Hi
I am currently trying to port speex v1.1.6 to a microcontroller with
very limited memory (<64Kbyte RAM).
what I found when initialising the encoder, a chunk of 32Kb was
attempted to be alloced, which failed:
src/nb_celp.c:
void *nb_encoder_init(const SpeexMode *m)
{
/* snip */
st = (EncState*)speex_alloc(sizeof(EncState)+8000*sizeof(spx_sig_t));
/* snip */
}
same goes for the decoder:
void *nb_decoder_init(const SpeexMode *m)
{
/* snip */
st = (DecState *)speex_alloc(sizeof(DecState)+4000*sizeof(spx_sig_t));
/* snip */
}
I tried to reduce the stacksize from 8000/4000 to say 2000/1000,
and reduce buffer size to 160 bytes:
src/modes.c:
/* Default mode for narrowband */
static const SpeexNBMode nb_mode = {
160, /*frameSize*/
40, /*subframeSize*/
10, /*lpcSize*/
640, /*bufSize*/ <--------- reduce to 160
this does not work, there are various crashes in strange places which
looks like its caused by stack overflow or data corruption.
question is; are there any clean way of reducing memory usage?
the stack at the end of the state object, is it only accessed
through the PUSH macros? perhaps I could write some wrappers
to use Program RAM (PRAM) instead, which is not directly accessible.
thanks.
--
Alfred E. Heggestad <alfredh@sxdesign.com>
Hi Alfred, First thing I'd like to ask is whether you're trying to achieve real-time performance, as I find it very unlikely that Speex could run in real-time on a micro-controller. Regarding bufSize, no you can't just make it the size you like. Now, it's possible to decrease the amount of memory allocated if e.g. you only use complexity 1. You can also assume that the stack is only accessed through the PUSH macro. Jean-Marc Le samedi 19 f?vrier 2005 ? 23:47 -0800, Alfred E. Heggestad a ?crit :> Hi > > I am currently trying to port speex v1.1.6 to a microcontroller with > very limited memory (<64Kbyte RAM). > > what I found when initialising the encoder, a chunk of 32Kb was > attempted to be alloced, which failed: > > src/nb_celp.c: > > void *nb_encoder_init(const SpeexMode *m) > { > /* snip */ > st = (EncState*)speex_alloc(sizeof(EncState)+8000*sizeof(spx_sig_t)); > /* snip */ > } > > > same goes for the decoder: > > void *nb_decoder_init(const SpeexMode *m) > { > /* snip */ > st = (DecState *)speex_alloc(sizeof(DecState)+4000*sizeof(spx_sig_t)); > /* snip */ > } > > I tried to reduce the stacksize from 8000/4000 to say 2000/1000, > and reduce buffer size to 160 bytes: > > > src/modes.c: > > /* Default mode for narrowband */ > static const SpeexNBMode nb_mode = { > 160, /*frameSize*/ > 40, /*subframeSize*/ > 10, /*lpcSize*/ > 640, /*bufSize*/ <--------- reduce to 160 > > > this does not work, there are various crashes in strange places which > looks like its caused by stack overflow or data corruption. > > question is; are there any clean way of reducing memory usage? > the stack at the end of the state object, is it only accessed > through the PUSH macros? perhaps I could write some wrappers > to use Program RAM (PRAM) instead, which is not directly accessible. > > > thanks. > >-- Jean-Marc Valin <Jean-Marc.Valin@USherbrooke.ca> Universit? de Sherbrooke
On Sun, 2005-02-20 at 02:54 -0500, Jean-Marc Valin wrote:> Hi Alfred, > > First thing I'd like to ask is whether you're trying to achieve > real-time performance, as I find it very unlikely that Speex could run > in real-time on a micro-controller. >well, the Ubicom IP3K is running @250 MHz@: http://www.ubicom.com/processors/ip3000-family.htm yes realtime is my goal, for ultra wideband VoIP.> Regarding bufSize, no you can't just make it the size you like. Now, > it's possible to decrease the amount of memory allocated if e.g. you > only use complexity 1. You can also assume that the stack is only > accessed through the PUSH macro. >thanks, I have managed to move the decoders PCM buffer to a different DATA segment, reducing the stack size to 4200 bytes. encoder is to follow.> Jean-Marc > > Le samedi 19 f?vrier 2005 ? 23:47 -0800, Alfred E. Heggestad a ?crit : > > Hi > > > > I am currently trying to port speex v1.1.6 to a microcontroller with > > very limited memory (<64Kbyte RAM). > > > > what I found when initialising the encoder, a chunk of 32Kb was > > attempted to be alloced, which failed: > > > > src/nb_celp.c: > > > > void *nb_encoder_init(const SpeexMode *m) > > { > > /* snip */ > > st = (EncState*)speex_alloc(sizeof(EncState)+8000*sizeof(spx_sig_t)); > > /* snip */ > > } > > > > > > same goes for the decoder: > > > > void *nb_decoder_init(const SpeexMode *m) > > { > > /* snip */ > > st = (DecState *)speex_alloc(sizeof(DecState)+4000*sizeof(spx_sig_t)); > > /* snip */ > > } > > > > I tried to reduce the stacksize from 8000/4000 to say 2000/1000, > > and reduce buffer size to 160 bytes: > > > > > > src/modes.c: > > > > /* Default mode for narrowband */ > > static const SpeexNBMode nb_mode = { > > 160, /*frameSize*/ > > 40, /*subframeSize*/ > > 10, /*lpcSize*/ > > 640, /*bufSize*/ <--------- reduce to 160 > > > > > > this does not work, there are various crashes in strange places which > > looks like its caused by stack overflow or data corruption. > > > > question is; are there any clean way of reducing memory usage? > > the stack at the end of the state object, is it only accessed > > through the PUSH macros? perhaps I could write some wrappers > > to use Program RAM (PRAM) instead, which is not directly accessible. > > > > > > thanks. > > > >-- Alfred E. Heggestad <alfredh@sxdesign.com> SX Design