#144686 - 21/02/2003 20:17
Re: Gapless playback in v2?
[Re: tfabris]
|
carpal tunnel
Registered: 25/12/2000
Posts: 16706
Loc: Raleigh, NC US
|
Okay, right now, the player can play nogapped VBR files, but they're nigh unusable because of the issues with FFing and REWing.
Hacking the support for VBR headers back into LAME for nogapped files seems to reintroduce gapping. This is because the VBR headers in LAME have been broken for quite some time (forever?). In the VBR header, there is a field that contains the number of frames in the mp3 file. LAME's frame count was always one less than what it should have been because it failed to count the VBR header itself as a frame.
The frame miscount causes some players to fail to play the final frame, apparently including the empeg player, in all its recent versions.
The specific VBR header fixer being used was also broken and dropped the final frame on the floor when ``fixing'' it, causing the same problem in a different way.
Both of these problems are compounded by the fact that 2.0b13 also seems to introduce gaps when it sees a VBR header, but Peter's build somewhere after b13 has fixed that problem, he reports.
Edit: More untruths. I've gotten so far away from the original issues, I've forgotten what they were.
Edit again: To jibe with Tony's memory, which I think is correct in this case.
Edited by wfaulk (21/02/2003 20:36)
_________________________
Bitt Faulk
|
Top
|
|
|
|
#144687 - 21/02/2003 20:24
Re: Gapless playback in v2?
[Re: wfaulk]
|
carpal tunnel
Registered: 20/12/1999
Posts: 31594
Loc: Seattle, WA
|
IIRC, even if you let lame generate nogapped VBR files without a VBR headers, you still get gaps. That's not the way I remember it being reported. My recollection is that someone reported "If I don't add the VBR headers back in, it plays fine. But the player has other problems with headerless files, so I add them in. And that's when it plays wrong." And later we found out that the reason was his header-adding tool, not the player. That's the way I recall it happening.
I could be wrong, of course. I frequently am.
|
Top
|
|
|
|
#144688 - 21/02/2003 20:29
Re: Gapless playback in v2?
[Re: tfabris]
|
carpal tunnel
Registered: 25/12/2000
Posts: 16706
Loc: Raleigh, NC US
|
Okay. I'll go with you one that one. Let me fix it again.
_________________________
Bitt Faulk
|
Top
|
|
|
|
#144689 - 21/02/2003 20:39
Re: Gapless playback in v2?
[Re: tfabris]
|
carpal tunnel
Registered: 25/12/2000
Posts: 16706
Loc: Raleigh, NC US
|
Can I send someone on the alpha team a pair of nogapped VBR mp3s and see if they can hear a gap in the current alpha build? Actually, maybe a pair or pairs, one fixed using Peter's method and one made directly by a devel version of LAME.
_________________________
Bitt Faulk
|
Top
|
|
|
|
#144692 - 23/02/2003 02:48
Re: Gapless playback in v2?
[Re: trs24]
|
carpal tunnel
Registered: 21/05/1999
Posts: 5335
Loc: Cambridge UK
|
What stage is v3 in exactly?
We'll find out after 2.0-final is released. It should be possible to release v3-alpha1 to the alpha group almost immediately, and if it seems half decent then a public beta will follow.
Rob
|
Top
|
|
|
|
#144693 - 23/02/2003 02:50
Re: Gapless playback in v2?
[Re: blitz]
|
carpal tunnel
Registered: 21/05/1999
Posts: 5335
Loc: Cambridge UK
|
A little off topic but what is the status of the bugg blatt fixes release? Is that emplode version ready to go? I desperately need USB support under XP to do a clone.
Everything is ready for RC2 except we upgraded to InstallShield 8 recently and somebody needs to convert the installer. We've been a bit busy (understatement) but hopefully we'll get to it soon.
Rob
|
Top
|
|
|
|
#144694 - 23/02/2003 07:54
Re: Gapless playback in v2?
[Re: rob]
|
carpal tunnel
Registered: 14/01/2002
Posts: 2858
Loc: Atlanta, GA
|
Hey, I just sat through an Installshield 8 training class all last week. I'll do it!
_________________________
-Jeff Rome did not create a great empire by having meetings; they did it by killing all those who opposed them.
|
Top
|
|
|
|
#144695 - 24/02/2003 01:51
Re: Gapless playback in v2?
[Re: wfaulk]
|
enthusiast
Registered: 28/03/2002
Posts: 230
Loc: Dudley, UK
|
There is another small issue that I don't think has been discussed. The "--nogap" switch itself (which was an attempt by LAME's developers to solve the "gap" issue) is not actively being supporting or developed. It is (from my reading anyways) likely to be dropped from future builds - HELP
Anyone confirm --nogap is still supported in the latest build, I'm using the one supplied with WinLAME, which works for me.
Cheers, Sim
|
Top
|
|
|
|
#144696 - 24/02/2003 08:50
Re: Gapless playback in v2?
[Re: simspos]
|
carpal tunnel
Registered: 25/12/2000
Posts: 16706
Loc: Raleigh, NC US
|
When I was talking with Mark Taylor to get the problem fixed, he didn't mention anything of the sort. Which is not to say that it's not true.
Regardless, if it works in the current version, since LAME is open source, you'll always have access to the current version. And it's not as if LAME has huge bugs left. I can't imagine what else they could add to it other than to improve the psychoacoustics further. By the time that happens significantly and nogap support has fallen by the wayside, Ogg Vorbis should be available for use on the player.
_________________________
Bitt Faulk
|
Top
|
|
|
|
#144697 - 24/02/2003 09:12
Re: Gapless playback in v2?
[Re: peter]
|
carpal tunnel
Registered: 25/12/2000
Posts: 16706
Loc: Raleigh, NC US
|
Out of curiosity, is this the reason that the VBR header inserts a gap, that the player isn't interpreting and skipping over id3 tags and VBR headers, but that something prior to that is interpreting them and telling the player to skip over them, but it's not doing it for the VBR header?
_________________________
Bitt Faulk
|
Top
|
|
|
|
#144698 - 24/02/2003 09:14
Re: Gapless playback in v2?
[Re: wfaulk]
|
old hand
Registered: 20/03/2002
Posts: 729
Loc: Palo Alto, CA
|
Does anyone know what encoder iTunes uses? I'm curious to find out. I'd imagine it's definitely not Lame. Lame as that would be.
- trs
_________________________
- trs
|
Top
|
|
|
|
#144699 - 25/02/2003 14:27
Re: Gapless playback in v2?
[Re: trs24]
|
addict
Registered: 10/11/2000
Posts: 497
Loc: Utah, USA
|
My guess would be a Fraunhofer reference encoder.
strings /Applications/iTunes/Contents/Resources/English.lproj | grep Fraun gets you "MPEG Layer-3 audio coding technology licensed from Fraunhofer IIS and THOMSON multimedia."
It's certainly possible, though, that they used some other encoder, and just paied Fraunhofer and Thomson to avoid any legal entaglement with the patent holders.
_________________________
-Aaron
|
Top
|
|
|
|
#144700 - 26/02/2003 03:36
Re: Gapless playback in v2?
[Re: adavidw]
|
carpal tunnel
Registered: 21/05/1999
Posts: 5335
Loc: Cambridge UK
|
Everyone has to pay Thompson Fraunhoffer - they own they patents, both for encoding and decoding.
Rob
|
Top
|
|
|
|
#144701 - 26/02/2003 12:30
Re: Gapless playback in v2?
[Re: rob]
|
addict
Registered: 10/11/2000
Posts: 497
Loc: Utah, USA
|
That's what I thought. Apple could conceivably use LAME in iTunes, but just because it's open source doesn't mean it would be free, as Thomson and Fraunhofer would still get their cut
_________________________
-Aaron
|
Top
|
|
|
|
#144702 - 26/02/2003 12:36
Re: Gapless playback in v2?
[Re: adavidw]
|
carpal tunnel
Registered: 30/10/2000
Posts: 4931
Loc: New Jersey, USA
|
Fraunhofer doesn't get a cut off LAME. This is the reason LAME exists and is only distributed as source code. Only when someone makes it into a binary that encodes MP3s is it 'illegal.' Apple would never be able to use LAME to encode MP3s bacuse they would be distributing it in binary form.
Remember, Lame Aint an MP3 Encoder.
_________________________
-Rob Riccardelli 80GB 16MB MK2 090000736
|
Top
|
|
|
|
#144703 - 26/02/2003 12:58
Re: Gapless playback in v2?
[Re: robricc]
|
addict
Registered: 10/11/2000
Posts: 497
Loc: Utah, USA
|
Right, that's what I'm saying
_________________________
-Aaron
|
Top
|
|
|
|
#144704 - 26/02/2003 13:12
Re: Gapless playback in v2?
[Re: robricc]
|
carpal tunnel
Registered: 25/12/2000
Posts: 16706
Loc: Raleigh, NC US
|
I don't think that that's true. The LAME site itself reports any number of commercial products that use LAME (one of them being Universal's copy protected CDs), and I doubt that either they would list them or Fraunhofer wouldn't go after them if it were ``illegal''.
All FhG wants you to do is pay money to license their patents. Once you license their patented algorithms, I doubt that they care much how you implement them. If your implementation happens to look just like the LAME implementation, then so be it.
_________________________
Bitt Faulk
|
Top
|
|
|
|
#144705 - 26/02/2003 13:16
Re: Gapless playback in v2?
[Re: wfaulk]
|
carpal tunnel
Registered: 30/10/2000
Posts: 4931
Loc: New Jersey, USA
|
OK, maybe I was talking out of my ass a little bit.
_________________________
-Rob Riccardelli 80GB 16MB MK2 090000736
|
Top
|
|
|
|
#144706 - 26/02/2003 14:16
Re: Gapless playback in v2?
[Re: wfaulk]
|
carpal tunnel
Registered: 21/05/1999
Posts: 5335
Loc: Cambridge UK
|
There are many encoders available from different companies, and those companies arel entitled to license them however they see fit. The patent fee comes into play when an encoder reaches a user - someone has to pay it. In practice this is the software vendor - i.e. empeg paid the license for each of your car players.
In theory every user of LAME should pay a fee to Thomson Fraunhoffer if nobody further up the chain has paid it on your behalf. I'm not sure if Thomson waive this as a matter of policy, or just don't bother to attempt to enforce it.
Rob
|
Top
|
|
|
|
|
|