[MP3 ENCODER] Fwd: stereo audio compression quality

[Alexander Leidinger]

Hi,

please CC him in the reply.

Bye,
Alexander.

------ Forwarded message ------
              Von: Gregory Abbey <[EMAIL PROTECTED]>
          Betreff: stereo audio compression quality
            Datum: Thu, 03 Jan 2002 13:17:57 -0500
               An: [EMAIL PROTECTED]
         X-Mailer: QUALCOMM Windows Eudora Version 5.1
       Message-ID: <[EMAIL PROTECTED]>


Hello..

I have been running experiments encoding 44khz PCM stereo .wav files into 
MP3's.

have used the following encoders:  Blade_dll, and  Lame_dll.


Question:

Process runs smoothly except there are numerous low level pops, thumps, and 
other discontinuous sounds on playback.  What is the cause of these 
discontinuities?

      a)  encoding algorithm

      b)  playback hardware, i.e. soundboard, IRQ conflict, etc.



Typical data:

Input file:   24118 KB .wav  stereo

256kbps   Blade 0.94     5.5x     0:32 sec     4376 KB     Playback: 256k
256kbps   Blade 0.91     5.5x     1:26 sec     4376 KB      256k

256k hi    Lame 3.90     5.5x     0:31 sec     4378 KB       256k

128k hi    Lame ABR    11.0x    0:35 sec     2184 KB       127k ave
160k hi    Lame ABR     8.8x     0:33 sec     2734 KB       159k ave
192k hi    Lame ABR     7.4x     0:32 sec     3278 KB       191k ave

2-new hi  Lame VBR      8.0x     0:31 sec     3001 KB       175k ave
1-new hi  Lame VBR      7.7x     0:32 sec     3135 KB       183k ave
0-new hi  Lame VBR      7.2x     0:32 sec     3366 KB       196k ave

0-old hi    Lame VBR      7.4x     1:09 sec     3263 KB       190k ave

Hello..

I have been running experiments encoding 44khz PCM stereo .wav files into MP3's.

have used the following encoders:  Blade_dll, and  Lame_dll.


Question:

Process runs smoothly except there are numerous low level pops, thumps, and other discontinuous sounds on playback.  What is the cause of these discontinuities?

     a)  encoding algorithm

     b)  playback hardware, i.e. soundboard, IRQ conflict, etc.



Typical data:

Input file:  24118 KB .wav  stereo

256kbps   Blade 0.94     5.5x     0:32 sec     4376 KB     Playback: 256k
256kbps   Blade 0.91     5.5x     1:26 sec     4376 KB      256k    

256k hi    Lame 3.90     5.5x     0:31 sec     4378 KB       256k

128k hi    Lame ABR    11.0x    0:35 sec     2184 KB       127k ave
160k hi    Lame ABR     8.8x     0:33 sec     2734 KB       159k ave
192k hi    Lame ABR     7.4x     0:32 sec     3278 KB       191k ave

2-new hi  Lame VBR      8.0x     0:31 sec     3001 KB       175k ave
1-new hi  Lame VBR      7.7x     0:32 sec     3135 KB       183k ave
0-new hi  Lame VBR      7.2x     0:32 sec     3366 KB       196k ave

0-old hi    Lame VBR      7.4x     1:09 sec     3263 KB       190k ave