You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
133 lines
3.9 KiB
133 lines
3.9 KiB
/*
|
|
The mediastreamer library aims at providing modular media processing and I/O
|
|
for linphone, but also for any telephony application.
|
|
Copyright (C) 2001 Simon MORLAT simon.morlat@linphone.org
|
|
|
|
This library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
This library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with this library; if not, write to the Free Software
|
|
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
|
|
#include <msAlawdec.h>
|
|
#include <g711common.h>
|
|
|
|
extern MSFilter * ms_ALAWencoder_new(void);
|
|
|
|
MSCodecInfo ALAWinfo={
|
|
{
|
|
"ALAW codec",
|
|
0,
|
|
MS_FILTER_AUDIO_CODEC,
|
|
ms_ALAWencoder_new,
|
|
"This is the classic A-law codec. Good quality, but only usable with high speed network connections."
|
|
},
|
|
ms_ALAWencoder_new,
|
|
ms_ALAWdecoder_new,
|
|
320,
|
|
160,
|
|
64000,
|
|
8000,
|
|
8,
|
|
"PCMA",
|
|
1,
|
|
1,
|
|
};
|
|
|
|
static MSALAWDecoderClass *ms_ALAWdecoder_class=NULL;
|
|
|
|
MSFilter * ms_ALAWdecoder_new(void)
|
|
{
|
|
MSALAWDecoder *r;
|
|
|
|
r=g_new(MSALAWDecoder,1);
|
|
ms_ALAWdecoder_init(r);
|
|
if (ms_ALAWdecoder_class==NULL)
|
|
{
|
|
ms_ALAWdecoder_class=g_new(MSALAWDecoderClass,1);
|
|
ms_ALAWdecoder_class_init(ms_ALAWdecoder_class);
|
|
}
|
|
MS_FILTER(r)->klass=MS_FILTER_CLASS(ms_ALAWdecoder_class);
|
|
return(MS_FILTER(r));
|
|
}
|
|
|
|
|
|
/* FOR INTERNAL USE*/
|
|
void ms_ALAWdecoder_init(MSALAWDecoder *r)
|
|
{
|
|
ms_filter_init(MS_FILTER(r));
|
|
MS_FILTER(r)->infifos=r->f_inputs;
|
|
MS_FILTER(r)->outfifos=r->f_outputs;
|
|
MS_FILTER(r)->r_mingran=ALAW_DECODER_RMAXGRAN;
|
|
memset(r->f_inputs,0,sizeof(MSFifo*)*MSALAWDECODER_MAX_INPUTS);
|
|
memset(r->f_outputs,0,sizeof(MSFifo*)*MSALAWDECODER_MAX_INPUTS);
|
|
|
|
}
|
|
|
|
void ms_ALAWdecoder_class_init(MSALAWDecoderClass *klass)
|
|
{
|
|
ms_filter_class_init(MS_FILTER_CLASS(klass));
|
|
ms_filter_class_set_name(MS_FILTER_CLASS(klass),"ALAWDecoder");
|
|
MS_FILTER_CLASS(klass)->info=(MSFilterInfo*)&ALAWinfo;
|
|
MS_FILTER_CLASS(klass)->max_finputs=MSALAWDECODER_MAX_INPUTS;
|
|
MS_FILTER_CLASS(klass)->max_foutputs=MSALAWDECODER_MAX_INPUTS;
|
|
MS_FILTER_CLASS(klass)->r_maxgran=ALAW_DECODER_RMAXGRAN;
|
|
MS_FILTER_CLASS(klass)->w_maxgran=ALAW_DECODER_WMAXGRAN;
|
|
MS_FILTER_CLASS(klass)->destroy=(MSFilterDestroyFunc)ms_ALAWdecoder_destroy;
|
|
MS_FILTER_CLASS(klass)->process=(MSFilterProcessFunc)ms_ALAWdecoder_process;
|
|
}
|
|
|
|
void ms_ALAWdecoder_process(MSALAWDecoder *r)
|
|
{
|
|
MSFifo *fi,*fo;
|
|
int inlen,outlen;
|
|
gchar *s,*d;
|
|
int i;
|
|
/* process output fifos, but there is only one for this class of filter*/
|
|
|
|
/* this is the simplest process function design:
|
|
the filter declares a r_mingran of ALAW_DECODER_RMAXGRAN, so the mediastreamer's
|
|
scheduler will call the process function each time there is ALAW_DECODER_RMAXGRAN
|
|
bytes to read in the input fifo. If there is more, then it will call it several
|
|
time in order to the fifo to be completetly processed.
|
|
This is very simple, but not very efficient because of the multiple call function
|
|
of MSFilterProcessFunc that may happen.
|
|
The MSAlawEncoder implements another design; see it.
|
|
*/
|
|
|
|
fi=r->f_inputs[0];
|
|
fo=r->f_outputs[0];
|
|
g_return_if_fail(fi!=NULL);
|
|
g_return_if_fail(fo!=NULL);
|
|
|
|
inlen=ms_fifo_get_read_ptr(fi,ALAW_DECODER_RMAXGRAN,(void**)&s);
|
|
if (s==NULL) return;
|
|
outlen=ms_fifo_get_write_ptr(fo,ALAW_DECODER_WMAXGRAN,(void**)&d);
|
|
if (d!=NULL)
|
|
{
|
|
for(i=0;i<ALAW_DECODER_RMAXGRAN;i++)
|
|
{
|
|
((gint16*)d)[i]=alaw_to_s16( (unsigned char) s[i]);
|
|
}
|
|
}
|
|
else g_warning("MSALAWDecoder: Discarding samples !!");
|
|
|
|
}
|
|
|
|
|
|
|
|
void ms_ALAWdecoder_destroy( MSALAWDecoder *obj)
|
|
{
|
|
g_free(obj);
|
|
}
|