track, nor probably 100% of the other seasoned users here!

Jeff

legendofzub

Newbie Joined: Jan 07, 2015 20:12 Messages: 20 Offline

May 30, 2016 19:38

The original audio was recorded as mono, so theoretically, the channels are identical. I originally did it with just the right channel as you did with yours to replicate the "experiment" as best I could, and it still had the "static." Since they were different bitrates, and different programs that produced them, I expected the small amount of desired audio to remain as it did.

As I said, it IS a tiny, almost completely unnoticeable amount of noise relative to the important audio, but it's perceptible enough to potentially drive away potential viewers. Do you hear it now, or am I just crazy?

Considering it only occurs when other sounds are also occuring, I think it may be a result of residual noise that wasn't removed during noise removal of the original recording. It seems rather strange, though, that the program would amplify that noise, doesn't it? How would that even happen? Could it be aliasing or something similar?

tomasc

Senior Contributor Joined: Aug 25, 2011 12:33 Messages: 6464 Offline

May 30, 2016 22:07

Quote: As I said, it IS a tiny, almost completely unnoticeable amount of noise relative to the important audio, but it's perceptible enough to potentially drive away potential viewers. Do you hear it now, or am I just crazy?

Legendofzub – I think you hit the nail on the head on this one. Your other posts about being a younger generation engineering student brought back memories when I used to do dolby b and c cassette original recordings on metal tapes. With enclosed type headphones I could hear people talking, chair movements, noise, etc. not normally heard when played back on room speakers.

There are trained musicians who can hear low im distortion that may be acceptable to most people. Some people do hear things that may be barely noticeable to others.

RickMcKC

Newbie Joined: Jan 01, 2014 15:27 Messages: 22 Offline

Aug 07, 2016 16:07

I have noticed the same issue as the original poster for months. It drives me crazy as we produce weekly videos for church services using PD14 and I hear the "scratchy" audio every week. Grrrrr.

As an experiment, this weekend I completely reinstalled W10 Pro and then no other programs except for PD14. Then I removed it and installed PD13.

I produced an MP4 file (1080p/59.95/192Kb) from both programs using exact same source material. Again, PD13 sounds fine while PD14 has that distortion.

Pretty disappointed to see other folks having this issue for months and yet no patch issued to fix it.

I'll stick with PD13 for now and will be very hesitant to upgrade when PD15 comes out. I will probably look at alternatives.

legendofzub

Newbie Joined: Jan 07, 2015 20:12 Messages: 20 Offline

Aug 12, 2016 13:05

Rick,

I have both 13 and 14 installed and haven't had any stability issues. My "solution" is to do all of the editing in 14 since it's so much better in that regard. I then create the .MP4 file, but also create a .WAV audio file with the same project. With both of those, I open up PD13, drop them both at the begining, mute the .MP4, and produce the finished .MP4 using the same profile settings that were used to make the intermediate .MP4. It only takes a couple of minutes longer, give or take your system's load time, since the second production is done with SVRT. That way you get all of the benefits of PD14 editing without the nasty audio problems.

Hopefully they hammer that problem out before 15. Ideally, they'll patch 14 because I really would rather not upgrade unless there are significant improvements... The entire reason I chose PowerDirector was due to its one-time fee. Yes, Cyberlink has the best forum for help and support that I've ever seen, but the subscription based editors seem to have more tutorials and even quite a bit of open-source resources and plugins.

RickMcKC

Newbie Joined: Jan 01, 2014 15:27 Messages: 22 Offline

Aug 13, 2016 00:54

Hey, thanks for the suggestion. I will give it a try next week!

gbross

Newbie Joined: Mar 29, 2011 11:44 Messages: 11 Offline

Nov 19, 2016 22:33

I notice this distortion as well. I just upgraded to 15 and the static/distortion problem is still there.

when in H.264.

I make music videos. I produce a WAV file in ProTools which I sync with the video in Powerdirector. When listening during video editing all is fine - full fidelity - just like it was in ProTools. But when I produce the video ih H.264 with MP4 the audio is distorted and not as full sounding.

Big problem.

I am forced to produce in my H.264 files in M2TS and all is fine audio wise - full fidelity. The difference I see in M2TS is that it uses Dolby Digital as opposed to AAC in MP4 and M2TS has an audio bit rate of 256 as opposed to the MP4 of 384.

Customizing the MP4 to a bit rate of 256 and producing the video does not solve the problem.

I upload these M2TS finished videos to YouTube and all is well.

Question? What are the pros and cons of me going the M2TS route instead of MP4 when in H.264?

This message was edited 2 times. Last update was at Nov 19. 2016 22:38