[Speex-dev] How can I minimize the memory usage of speex?

Jean-Marc Valin jean-marc.valin at usherbrooke.ca
Wed Sep 26 02:52:46 PDT 2007

I guess the first thing to say is that the 6 kB figure assumes that all
the constant stuff (code and static tables) need to be in ROM. From
there, you need to build with VAR_ARRAYS defined or else play with the
values of NB_ENC_STACK and NB_DEC_STACK.


Sevan Haritounian wrote:
> Hi,
> I am trying to implement Speex in freeRtos on LPC2138 (ARM7 core), to record about 10sec of voice. I like to compress the data by using Speex, because of the limitation of RAM (32KB). I have read that the speex encoder and decoder need less than 6KB RAM.
>  "The fixed-point narrowband encoder+decoder memory use has been cut by more than half, making it possible to fit both in less than 6 kB of RAM".
> It seems to work, but my implementation needs a lot more RAM. Now my questions: How do I have to configure the en-decoder (I already set the complexity to 1) and which libraries are minimum required?  
> Best regards
> Sevan

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