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Lame3.99.5y, A 3.99.5 functional extension
halb27
post Mar 18 2012, 11:12
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You can download it from here.

What’s the functional extension?

It offers a VBR quality setting -V0+.

-V0+ is -V0 with extra properties. These properties can improve upon difficult-to-encode spots in the music like temporal smearing issues as with problem sample eig or with tremolo problem isues as with problem sample lead-voice. eig and lead-voice are fine to me when using -V0+.

How is it done?

-V0+ uses a strategy which is targeting at providing maximum possible audio data space for hard-to-encode spots in the music. -V0+ increases the accuracy demands for spots in the music with detected impulses, and it has a general demand for audio data bitrate to stay rather high.

What’s the price to pay?

Average bitrate goes up a little bit. For my standard test set of various pop music average bitrate is 256 kbps with -V0+, whereas -V0 takes 252 kbps.
Moreover, in order to prevent another 10 kbps increase in average bitrate, the fast and lossless mp3packer procedure is recommended to be called for the produced mp3 file. Used with a bat file invoked from the explorer’s folder context menu this is comfortably done for the mp3 files of an entire folder.
The 10 kbps bitrate bloat is a consequence of the strategy for providing maximum possible data space. For doing so a 17.5 kHz lowpass is also used internally. If you don’t like that use a lowpass according to your likings. But even if you are able to distinguish higher frequencies in an isolated listening test, this doesn’t mean you can take profit of that with real life music. Not talking about the fact that the musical contents of higher frequncies is next to nothing.

This post has been edited by halb27: Mar 18 2012, 11:37


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lame3100m -V1 --insane-factor 0.75
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halb27
post Mar 18 2012, 11:13
Post #2





Group: Members
Posts: 2424
Joined: 9-October 05
From: Dormagen, Germany
Member No.: 25015



Some remarks about ‘why a new variant after 3.99.5x was recently released?’.
I’m sorry to have to do that, and I certainly should have spent more time doing all this with 3.99.5x.

After finishing 3.99.5x I spent a lot of time with the remaining obvious issue among ‘my’ problem samples: the problem at sec. 2,82 of eig.
I ended up giving very high accuracy demands to short blocks (used when impulses are detected in the music). I also searched for improvement in providing as much data space as possible for hard-to-encode spots like impulses, and lowered a corresponding restriction (on the channels of a granule which is used for inaccurate frame handling and occasionally does not make full use of the available space in a frame. I stretched these restrictions to make full use of the available frame data space).
While doing all this I noticed that I had been focussing on avoiding inaccurately encoded frames too much. This target isn’t so important per se. It’s important to try to provide maximum available data space for difficult spots IMO, and such a strategy tends to avoid inaccurately encoded frames, but the maximum available data space is what counts in the first place.

The properties of the concern for short blocks made me reconsider what -Vx+ levels are really interesting. Lower quality levels of -Vx+ have always been questionable because using a higher quality -Vx is the more natural and more attractive alternative. With the new special concern for short blocks this is even more so: this special concern is expensive except for the highest -Vx+ levels, whereas for -Vx+ levels which internally use -V0 it comes nearly for free.

During my listening tests I became tired of testing problem samples like ‘herding_calls’. I am able to ABX them using -V0, but it is hard to do so. With practical listening without reference to the original their tiny issue would go unnoticed. I decided not to care about them any more. For tremolo problem samples like ‘trumpet_myPrince’ I optimized the minimum audio data bitrate demands in such a way that the remaining issue is similarly unimportant.

As a consequence I ended up with just one -Vx+ level, -V0+.

This post has been edited by halb27: Mar 18 2012, 11:28


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Posts in this topic
- halb27   Lame3.99.5y   Mar 18 2012, 11:12
- - halb27   Some remarks about ‘why a new variant after 3.99.5...   Mar 18 2012, 11:13
|- - GeSomeone   QUOTE (halb27 @ Mar 18 2012, 12:13) As a ...   Mar 19 2012, 00:22
- - halb27   -V0+ is now more or less what was -V1+ before, add...   Mar 19 2012, 08:08
- - ggunnell   I use dbPoweramp as a Lame front end. Currently d...   Apr 14 2012, 21:25
|- - chi   QUOTE (ggunnell @ Apr 14 2012, 22:25) …, ...   Apr 15 2012, 05:53
- - halb27   I can confirm your idea and chi's result. For ...   Apr 15 2012, 09:43
|- - ggunnell   QUOTE (halb27 @ Apr 15 2012, 03:43) I can...   Apr 15 2012, 17:15
- - halb27   So you compiled both Lame 3.99.5 and 3.99.5y yours...   Apr 15 2012, 20:20
|- - ggunnell   QUOTE (halb27 @ Apr 15 2012, 14:20) So yo...   Apr 16 2012, 05:57
- - ShotCaller   halb, seeing that -V0+ tends to be in the 300+ kbp...   Apr 16 2012, 05:40
|- - halb27   QUOTE (ShotCaller @ Apr 16 2012, 05:40) h...   Apr 16 2012, 07:31
|- - skamp   QUOTE (halb27 @ Apr 16 2012, 08:31) An op...   Apr 16 2012, 07:39
||- - halb27   QUOTE (skamp @ Apr 16 2012, 07:39) QUOTE ...   Apr 16 2012, 07:54
||- - soundping   QUOTE (skamp @ Apr 16 2012, 01:39) QUOTE ...   Apr 16 2012, 21:22
|- - GeSomeone   QUOTE (halb27 @ Apr 16 2012, 08:31) 3.99....   Apr 18 2012, 00:37
- - halb27   That's why freeformat isn't of practical u...   Apr 16 2012, 23:08
- - naturfreak   A simple question to satisfy my curioustiy: Will ...   Apr 17 2012, 14:06
- - halb27   I welcome this, but it's up to the Lame devs.   Apr 17 2012, 19:28
- - halb27   Using a higher lowpass frequency has an effect on ...   Apr 18 2012, 00:50
|- - IgorC   QUOTE (halb27 @ Apr 17 2012, 20:50) Main ...   Apr 18 2012, 02:53
- - halb27   Big trouble! I managed to put a premature ver...   Sep 8 2012, 19:46
- - goa pride   QUOTE (halb27 @ Sep 8 2012, 19:46) Big tr...   Sep 9 2012, 21:37
- - Dynamic   QUOTE (goa pride @ Sep 9 2012, 21:37) is ...   Sep 9 2012, 22:37
|- - Dynamic   QUOTE (Dynamic @ Sep 9 2012, 22:37) Come ...   Sep 10 2012, 17:57
- - halb27   QUOTE (goa pride @ Sep 9 2012, 22:37) is ...   Sep 9 2012, 23:29


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