int speex_inband_handler(SpeexBits *bits, SpeexCallback *callback_list, void *state)
{
int id;
SpeexCallback *callback;
/*speex_bits_advance(bits, 5);*/
id=speex_bits_unpack_unsigned(bits, 4);
callback = callback_list+id;
if (callback->func)
{
return callback->func(bits, state, callback->data);
} else
/*If callback is not registered, skip the right number of bits*/
{
int adv;
if (id<2)
adv = 1;
else if (id<8)
adv = 4;
else if (id<10)
adv = 8;
else if (id<12)
adv = 16;
else if (id<14)
adv = 32;
else
adv = 64;
speex_bits_advance(bits, adv);
}
return 0;
}
/*
* Decode frame.
*/
static pj_status_t spx_codec_decode( pjmedia_codec *codec,
const struct pjmedia_frame *input,
unsigned output_buf_len,
struct pjmedia_frame *output)
{
struct spx_private *spx;
unsigned samples_per_frame;
spx = (struct spx_private*) codec->codec_data;
samples_per_frame=spx_factory.speex_param[spx->param_id].samples_per_frame;
PJ_ASSERT_RETURN(output_buf_len >= samples_per_frame << 1,
PJMEDIA_CODEC_EPCMTOOSHORT);
if (input->type != PJMEDIA_FRAME_TYPE_AUDIO) {
pjmedia_zero_samples((pj_int16_t*)output->buf, samples_per_frame);
output->size = samples_per_frame << 1;
output->timestamp.u64 = input->timestamp.u64;
output->type = PJMEDIA_FRAME_TYPE_AUDIO;
return PJ_SUCCESS;
}
/* Copy the data into the bit-stream struct */
speex_bits_read_from(&spx->dec_bits, (char*)input->buf, (int)input->size);
/* Set Speex dec_bits pointer to the start bit of the frame */
speex_bits_advance(&spx->dec_bits, input->bit_info);
/* Decode the data */
speex_decode_int(spx->dec, &spx->dec_bits, (spx_int16_t*)output->buf);
output->type = PJMEDIA_FRAME_TYPE_AUDIO;
output->size = samples_per_frame << 1;
output->timestamp.u64 = input->timestamp.u64;
return PJ_SUCCESS;
}
/* This function will iterate frames & submodes in the Speex bits.
* Returns 0 if a frame found, otherwise returns -1.
*/
int speex_get_next_frame(SpeexBits *bits)
{
static const int inband_skip_table[NB_SUBMODES] =
{1, 1, 4, 4, 4, 4, 4, 4, 8, 8, 16, 16, 32, 32, 64, 64 };
static const int wb_skip_table[SB_SUBMODES] =
{SB_SUBMODE_BITS+1, 36, 112, 192, 352, -1, -1, -1};
unsigned submode;
unsigned nb_count = 0;
while (speex_bits_remaining(bits) >= 5) {
unsigned wb_count = 0;
unsigned bit_ptr = bits->bitPtr;
unsigned char_ptr = bits->charPtr;
/* WB frame */
while ((speex_bits_remaining(bits) >= 4)
&& speex_bits_unpack_unsigned(bits, 1))
{
int advance;
submode = speex_bits_unpack_unsigned(bits, 3);
advance = wb_skip_table[submode];
if (advance < 0) {
TRACE__((THIS_FUNC, "Invalid mode encountered. "
"The stream is corrupted."));
return -1;
}
TRACE__((THIS_FUNC, "WB layer skipped: %d bits", advance));
advance -= (SB_SUBMODE_BITS+1);
speex_bits_advance(bits, advance);
bit_ptr = bits->bitPtr;
char_ptr = bits->charPtr;
/* Consecutive subband frames may not exceed 2 frames */
if (++wb_count > 2)
return -1;
}
/* End of bits, return the frame */
if (speex_bits_remaining(bits) < 4) {
TRACE__((THIS_FUNC, "End of stream"));
return 0;
}
/* Stop iteration, return the frame */
if (nb_count > 0) {
bits->bitPtr = bit_ptr;
bits->charPtr = char_ptr;
return 0;
}
/* Get control bits */
submode = speex_bits_unpack_unsigned(bits, 4);
TRACE__((THIS_FUNC, "Control bits: %d at %d",
submode, bits->charPtr*8+bits->bitPtr));
if (submode == 15) {
TRACE__((THIS_FUNC, "Found submode: terminator"));
return -1;
} else if (submode == 14) {
/* in-band signal; next 4 bits contain signal id */
submode = speex_bits_unpack_unsigned(bits, 4);
TRACE__((THIS_FUNC, "Found submode: in-band %d bits",
inband_skip_table[submode]));
speex_bits_advance(bits, inband_skip_table[submode]);
} else if (submode == 13) {
/* user in-band; next 5 bits contain msg len */
submode = speex_bits_unpack_unsigned(bits, 5);
TRACE__((THIS_FUNC, "Found submode: user-band %d bytes", submode));
speex_bits_advance(bits, submode * 8);
} else if (submode > 8) {
TRACE__((THIS_FUNC, "Unknown sub-mode %d", submode));
return -1;
} else {
/* NB frame */
unsigned int advance = submode;
speex_mode_query(&speex_nb_mode, SPEEX_SUBMODE_BITS_PER_FRAME, &advance);
if (advance < 0) {
TRACE__((THIS_FUNC, "Invalid mode encountered. "
"The stream is corrupted."));
return -1;
}
TRACE__((THIS_FUNC, "Submode %d: %d bits", submode, advance));
advance -= (NB_SUBMODE_BITS+1);
speex_bits_advance(bits, advance);
++nb_count;
}
}
return 0;
}
/* Default handler for user callbacks: skip it */
int speex_default_user_handler(SpeexBits *bits, void *state, void *data)
{
int req_size = speex_bits_unpack_unsigned(bits, 4);
speex_bits_advance(bits, 5+8*req_size);
return 0;
}
