Subject:Stupid bug...

Posted by: taborda

Date:6/24/2001 12:24:36 AM

In SF 5, when you save in the mp3 format, SF will create a silence in the beginning of the track. If you save it in wav format, the bug keeps sleeping, and dont annoy you. You guys, at Sonic Foundry, have a great sense of humour...eh eh.

Subject:RE: Stupid bug...

Reply by: nlamartina

Date:6/24/2001 12:58:37 AM

Taborda,

Hate to burst your bubble, but you haven't come across a bug. That 2-second silence is a mandatory part of MP3 encoding so it may conform to the international standards. If you work with any other encoder, you'll find it does the same thing. The folks at Sonic Foundry do have a sense of humor, yes, but not a sick one.

Best wishes,
Nick LaMartina

Subject:I dont believe...

Reply by: taborda

Date:6/24/2001 10:08:53 AM

Have you ever work with any other prog except SF?...
NO OTHER prog put that silence gap in tyhe beginning of the track.mp3
Don't believe? Try AUDIOACTIVE PRODUCTION STUDIO, a free, non profissional prog, and them, tell me something.
But anyway, if you say it's NORMAL (???) tell me something: If you want to record a live mix with several tracks, how do you take off the silence between the tracks?

And what is more incredible: If you cut off the silence, and save the track in .mp3, the next time you open it, the silence will be there again, and the song will be shorter, which means that if you cut silences and saves from the same track a lot of times, in the end you will have virtually no track at all.

Subject:RE: I dont believe...

Reply by: nlamartina

Date:6/24/2001 12:44:57 PM

Taborda,

As a matter of fact Tab, I have used other programs beside Sound Forge 5 for creating MP3's, such as SCMPX 1.5, Creative PlayCenter 2, CoolEdit 2k, and Adaptec CD Ripper to name a few. And you know what? Some add the 2-second silence, and others don't. I believe it has to do with what MP3 standard the programs conform to (as there are several). What version of the MP3 plugin are you using? I have version 2, and the gaps aren't appearing in my Sound Forge encoded files (either because the program overlooks them, or they're not there at all). Did you install the MP3 update? If not, do so and get back to me.

So to answer your question, yes it's normal operation. I can't give you specifics on what exactly those silences are used for, how and if programs bypass them, or if there's a standard-agnostic program out there, but I can assure you, the gaps are normal in most cases.

To answer you other question: If I'm going to record a live mix using several tracks, I will NOT use the MP3 format. First off, it's too processor intensive, which will eat up resources during recording. Secondly, it's a 16-bit format, which could substantially reduce potential quality. Third, it's a compressed format, which makes for poor navigation during editing.

And to your final question: If cutting the silences truncates your tracks, then DON'T DO IT. Okay? =) (Doctor, doctor, it hurts when I do this...)

Anyway, upgrade your MP3 plugin if possible. If I find any more relevant information concerning the format, I'll post it here, as I'd like to be a bit more knowledgable on the subject. But regardless, I hope this info helps.

Best wishes,
Nick LaMartina

Subject:RE: I dont believe...

Reply by: beetlefan

Date:6/24/2001 4:01:35 PM

I just want to add here that it's not good practice to chop off the silence right up to the sound on any type of file. A lot of people do this but perhaps this is why the sound is being truncated? I like to leave 0.8 sec at the beginning of all my misic waves. I use CE2k for mp3 and it doesn't chop off anything.

Subject:Thanks, but...

Reply by: taborda

Date:6/24/2001 7:17:18 PM

...of course i dont use mp3 compression when working on sound files. The problem is that if you want to store a live album, you have to do it in wav format (which means the same space as a audio cd), otherwise, you will not be able to record it again because of that silence gap. As you know, a live album, with all that crew, dont admit any kind of silence between tracks. The same for a live session on a disco live recording. But thanks anyway. I will look for the update.

Subject:RE: Thanks, but...

Reply by: beetlefan

Date:6/25/2001 11:13:56 AM

The following does not help you situation but I copied this from Syntrillium's forum. It specifically pertains to Cool Edit but may apply to Sound Forge as well.

--------------------------------------------------------------------------------
Hello Trevor. Cool Edit does add a bit of silence to the beginning and ending of
MP3 files. Our programmers explained to me that this was because either the 3rd party MP3 codes or Windows ACM codec we used was actually deleting about 1/5 of a second of the file when saving to MP3. So we had to add silence to the file. This way, instead of deleting the user's audio, it deleted the silence. Unfortunately, It was not always
deleting the exact amount of audio, so after some testing, we decide to add an x amount of silence to beginning and ending of audio files just before user saves it to MP3. In some cases like yours, it's about
35/100 of a second too much. But with some other files, it's just right. And as mentioned, because of the range of different encoders and decoders out there, it's a fairly common process until someone really standardizes it.


---Syntrillium Support

Subject:RE: Thanks, but...

Reply by: Ted_H

Date:6/26/2001 10:15:55 AM

Whether or not silence is added depends on the codec your mp3 encoder uses. We use the Fraunhofer codec.

Ted