AC3 audio editor.

[reboot]

In my neverending quest for free (and easy to use) tools, I finally stumbled upon Nero Wave Editor. Something I've had for a long time, and never used.
With the free AC3 plugin here: http://neroplugins.cd-rw.org/
I can now import, and change, fix, filter, equalize, whatever, all my AC3 DVD audio files, and then save them as AC3.
If you have Nero 6, the wave editor is a freebie
It will also load up just about any type of audio (with the plugin) and save it as AC3.
Not the fastest, but FAR cheaper than Soundforge!

[Stormin Norman]

Nice find, ive only tinkered with wav files in that program.

[CSULB71]

I have Nero Express 6 that came with my DVD burner, and it includes several "extra" apps (including Wave Editor), but when I click on the icons I get a message saying my current license does not allow use of the program. The Nero suite (which included other apps that I chose not to install) came on an OEM installation CD, so why would they include apps files that I can't use but technically paid for? Or is that what the "Express" part is all about? Does anybody know if there is a way to turn on the extra apps, like maybe a registry fix?

[Baldrick]

but ffmpegs ac3 encoder isn't the best.

[reboot]

but ffmpegs ac3 encoder isn't the best.

Very true, but at least one can manipulate the files now, and not have to go through extraction, conversion, fixing, saving, and transcoding, using 3 different apps

[daphy]

Does anybody know if there is a way to turn on the extra apps, like maybe a registry fix?

purchase a UltraEdition key and paste it in the smartstart application by clicking on the button with the fire on it

[drjtech]

... so why would they include apps files that I can't use but technically paid for?

Technically you haven't paid for them. They are dangled before you as an enticement to purchase the full version.

-drj

[CSULB71]

Does anybody know if there is a way to turn on the extra apps, like maybe a registry fix?

purchase a UltraEdition key and paste it in the smartstart application by clicking on the button with the fire on it

Well, OK, then I don't need to use Nero's Wave Editor that much. For what little audio editing I do, I've had good results with "Audacity", and of course, the price is right

[DJRaca]

A very nice ac3 editor without needing any new plug-ins is included in Nero 8 WaveEditor

Sony Sound Forge 9 does not open ac3 files. It can just export to that format. Pity

[darkflux]

ironically, the latest Sound Forge will open VOB's and MPG's with AC3 audio. if you already have Sound Forge, a workaround would be to mux an mpeg file with your AC-3 file, and open the MPG file in Sound Forge. you can then edit all 6 (or however many) channels of the AC3 file, either individually, or separately. Womble MPEG Editor will mux nearly any file type into an MPG or VOB file, without re-encoding.
if you need to do the opposite, for some reason and pull the AC3 file out of the MPG, VirtualDubMod will do it. just open the VOB or MP3 with it, and choose "Stream List > Demux".
-df

[Nelson37]

Thanks much for this post, this does EXACTLY (well almost) what I have been looking for. The ability to display an AC-3 as a waveform.

Now if it could only do two at the same time for comparison....

[darkflux]

hey Nelson. you should be able to do that. just open two copies of Nero Wave Editor. Sound Forge can do it natively, without opening multiple copies of the program, just mux the AC3 with some MPG file you have lying around (if you have SF).

[Nelson37]

Yeah, I've thought of that, I'm trying to nail down some pretty small time differences, on the order of 0.8 seconds over a one hour file. Need some pretty fine control.

Sound Forge might be worth a look-see.

[darkflux]

yeah, Sound Forge is probably abit better in terms of features and usability, but it costs an awful lot. it will definitely do most audio altering capabilities. if you wanna see what it can do, check here: http://www.sonycreativesoftware.com/soundforge/compare
for multiple file editing/combining/comparison directly though, Acid (also from Sony) can't be beat. it has the 2 files directly side by side. only 2 catches though, it doesn't work with AC3, unless of course you do the whole muxing workaround like with Sound Forge. also, you can only see 2 channels, although apparently it preserves all 6 (5+1), and will save it as 5.1 AC3, but only displays 2 of them. not sure what that means for editing, but thought it was worth a meantion.
i had another idea, and thought i should bring it up here too. if you took the AC3's and broke them down into 6 separate WAV files (each), you should be able to open each in it's own editable channel in Acid, and could even have each corresponding speaker next to each other, for example, Front Left 1 and Front Left 2 (from each file). you can separate an ac3 file using BeSweet, if you need to. it's a complex program, but there's a GUI for it, which allows for much customization of how to convert the AC3, and will even make a standard 2-channel WAV when needed.
anyway, more knowedge for ya brain
-df

[gadgetguy]

If you're going to convert to wav, then you might as well use Audacity.

[darkflux]

Audacity is a VERY good sound capture program. and it's FREE too

[gadgetguy]

Maybe I misunderstand, but I thought the point of this discussion was to be able to edit AC3 files, not capture, play, or convert them, but directly edit them. Audacity cannot handle AC3 directly, (unless there's a plugin that I'm not aware of), but once you convert an AC3 file to a multi-channel wav or multiple wavs, there isn't much Audacity can't do as far as editing. It can then export to multichannel wav, which can then be encoded back to AC3 using your encoder of choice. Audacity is a fine editor, not just a capture program.

[Nelson37]

What I've been doing is converting the AC-3 to 6 waves, and using the two front channels to compare to an MPG file with stereo MP2 in Vegas. Works well in being able to expand the view, easily cut and arrange the WAV files, zoom in and align with good presicion. Vegas also has a compliant AC-3 encoder, which is why I got it in the first place.

Originally, I was stretching the 6 waves to match the MPG audio and then re-encoding to AC-3 to match the original audio track, as I had believed my problem was an audio file that was slightly short. I have recently discovered that the REAL issue is that the video is too long. This discovery doesn't really offer a better solution, but is really making me wonder WTH is causing this.

I am combining HD-audio with the HD-video downsampled at the box and captured as MPG thru the S-Video port. The resulting video is longer than the original HD by approximately 1 second per hour, though this is somewhat variable.

Sound Forge doesn't seem to give a waveform display with a 6-channel AC-3, though I haven't dug into it too deeply. Two-channel AC-3 does display as desired, while this is OK for testing its not worth the hassle if all 6 channels are not present.

Concerning Acid and the need to mux with an MPG file - can it display TWO such MPG + AC-3 files in the same window?

[gadgetguy]

I have a theory about your video being too long, but it's not fully formed and is based on a problem that I was having converting my HD files (captured with MyHD), to standard DVD. My tp files have frame based irregular pulldown and many of the tools I was attempting to use didn't correctly honor those pulldown flags. After discussions in this thread I now properly get all of the frames, but still have not found the perfect solution to IVTC back to 23.976 fps. In your case my theory is that the problem involves that irregular pulldown issue.

[darkflux]

@gadgetguy: wow Audacity sure HAS changed since the last time i used it, just a couple years ago! yeah, it does everything pretty much just the way Sound Forge does, and, except for a few "high-end" features that most folks won't miss, they've got pretty much the same features! definitely keep it on my roster...
sorry, wasn't trying to mislead anyone, i've changed my post

@nelson37: Acid doesn't do any different than Sound Forge, it still opens just the 2 channels for editing. in fact, if you have Vegas, it should already allow you to open multiple audio files for comparison. Acid is mostly for mixing audio files, if i'd known you had Vegas i wouldn't have mentioned Acid, i was just thinking about the audio.

as far as video capture, you really need a fast system to pull off a decent capture, especially so with HD video. i've got an AMD Athlon64 3200+ and it does OK, but it really depends alot on the hardware you use, too, as you may know.
are you using your ATI card (from your profile) to capture the video, or do you have another box to handle the downconvert? i used to have one, but the ATI capture system is really not fast enough to capture anything other than standard video, even WITH a faster system. i ended up getting an external box for capture, and haven't had a problem since. kinda hard to find a decent one cheaply though. using hardware instead of software for video capture usually speeds things up for the PC, so that all it has to do is save the data, and tends to keep things more stable...

[Nelson37]

Interesting theory and post, gadget. But I'm not sure it applies to what I am seeing.

What I am capturing is HD programs, thru the S-Video port of a tuner box. Formerly did this using an HD satellite receiver. Am using an AIW card with IVTC on, this gives an MPG with stereo audio, perfect synch.

On the same box, I also capture the AC-3 audio thru SPDIF. It is this file which is out of synch.

Recently, I tested capturing, on another PC, at the same time, the HD stream using a Hauppage 1600 card. HD video and AC-3 audio in synch.

The SPDIF captured AC-3 and the Hauppage AC-3 are identical, or nearly so. I compared these to test if the problem was with the SPDIF capture or post processing.

While I am running a pulldown removal, I would think that if this was a problem, the MPG file would loose synch. Also, that the problem would not be so consistent. Also, am pretty sure I tried a few without the pulldown removal, no change. May have to re-run this test.

I guess it's possible that the ATI card drops audio frames to maintain synch when the video telecine has an irregular pattern. But, over a dozen or so tests. movies, episodic TV, different channels, for this irregular pattern to loose one second per hour, seems just "too regular an irregularity". I should note that the time measurement does vary slightly and is derived from visually comparing the audio waveforms. Plus or minus about 0.25 seconds or so.

The other possibility revolves around the downsample of the HD video, AND the AC-3 audio. Two different tuner boxes seem to produce a video and audio that is just slightly shorter than the original HD source.

One thing that may be a clue, or just a coincidence. If you have ever listened to a program's digital audio while watching in SD, and noted the audio synch slightly off, that is about the amount of de-synch I am seeing. However, it is gradually increasing, not constant. I manually synch the beginning and the problem is not noticeable until about a half-hour in, more or less.

Sorry to ramble on but this is really puzzling.

[darkflux]

hey Nelson, was that Hauppauge card the WinTV-HVR-1600? if so, that might explain how it didn't have issues, it's separate from the video card, meaning it didn't have to handle both your PC's video AND the capture process, so it wouldn't drop frames or anything.

[Nelson37]

Yes, that's the card, and I understand about the frame droppage issue.

But, I just can't see how random frame droppage would be so consistent over so many captures. I have experienced the "short" AC-3 file on about 2-3 dozen seperate captures, Enterprise episodes, full-length movies, different channels, first on Satellite and now OTA.

While there is a measurement issue, the error is always very, very close to the 0ne-second per hour mark. Never much higher, never much lower. What the Hauppage card test did was to provide a Known Good sample to test against.

Will do some more testing, perhaps without pulldown on, count frames in Vdub, etc. Any suggestions, from anyone, as to where else to look and/or other methods to examine this issue? Any ideas as to what mechanism could be causing this? I'm thinking maybe something as simple as a slight framerate difference.

[gadgetguy]

Like I said, it wasn't a fully formed theory. I just thought I'd throw it out there, but after reading the full scenario, I agree that it doesn't seem to be the issue. Unfortunately, I don't have any other suggestions...

[carbonunit]

I just started using Nero Wave Editor 4 to edit 5.1 ac3 audio from movies. Problem is the program will only load the first 40 minutes of the AC3 file. Anyone out there know why? I would greatly appreciate the answer.
Thanks

[darkflux]

@ Nelson: try capturing 15 fps, and see if the audio matches then. if it does, the it's a framerate issue, if not, maybe something else.


@carbonunit: my Nero Wave Editor can open a 2 hour ac3. maybe your ac3 is corrupt or wasn't extracted properly...

[Alex_ander]

ironically, the latest Sound Forge will open VOB's and MPG's with AC3 audio.

Thanks for the idea, I didn't know about it.

if you already have Sound Forge, a workaround would be to mux an mpeg file with your AC-3 file, and open the MPG file in Sound Forge.

It appeared to be even easier. Renaming .ac3 to .mpg or .VOB makes it work the same!!!

[Killer3737]

I was going to start a new thread but found this one and thought it was pretty relevant.

Basically, i was wondering if anyone knows of a program (freeware or payware) that will open, normalize, and save an AC3 file WITHOUT re-encoding it? I got an AC3 plugin for Adobe Audition that i thought would work, but that was still re-encoding the output AC3 file.

Cheers

[AlanHK]

I was going to start a new thread but found this one and thought it was pretty relevant.

Basically, i was wondering if anyone knows of a program (freeware or payware) that will open, normalize, and save an AC3 file WITHOUT re-encoding it? I got an AC3 plugin for Adobe Audition that i thought would work, but that was still re-encoding the output AC3 file.

Cheers

I'm pretty sure there is no such app. I was looking for a while, while you can do it losslessly for MP3 (eg, MP3Gain), no one seems to have a way to simply change the volume of an AC3 without reencoding.

[Killer3737]

I was going to start a new thread but found this one and thought it was pretty relevant.

Basically, i was wondering if anyone knows of a program (freeware or payware) that will open, normalize, and save an AC3 file WITHOUT re-encoding it? I got an AC3 plugin for Adobe Audition that i thought would work, but that was still re-encoding the output AC3 file.

Cheers

I'm pretty sure there is no such app. I was looking for a while, while you can do it losslessly for MP3 (eg, MP3Gain), no one seems to have a way to simply change the volume of an AC3 without reencoding.

I'd come to that conclusion aswell, and it's surprising, seems it such a simple process, and a lot of Digital streams have low volume.

Ah well, thanks anyway, one day maybe....