[MP3 ENCODER] free MP1 or MP2 encoders - give me please url

2000-09-10 Thread RAM

Hi Jaroslav!
You wrote, that you use mp1 or mp2 encoders for best quality  results.
Are they free or not?
Give me please - where did you take it? Give please some url.

Alexander
Russia


- Original Message -
From: Jaroslav Lukesh [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Sent: Wednesday, September 06, 2000 5:17 PM
Subject: Re: [MP3 ENCODER] mpglib compiles once again...


 |  Is there a simple Layer I coder out there to test Layer I decoding?
 |  I've never have seen a Layer I file.
 |
 | Isn't there some ISO Layer I test bitstreams? In the negative case,
Layer
 I

 If you want to send some short sample to test decoder, send me mail.

 layer 1 is absolutely BEST lossy audio (by me).

 If you want to use very high bitrates such as 320, 384 kb, use layer1. If
 you want to use 192..320kb bitrates, use layer 2 and at low bitrates up to
 160k use layer3. All encoders have different characteristic of unwanted
 effects, but layer1 is my favourite for audio archival.

 Regards

  Jaroslav Lukesh
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Re: [MP3 ENCODER] very lowand very high-quality settings

2000-09-10 Thread Heribert Maier

Thank you Mark,

for your suggestions and explanations!
I will test the different hints from various persons on a DDD recording
and then I can pass to my old mono sound files.

Regarding the second question (CBR 256 versus VBR) I finally
understood what is going on. For now I will stick to the cbr 256
basically because it appears that the bitreservoir stores the extra
info for "difficult frames" beyond the 256-mark.

And last but not least I will do an "-mm -b128" on all my pre-1960
recordings optaining the same quality as with "-ms -b256" on those
mono files. 50% is an amazing save in space...:-)

Bye,

Heribert.

Mark Taylor writes:
  

   
   -V4 -mm -h -b24 -q1 --resample 22.05
  

  Before you settle on this, do some comparisons with CBR.
  I would reccomend:
  
  % lame -h -b 32 --resample 22.05  
  
  And then try playing with --lowpass X, with x ranging from 3 to 10.  
  (the CBR default filterlevel may not be correct for low bitrate encodings).
  Once you get the best CBR results with the target bitrate, 
  then compare with the VBR stuff and other exotic options
  to see if they are any better.
  
  
   
   Second question: is it possible to obtain better quality then
   "-h -ms -b256" with some vbr-mode. Maybe I am far off, but if I
   encode with vbr and there are 320kbps-frames these parts should be
   encoded better than in cbr-256-mode. Am I wrong?
  
  No, at those bitrates there is no reason to use VBR.  CBR,
  because of the bitreservoir, is also really a limited form of VBR
  which small fluctations in bitrate and the occastional large jump.
  cbr-256 will fluctuate between using the same number of bits
  as in a 220-320kbs just as effectively as VBR.  
  
  
   I tweaked a little but usually it is almost impossible with vbr to get
   an abr200kbps. (Nonsense-settings as vbr -b 256 apart. They result often
   in a cbr 256)
   Why? I would prefer an abr 256-file if it sounds better then the cbr
   256-file, of course.
   
  
  Can VBR and/or ABR get 256kbs results at a lower bitrate?
  I wish I knew :-)
  
  Mark
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Re: [MP3 ENCODER] Re: MP3 Format

2000-09-10 Thread Frank Klemm

Presets:

There are three blocks which can be selected via conditional compiling.

Block 2: use low fs
Block 3: do not use fsb21 if possible.

Differences are:
Block 2 Block
phon+ (0...4 kHz)   fs=8 kHzfs=11 kHz
700 KB  610 KB

voice (0...12 kHz)  fs=24 kHz   fs=32 kHz
1.8 MB  2.0 MB

So I suggest to use block 1, which uses the fs with the lowest bitrate.

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[MP3 ENCODER] VBR / CBR / ABR

2000-09-10 Thread Frank Klemm

CBR VBR ABR

Can use different frame sizes   no  yes yes

File size depends also on   
  complexity of source  no  yes no

Can adapted bit demand by
  * different frame sizes   no  yes yes
  * use of bits from the pool   yes ?   no

Size of the bit pool (bit)  
  * MPEG-1:  4088   ?   ?
  * MPEG-2:  2040   ?   ?

frame size for 320 kbps/
  32   kHz (bit)11520   11520   11520
  44.1 kHz (bit) 836083608360
  48   kHz (bit) 768076807680

effective framesize 
  regarding the usage of the
  bitpool (bit) 
  * ISO:61440   ?   ?
  * common usage:  131072   ?   ?

Size of the original PCM 
  data (2*16 bit)   36864   36864   36864


What would be done in VBR/ABR if the needed frame size is between two
allowed sizes? Emitting frames with wobbling effective frame size or also
using a (small) bit pool and a more constant effective frame size?

-- 
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Re: [MP3 ENCODER] very lowand very high-quality settings

2000-09-10 Thread Robert Hegemann

Frank Klemm schrieb am Son, 10 Sep 2000:
 ::   
 ::   Second question: is it possible to obtain better quality then
 ::   "-h -ms -b256" with some vbr-mode. Maybe I am far off, but if I
 ::   encode with vbr and there are 320kbps-frames these parts should be
 ::   encoded better than in cbr-256-mode. Am I wrong?
 ::  
 ::  No, at those bitrates there is no reason to use VBR.  CBR,
 ::  because of the bitreservoir, is also really a limited form of VBR
 ::  which small fluctations in bitrate and the occastional large jump.
 ::  cbr-256 will fluctuate between using the same number of bits
 ::  as in a 220-320kbs just as effectively as VBR.  
 ::  
 What are the differences between:
 
-h -ms -b256
-h -ms -b256 -V0 -F
 
 or more often used:
 
-h -ms -b192
-h -ms -b192 -V0 -F
 
 I thought the "-V0" versions are better. The coder has the ability to
 increase bit rate on demand. There are only problems with the so called
 silence detection which generates switching artefacts, so I added the -F
 option. 


I thought we already had a -F option
It strictly enforces to use the minimum bitrate in VBR mode.


 For very low audio levels I would prefer a adaptive low pass filter
 and adaptive data rate. May be this will be added if sample_t becomes float.
 
 Level (1...5 kHz) Lowpass (kHz)   Channel Datarate
   separation
  -30 dB   24 kHz1.0   min (b, 320)
  -40 dB   20 kHz1.0   min (b, 256)
  -50 dB   18 kHz1.0   min (b, 192)
  -60 dB   16 kHz1.0   min (b, 128)
  -70 dB   12 kHz0.99  min (b, 112)
  -80 dB7 kHz0.9   min (b,  96)
  -90 dB4 kHz0.5   min (b,  48)
 -100 dB3 kHz0.1   32
 -110 dB2 kHz0.01  32
 
 -- 
 Mit freundlichen Grüßen
 Frank Klemm
  
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Ciao Robert


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Re: [MP3 ENCODER] VBR / CBR / ABR

2000-09-10 Thread Robert Hegemann

Frank Klemm schrieb am Son, 10 Sep 2000:
 CBR   VBR ABR
 
 Can use different frame sizes no  yes yes
 
 File size depends also on 
   complexity of sourceno  yes no
 
 Can adapted bit demand by
   * different frame sizes no  yes yes
   * use of bits from the pool yes ?   no

 yes yes yes

 
 Size of the bit pool (bit)
   * MPEG-1:4088   ?   ?
   * MPEG-2:2040   ?   ?

4088 4088 4088
2040 2040 2040

 frame size for 320 kbps/
   32   kHz (bit)  11520   11520   11520
   44.1 kHz (bit)   836083608360
   48   kHz (bit)   768076807680

another constraint:
each granule has to be less than 4096 bits

 effective framesize   
   regarding the usage of the  
   bitpool (bit)   
   * ISO:  61440   ?   ?
   * common usage:131072   ?   ?
 
 Size of the original PCM 
   data (2*16 bit) 36864   36864   36864
 
 
 What would be done in VBR/ABR if the needed frame size is between two
 allowed sizes? Emitting frames with wobbling effective frame size or also
 using a (small) bit pool and a more constant effective frame size?

could lead to wasted bits

 -- 
 Mit freundlichen Grüßen
 Frank Klemm
  
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Ciao Robert


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[MP3 ENCODER] MS switching

2000-09-10 Thread Frank Klemm

Currently there are the following options to control
channel frame coding:

-ms only LR frames allowed
-mf only MS frames allowed
-mj both are allowed

But there are no controls to affect the switching more sensitively.

So, for instance, a switch can be added to set a penalty bitrate for
the MS coding theme:

-mS  10  use MS coding if it saves 10 kbps
-mS  20  use MS coding if it saves 20 kbps
-mS 200  use always LR coding scheme 

Also the threshold can be adjusted due to the average bitrate.

   -q1-q2-q5-q7
 96 uses -mS   3   uses -mS   3   uses -mS   3   uses -mS   3
112 uses -mS   6   uses -mS   6   uses -mS   6   uses -mS   6
128 uses -mS  10   uses -mS  10   uses -mS  10   uses -mS  10
144 uses -mS  15   uses -mS  15   uses -mS  15   uses -mS 200
160 uses -mS  20   uses -mS  20   uses -mS 200   uses -mS 200
192 uses -mS  30   uses -mS 200   uses -mS 200   uses -mS 200
224 uses -mS  40   uses -mS 200   uses -mS 200   uses -mS 200
256 uses -mS  50   uses -mS 200   uses -mS 200   uses -mS 200
320 uses -mS 200   uses -mS 200   uses -mS 200   uses -mS 200

So the usage of the MS frames becomes more and more unlikely for high
bitrates.
This is better than a sharp break.

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[MP3 ENCODER] Extending report

2000-09-10 Thread Frank Klemm

Is it possible to extend the report at the end?


128.0 kbps  frames: 1 total,  571 short,  8917 Mid/Side

"%5.1f kbps\tframes: %5lu total, %4lu short, %5lu Mid/Side\n"

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[MP3 ENCODER] libmp3lame shared library?

2000-09-10 Thread Erik Gustavsson

Hi!

This may be semi-offtopic because its more like a general Unix/Linux
question...  How can I compile libmp3lame as a shared library
(libmp3lame.so) ??   Can this be added as an alternative target in the
Makefile perhaps? Or even made the default for Linux?  Is there a reason
for *not* using shared libs?

/cyr

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[MP3 ENCODER] changes to version.c

2000-09-10 Thread Joshua Bahnsen

#include "sndfile.h"

should be added to version.c on or around line 25, sf_get_lib_version is
undefined otherwise. Of course it only makes a difference if you use
libsndfile, but it caused me a problem.

Joshua Bahnsen
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Re: [MP3 ENCODER] MS switching

2000-09-10 Thread Roel VdB

Hello Frank,

Sunday, September 10, 2000, 6:39:22 PM, you wrote:
FK But there are no controls to affect the switching more sensitively.
FK So, for instance, a switch can be added to set a penalty bitrate for
FK the MS coding theme:
FK -mS  10  use MS coding if it saves 10 kbps
FK -mS  20  use MS coding if it saves 20 kbps
FK -mS 200  use always LR coding scheme 

this is just what I was afraid of: fighting symptoms instead of
a fundamental change. (-mx thread)

what is the use of sacrificing kbits in trade for assumed quality
gains?  There will always be pieces where even -mS 100 will not be
enough, and you loose a lot of the use of JS.

An algorhytm needs to be adaptive: you put in music, and what comes
out should be the best possible: M/S or LR.  If it takes encoding all
double and measuring distortion or so, it takes encoding all double.
I'd still prefer it than a patched-up fundamentally inept model.  With
all these settings, won't you loose a great deal of universality?

Why not look more at JS (-mx) as a sort of variable switching algorhytm
, like vbr-old iirc, rather than a, becoming increasingly complex,
condition to switch to MS.

Adding -mS xx will weaken the benefits of JS (saving space), and what
is there to gain?  A hack for some music pieces, while you're even
further off shore since you're left a less powerfull algo with still
no form of assuring quality.

just my 2c, not trying to stop a creative process, but simply giving
my reflection on this.

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Re: [MP3 ENCODER] changes to version.c

2000-09-10 Thread Sigbjørn Skjæret

#include "sndfile.h"
should be added to version.c on or around line 25, sf_get_lib_version is
undefined otherwise. Of course it only makes a difference if you use
libsndfile, but it caused me a problem.

Actually, I just fixed that, and the correct solution is to include
get_audio.h which in turn includes sndfile.h .. the reason for this is that
there's a special alignment for WIN32 apparently.


- CISC

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Re: [MP3 ENCODER] very lowand very high-quality settings

2000-09-10 Thread Frank Klemm

::  
::   I thought the "-V0" versions are better. The coder has the ability to
::   increase bit rate on demand. There are only problems with the so called
::   silence detection which generates switching artefacts, so I added the -F
::   option.
::  
::  Using -V0 the ATH is lowered (by 16 dB I think), so there are a lot less
::  analog silences than in cbr mode.
::  But could you explain why analog silence (and then switching to low bitrate
::  frames) could lead to switching artefacts? And did you ever encountered such
::  an artefact cause by analog silence processing?
::  

A)
Take a EBU test CD for low voltage converter linearity (for instance used by
"Stiftung Warentest" to test CD players).
It contains some music attenuated by 60 dB.

Or take some WAV files with fade ins and fade outs and attenuated this by 
60 dB (Dire Straits: Brothers in Arms, Private Investigations).

B)
Code this files by lame with

  lame -V0 -b160 -q1  input-60.wav output.0.mp3
  lame -V4 -b160 -q1  input-60.wav output.4.mp3
  lame -b160 -q1  input-60.wav output.c.mp3
  lame -b160 -q1 -mm  input-60.wav output.m.mp3

C)
Enforce input.wav, output.0.mp3, output.4.mp3, output.c.mp3
and output.m.mp3 by 54 dB.

D)
Listen to this 5 enforced sound files.

output.+54.wav: noisy, no artefacts
output.c.+54.mp3:   noisy, no artefacts
output.m.+54.mp3:   much more noisy, no artefacts

output.4.+54.mp3:   heaviest MP3 artefacts, combined with a lot of random muting
bitrate: 0:00-0:04   32 kbps (muted)
 0:02-6:36  160 kbps (with some mutes)
 6:36-7:00   32 kbps (muted)

output.0.+54.mp3:   heavy MP3 artefacts, combined with random muting
bitrate: 0:00-0:01   32 kbps (muted)
 0:02-6:36  160 kbps
 6:57-7:00   32 kbps (muted)


Okay, this is not normal operation. But it's a test to show weakness
of the coder.

Tools available to HQ-attenuate WAV files and enforce MP3 files.


::  For very low audio levels I would prefer a adaptive low pass filter
::   and adaptive data rate. May be this will be added if sample_t becomes
::  float.
::  
::   Level (1...5 kHz) Lowpass (kHz) Channel Datarate
::   separation
::-30 dB 24 kHz   1.0 min (b, 320)
::-40 dB 20 kHz   1.0 min (b, 256)
::-50 dB 18 kHz   1.0 min (b, 192)
::-60 dB 16 kHz   1.0 min (b, 128)
::-70 dB 12 kHz   0.99 min (b, 112)
::-80 dB 7 kHz   0.9 min (b,  96)
::-90 dB 4 kHz   0.5 min (b,  48)
::   -100 dB 3 kHz0.1 32
::   -110 dB 2 kHz 0.01 32
::  
::  Wouldn't this lead to some artefacts due to the change of available
::  frequencies? 
::
It will sounds a little bit muffled. But recodings without lots of
distortions in this level region will have a lot of shaping noise in this
range, so the Encoder is confused by this noise.


::  And if it's not the case, why only lowpassing and not bandpassing?
::  
Bandpassing is better, indeed. If available.

-- 
Mit freundlichen Grüßen
Frank Klemm
 
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[MP3 ENCODER] LAME style guide, rule #1

2000-09-10 Thread Mark Taylor


 
 I'm not too fond of your new naming-scheme for defines to check if a include
 has already been included (__VERSION_H__ f.ex.)...
 
 Generally this scheme is only for internal compiler defines and system
 includes, and normal projects should not use pre- and postceding underscores
 in defines (esp. not two).
 
 The old scheme is the more publically excepted method (VERSION_H_INCLUDED).
 
 
 - CISC
 

I dont know what is the "correct" convention, and I put these types
of changes under the catagory of cosmetic.  I personally do not care
what is used, but I do care if they are changed for no good reason!

Changing them makes life very difficult for people (like myself) who
try to keep up with *important* changes.  When the MP3 output has
changed, it is usefull to track down why it has changed, and thus code
changes (which do not represent bug fixes or additional functionality)
should be kept to a minimum.

Yes it is true that LAME does not have a good coding style.  This is
because it has evolved from dist10.tar.gz, and many developers work on
it.  LAME is not a computer science project: it is a production code
for which mp3 quality is the number 1 concern, and tracking changes
which effect quality is my number 1 concern.


Thus, here is a first draft of the the first rule for the official 
LAME Sytle guide:

1. COSMETIC CHANGES 

If you didn't write a routine, dont change the style, indentation,
tabs, variable names, function names, #ifdef names, capitalization,
spacing between lines, spacing between commas, spacing between
operaters, etc etc etc, unless you have a good reason.


Here are some examples:

good reasons:
1. Mac cant handle local arrays  32kb.  
2. The variable named 'stereo' is used in a confusing way.
3. Adding or elaborating on comments

bad reasons:
1. code does not compile under g++
2. code not in your prefered style.


LAME compiles on all modern OS's, and under dozens of C compilers.
This fact alone means that LAME is effectively complient C code.  No
additional "complience" work is needed or wanted.  If you disagree, start a
discussion in mp3encoder and try to convience other developers.





















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Re: [MP3 ENCODER] include-defines

2000-09-10 Thread Frank Klemm

::  I'm not too fond of your new naming-scheme for defines to check if a include
::  has already been included (__VERSION_H__ f.ex.)...
::  
::  Generally this scheme is only for internal compiler defines and system
::  includes, and normal projects should not use pre- and postceding underscores
::  in defines (esp. not two).
::  
::  The old scheme is the more publically excepted method (VERSION_H_INCLUDED).
::  
These tokens should be similar.

A file has the name:

path/name.extention

Currently in usage:

1   __name_extention__
2   name_extention
3   name_extention_INCLUDED
4   name_extention_INCLUDE
5   name_DOT_extention
6   somethingelse_H

Select one and apply it to ALL files. 3) seems to be a good joice.
Someone against this?

-- 
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Re: [MP3 ENCODER] LAME style guide, rule #1

2000-09-10 Thread Frank Klemm

On Sun, Sep 10, 2000 at 05:23:32PM -0600, Mark Taylor wrote:
 
 LAME compiles on all modern OS's, and under dozens of C compilers.
 This fact alone means that LAME is effectively complient C code.  No
 additional "complience" work is needed or wanted.  If you disagree, start a
 discussion in mp3encoder and try to convience other developers.
 
I've tested serveral DSP boards (32 bit, lame has several 16 bit flaws, so
16 bit will never work) and the code doesn't works on any
of them. You can compile the code without any problem, the program also
runs, but the output have nothing to do with MP3.

Okay, C is a language "guarantee for nothing, compile everything", so it's
very difficult to write something which is "complient C code".

Yesterday I compiled "The old man and the sea", got only 3 warnings, but the
program does not run. Strange ;-)

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Re: [MP3 ENCODER] libmp3lame shared library?

2000-09-10 Thread Benjamin Reed

 same shared library.  Is this libmp3lame library really of use
 to any program other than lame?

Most definitely!  I've got a perl program called "DJ In A Box" that does
on-the-fly shoutcast streaming using the lame command line, and we're in the
process of trying to make a perl module using libmp3lame.  Unfortunately,
there's a lot of stuff right now that's kind of funky to have in a library
(printing status info to stderr).  The guy doing it is running into some
problems with one of the libmp3lame functions closing filehandles it didn't
open (I believe in the encode wrapper function, I'm not much of a C guy so I
can't elaborate), but other than that and the cosmetic stuff, it looks like
it will work just fine.

I just thought I'd chime in with a "yes"!  :)

--
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http://defiance.dyndns.org/ / http://radio.scenespot.org/
Now playing on Defiance Radio: Spacefunk by Digital


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Re: [MP3 ENCODER] MS switching

2000-09-10 Thread Mark Taylor

 
 Have someone measured the coding delay for FhG and lame ???
 How many PCM samples must be feeded to achieve the first MP3 frame?
 
 May be FhG have a longer delay to see more of it's "future"?
 

mp3enc3.1 high quality (default):  encoding delay 1160
For other modes it is slightly different.

LAME:  576  (but you can set this to any value = 48 in encoder.h)

Note that most decoders have an additional delay of 573,
so be sure to add that.  

lame --decode will remove the first 576+573 samples when decoding.



Mark





  
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Re: [MP3 ENCODER] VBR / CBR / ABR

2000-09-10 Thread Mark Taylor

 
   CBR VBR ABR
 
 Can use different frame sizes no  yes yes
 
 File size depends also on 
   complexity of sourceno  yes no
 

CBR and ABR adjust bits based on the PE.  VBR adjusts the bits
based on the quantization noise.  So both depend on the complexity
of the source material.



 Can adapted bit demand by
   * different frame sizes no  yes yes
   * use of bits from the pool yes ?   no
 

VBR and ABR use bits from the bit reservoir, but the
reservoir is intentionally kept as small as possible.
With VBR and ABR, there is no reason to try to build
up a large reservoir.  


 
 What would be done in VBR/ABR if the needed frame size is between two
 allowed sizes? Emitting frames with wobbling effective frame size or also
 using a (small) bit pool and a more constant effective frame size?
 

VBR/ABR would have to use the larger size.  The unused bits
are added to the reservoir, so for the next frame it may
use the smaller frame size + reservoir, and so the
bitrate will wobble as you suggest.

VBR/ABR only uses the reservoir to avoid wasting bits,
since the number of bits needed is never exactly equal
to the number available.

Mark
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