[Asterisk-Users] How "expensive" are the different codecs? (Regarding CPU time)

[el Flynn]

Michael Vogel wrote:
> Thanks! That helps me a lot. Am I right that this chart is calculated 
> depending my machine's speed:

yes, the numbers will vary depending on your system load.

> 
> #######################################################################
> zhad*CLI> show translation
>          Translation times between formats (in milliseconds)
>           Source Format (Rows) Destination Format(Columns)
> 
>        G723   GSM  ULAW  ALAW  G726 ADPCM SLINR LPC10 G729A SPEEX  ILBC
>  G723     -     -     -     -     -     -     -     -     -     -     -
>   GSM     -     -    13    13    47    15    12    43     -   253   124
>  ULAW     -    41     -     1    36     4     1    32     -   242   113
>  ALAW     -    41     1     -    36     4     1    32     -   242   113
>  G726     -    82    43    43     -    45    42    73     -   283   154
> ADPCM     -    43     4     4    38     -     3    34     -   244   115
> SLINR     -    40     1     1    35     3     -    31     -   241   112
> LPC10     -    58    19    19    53    21    18     -     -   259   130
> G729A     -     -     -     -     -     -     -     -     -     -     -
> SPEEX     -    52    13    13    47    15    12    43     -     -   124
>  ILBC     -    59    20    20    54    22    19    50     -   260     -
> zhad*CLI>
> #######################################################################
> 
> Encoding to speex or ilbc seems to be too heavy for my machine ;-)
> 

hmm.. those numbers look a little... high... does it show the same values when 
your box is idle? mine gives the following, when there's no traffic going through:

demo*CLI> show translation
          Translation times between formats (in milliseconds)
           Source Format (Rows) Destination Format(Columns)

          G723   GSM  ULAW  ALAW  G726 ADPCM SLINR LPC10 G729A SPEEX  ILBC
    G723     -     -     -     -     -     -     -     -     -     -     -
     GSM     -     -     2     2     3     2     1     -     -     -     -
    ULAW     -     4     -     1     3     2     1     -     -     -     -
    ALAW     -     4     1     -     3     2     1     -     -     -     -
    G726     -     4     2     2     -     2     1     -     -     -     -
   ADPCM     -     4     2     2     3     -     1     -     -     -     -
   SLINR     -     3     1     1     2     1     -     -     -     -     -
   LPC10     -     -     -     -     -     -     -     -     -     -     -
   G729A     -     -     -     -     -     -     -     -     -     -     -
   SPEEX     -     -     -     -     -     -     -     -     -     -     -
    ILBC     -     -     -     -     -     -     -     -     -     -     -

flynn