MP3 Audio "save as" options and LAME

GoldWave general discussions and community help
Yelnoc4
Posts: 34
Joined: Mon Apr 04, 2011 7:50 pm

MP3 Audio "save as" options and LAME

Post by Yelnoc4 »

I'm confused about the MP3 options when saving a sound file.

In the "attributes" popup, there is a "VBR Quality" dropdown. These values match up with LAME's "-v [0-9]" settings, correct?

LAME's -V settings, as listed at http://wiki.hydrogenaudio.org/index.php?title=LAME show a "Target Kbps" for each setting. GoldWave's popup also has a "Bitrate Range".

My question there is, "who wins"? Does GoldWave send both the -V switch and a target bitrate to LAME? Is there a way to see exactly what the command line to LAME looks like?
DougDbug
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Joined: Wed Feb 16, 2005 3:33 pm
Location: Silicon Valley

Re: MP3 Audio "save as" options and LAME

Post by DougDbug »

:? Good question! I've been confused by that too!!!

I just did an experiment and "V" wins. I choose "V0" and set the max & min to 32,000. For this particular file, the calculated average bitrate comes-out to ~198kbps. This quick expermint makes me think that GoldWave is ignoring those settings. Feel free to repeat the experiment... I'm not 100% confident that I did everything correctly. Bitrate is directly related to file size... Different settings should give you different files sizes, if they are doing what we think they are doing...

In the past, I've choosen the widest range to allow the encoder do the "thinking". I still think this is the "safest" approach... The idea behind lossy compression is that the encoder knows what data can be thrown-away while maintaining sound quality, and it's usually best not to manually constrain what it's doing. It's similar to JPEG... You could reduce the size of an image file manually by simply reducing the resolution, but JPEG is smarter and gives you better quality for a given reduced file size.

You can approximate bitrate with the following formula (or switch the formula around to calculate file size):
Bitrate in kbps= (140 x File Size in MB) / Playing time in minutes

GoldWave doesn't allow access to all of the LAME settings, but here's the (official?) reference. According to that website, there are two variables (-b and -B) that do exactly as you would expect and constrain the bitrate-range. They recommend that you don't use any maximum setting unless your playback system has limits, but GoldWave doesn't allow you to leave it blank.
Gord
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Joined: Thu May 21, 2009 4:26 pm
Location: Canada

Re: MP3 Audio "save as" options and LAME

Post by Gord »

Thanks, Doug. I am unclear on those GoldWave settings myself. In fact, I started to compose a reply to the other thread last night but then I abandoned it when I realized that I really didn't know what I was talking about.... :?
piano nick
Posts: 423
Joined: Wed Jun 16, 2004 8:33 pm

Re: MP3 Audio "save as" options and LAME

Post by piano nick »

I've been away for quite a while (forgot my password and received a new one).

I'm also confused about something:

When converting a WAV to MP3, there are many choices, but I'm only concerned about the differences in the following:

1) Layer - 3

2) Layer - 3 ACM

It's been so long since I downloaded the codecs, that I forget where I got them, but I seem to remember "finding" a not totally legal Fraunhofer codec that was a pro version or something like that.

Is this what the ACM is?

Also, by searching today, I found: "Fraunhofer.MP3.v3.4.PRO.ACM.CODEC"

Can I and should I install this?

Nick
DougDbug
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Joined: Wed Feb 16, 2005 3:33 pm
Location: Silicon Valley

Re: MP3 Audio "save as" options and LAME

Post by DougDbug »

Welcome back Nick! I had kind-of assumed you'd moved-on to something more professional like Adobe Audition or SoundForge.
Also, by searching today, I found: "Fraunhofer.MP3.v3.4.PRO.ACM.CODEC"

Can I and should I install this?
No. Just stick with LAME for encoding, and whatever ACM MP3 decoder that comes with Windows. (GoldWave uses both of these by default.)

MP3 Pro is a different standard that never seemed to catch-on. (I don't think portable players like iPod can play it.) As I understand it, MP3 Pro was supposed to be better compression (smaller files) at low-bitrate settings, but I at high-bitrate high-quality settings, I think regular MP3 has better sound quality.

I beleve ACM (Audio Compression Manager) is a Windows protocol for communication between CODECs & applications.

If you do and advanced search on the forum for "ACM" with "GoldWave Inc." as the author you can find lots of information.
piano nick
Posts: 423
Joined: Wed Jun 16, 2004 8:33 pm

Re: MP3 Audio "save as" options and LAME

Post by piano nick »

Thanks Doug, I think I'll just leave well enough alone, and stay with what I have (it works).

No I didn't move on - I've done quite a bit of photography the past four years.

I use Pianoteq for the sound with my digital piano (never have liked any of the onboard sounds of DPs), and I'm a beta team member, and this has taken some extra time over the past three years.

I'm still a Goldwaver, and often suggest it to others on other music forums. It still astounds me how people post waves/mp3s and the maximum level is -8dB or lower.

BTW, to what level do you max waves? I've been using -0.3dB or -0.5dB.

Nick
donrandall
Posts: 550
Joined: Wed Dec 01, 2004 11:06 pm
Location: Denver, Colorado

Re: MP3 Audio "save as" options and LAME

Post by donrandall »

Hey Nick — It's good to have you back among us!

You should be able to save at 100% - or - Zero (0). But, for no good reasons I could never explain, I usually save things at -1.
piano nick
Posts: 423
Joined: Wed Jun 16, 2004 8:33 pm

Re: MP3 Audio "save as" options and LAME

Post by piano nick »

donrandall wrote:Hey Nick — It's good to have you back among us!

You should be able to save at 100% - or - Zero (0). But, for no good reasons I could never explain, I usually save things at -1.
Thanks Don:

I primarily spend time with Pianoteq for piano sounds, but of course still use Goldwave extensively.

I'm confused by your statement, "usually save things at -1". The only options I have are:

http://www.box.net/shared/opd67avp0y

It starts with Layer 3, 48,000 kHz, 320 kbps, then runs through lower frequency and bit rate options, then goes to: Layer 3 ACM, 48,000 kHz, 320 kbps (and runs through lower frequency and bit rates).

The last option is "custom".

Glenn
donrandall
Posts: 550
Joined: Wed Dec 01, 2004 11:06 pm
Location: Denver, Colorado

Re: MP3 Audio "save as" options and LAME

Post by donrandall »

I was referring to your comment as shown below:
I'm still a Goldwaver, and often suggest it to others on other music forums. It still astounds me how people post waves/mp3s and the maximum level is -8dB or lower.

BTW, to what level do you max waves? I've been using -0.3dB or -0.5dB.
piano nick
Posts: 423
Joined: Wed Jun 16, 2004 8:33 pm

Re: MP3 Audio "save as" options and LAME

Post by piano nick »

Thanks Don - the light just went on.

PN
Yelnoc4
Posts: 34
Joined: Mon Apr 04, 2011 7:50 pm

Re: MP3 Audio "save as" options and LAME

Post by Yelnoc4 »

I thought I would return to this thread after again trying to save a file as MP3.

If I specify custom MP3 attributes and set VBR to any number, the resulting file always seems to be a CBR. The VBR drop-down implies to me that GW will pass this along to LAME. Apparently it only passes the bit range.

This is not really a show stopper for me as I have been using another tool for this purpose, but I thought I would mention it.
DougDbug
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Joined: Wed Feb 16, 2005 3:33 pm
Location: Silicon Valley

Re: MP3 Audio "save as" options and LAME

Post by DougDbug »

How do you know it's CBR? I assume you are working with "regular music" files?

It's working for me. When I play the files in Winamp, I see the bitrate change moment-to-moment.
The VBR drop-down implies to me that GW will pass this along to LAME. Apparently it only passes the bit range.
For me, it ignores the range. And, if you are getting a "range", that implies VBR... There is no range with CBR. And unless you have a specific reason, you should use the widest range possible and let the encoder do the "thinking".
Yelnoc4
Posts: 34
Joined: Mon Apr 04, 2011 7:50 pm

Re: MP3 Audio "save as" options and LAME

Post by Yelnoc4 »

Ok, I see something I was missing... By leaving the bit rate at the default -- 128000 to 128000 -- dbPowerAmp is naturally reporting a constant bit rate in the resulting file given that Goldwave is passing that bit range to LAME.

What I still don't understand is how the "VBR Quality" setting is used. I've become comfortable with LAME's -v settings (VBR) and my assumption is that the VBR values in the GW's drop-down are intended to match up with LAME's -v values. In other words, my assumption is that by specifying a VBR value I am overriding any values in the bit rate fields. That must not be the case.
DougDbug
Posts: 2172
Joined: Wed Feb 16, 2005 3:33 pm
Location: Silicon Valley

Re: MP3 Audio "save as" options and LAME

Post by DougDbug »

my assumption is that by specifying a VBR value I am overriding any values in the bit rate fields. That must not be the case.
If you really want an answer, you can contact Chris (GoldWave's developer) via the form on this page.

And, if you do get an answer, please let us know!

There are two LAME commands that should relate to the maximum & minimum fields in the GoldWave dialog box:
-b sets the minimum VBR bitrate (or the CBR bitrate).
-B sets the maximum VBR bitrate.
Yelnoc4
Posts: 34
Joined: Mon Apr 04, 2011 7:50 pm

Re: MP3 Audio "save as" options and LAME

Post by Yelnoc4 »

DougDbug wrote:-b sets the minimum VBR bitrate (or the CBR bitrate).
-B sets the maximum VBR bitrate.
I believe -V switch, as documented at http://wiki.hydrogenaudio.org/index.php?title=LAME, attempts to make life a little easier for the technically challenged by providing pre-sets known to be "good". It seems like the intention for the VBR drop-down being there is for passing those -V values (instead of other switch combinations). I'll see was Chris has to say.
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