fifo_destroy(m_rxUserdata->outfifo2);
fifo_destroy(m_rxUserdata->rxinfifo);
fifo_destroy(m_rxUserdata->rxoutfifo);
- fifo_destroy(m_rxUserdata->txinfifo);
- fifo_destroy(m_rxUserdata->txoutfifo);
}
int MainFrame::initPortAudioDevice(PortAudioWrap *pa, int inDevice, int outDevice, int soundCard)
// init params that affect input and output
+ /*
+ On a good day framesPerBuffer in callback will be PA_FPB. It
+ was found that you dont always get framesPerBuffer exactly
+ equal PA_PFB, for example when I wanted framesPerBuffer ==
+ PA_PFB == 960 samples.
+ */
pa->setFramesPerBuffer(PA_FPB);
pa->setSampleRate(SAMPLE_RATE);
pa->setStreamFlags(0);
// create FIFOs used to interface between different buffer sizes
m_rxUserdata->infifo1 = fifo_create(2*N48);
- m_rxUserdata->outfifo1 = fifo_create(2*N48);
+
+ /*
+ During soundcard 1 callback, outfifo1 is read in PA_FPB = 1024 sample blocks.
+
+ In tx processing:
+ + if outfifo1 has less than framesPerBuffer = PA_FPB = 1024 samples
+ + then tx process generates a 40ms @ 48kHz = 1920 sample blocks
+ + so we could have 1023 + 1920 samples
+ + so lets make it 1920*2 in size
+ */
+
+ m_rxUserdata->outfifo1 = fifo_create(4*N48);
+
m_rxUserdata->infifo2 = fifo_create(2*N48);
m_rxUserdata->outfifo2 = fifo_create(2*N48);
m_rxUserdata->rxinfifo = fifo_create(2 * FDMDV_NOM_SAMPLES_PER_FRAME);
m_rxUserdata->rxoutfifo = fifo_create(2 * codec2_samples_per_frame(g_pCodec2));
- m_rxUserdata->txinfifo = fifo_create(codec2_samples_per_frame(g_pCodec2));
- m_rxUserdata->txoutfifo = fifo_create(2 * FDMDV_NOM_SAMPLES_PER_FRAME);
// question: can same callback data be used for both callbacks?
// Is there a chance of them both being called at the same time?
// temp buffers re-used by tx and rx processing
short in8k_short[N8];
- float out8k[N8];
+ float out8k[2*N8];
short out8k_short[N8];
- float out48k[N48];
- short out48k_short[N48];
- short in48k_short[N48];
+ float out48k[2*N48];
+ short out48k_short[2*N48];
+ short in48k_short[2*N48];
short indata[MAX_FPB];
short outdata[MAX_FPB];
int ret;
- unsigned int i, nrxloops;
+ unsigned int i;
(void) timeInfo;
(void) statusFlags;
// while we have enough input samples available ...
- nrxloops = 0;
while (fifo_read(cbData->infifo1, in48k_short, N48) == 0)
{
// note: modifying fdmdv_48_to_8() to use shorts for sample I/O
fifo_write(cbData->outfifo1, out48k_short, N48);
else
fifo_write(cbData->outfifo2, out48k_short, N48);
-
- nrxloops++;
}
//
if (g_nSoundCards == 2 ) {
- // iterate tx as many times as rx, effectively locking tx
- // processing to sample rate of sound card 1. We want to make
- // sure that modulator samples are uninterrupted by
- // differences in sample rate between this sound card and
- // audio I/O soundcard 2.
+ // Make sure we have at least framesPerBuffer modulator output
+ // samples. This locks the modulator to the sample
+ // rate of sound card 1. We want to make sure that modulator
+ // samples are uninterrupted by differences in sample rate
+ // between this sound card and sound card 2.
- for(i=0; i<nrxloops; i++) {
+ // Typical values are framesPerBuffer=1024, and each iteration
+ // of the tx processing generates 320*FDMDV_OS=1920 samples at
+ // 48kHz, so this loop will run 0 or 1 times.
+
+ while((unsigned)fifo_n(cbData->outfifo1) < framesPerBuffer) {
+ short tx_speech_in[2*N8];
+ short tx_mod_out[2*N8];
// infifo2 is written to by another sound card so it may
// over or underflow, but we don't realy care. It will
// to codec2_enc, possibly making a click every now and
// again in the decoded audio at the other end.
- memset(in8k_short, 0, sizeof(short)*N8);
- fifo_read(cbData->infifo2, in8k_short, N8);
+ // zero speech input just in case infifo2 underflows
- short_to_float(&in48k2[FDMDV_OS_TAPS], in48k_short, N48);
- fdmdv_48_to_8(out8k, &in48k2[FDMDV_OS_TAPS], N8);
- float_to_short(out8k_short, out8k, N8);
- fifo_write(cbData->txinfifo, out8k_short, N8);
+ memset(in48k_short, 0, sizeof(short)*2*N48);
- per_frame_tx_processing(cbData->txoutfifo, cbData->txinfifo, g_pCodec2);
+ // Codec 2 @ 1400 bit/s requires 40ms of input speech
+
+ fifo_read(cbData->infifo2, in48k_short, 2*N48);
+ short_to_float(&in48k2[FDMDV_OS_TAPS], in48k_short, 2*N48);
+ fdmdv_48_to_8(out8k, &in48k2[FDMDV_OS_TAPS], 2*N8);
+ float_to_short(tx_speech_in, out8k, 2*N8);
+ assert(codec2_samples_per_frame(g_pCodec2) == (2*N8));
+
+ per_frame_tx_processing(tx_mod_out, tx_speech_in, g_pCodec2);
- while(fifo_read(cbData->txoutfifo, in8k_short, N8) == 0) {
- short_to_float(&in8k2[MEM8], in8k_short, N8);
- fdmdv_8_to_48(out48k, &in8k2[MEM8], N8);
- float_to_short(out48k_short, out48k, N48);
- //fifo_write(cbData->outfifo1, out48k_short, N48);
- }
+ // output 40ms of modem tone
+
+ short_to_float(&in8k2[MEM8], tx_mod_out, 2*N8);
+ fdmdv_8_to_48(out48k, &in8k2[MEM8], 2*N8);
+ float_to_short(out48k_short, out48k, 2*N48);
+ fifo_write(cbData->outfifo1, out48k_short, 2*N48);
}
}
}
void MainFrame::per_frame_tx_processing(
- FIFO *output_fifo, // ouput modulated samples
- FIFO *input_fifo, // speech sample input
+ short tx_fdm_scaled[],// ouput modulated samples
+ short input_buf[], // speech sample input
CODEC2 *c2 // Codec 2 states
)
{
- short input_buf[2*N8];
unsigned char packed_bits[BYTES_PER_CODEC_FRAME];
int bits[BITS_PER_CODEC_FRAME];
COMP tx_fdm[2*FDMDV_NOM_SAMPLES_PER_FRAME];
- short tx_fdm_scaled[2*FDMDV_NOM_SAMPLES_PER_FRAME];
int sync_bit;
int i, bit, byte;
- assert(codec2_samples_per_frame(c2) <= (2*N8));
+ codec2_encode(c2, packed_bits, input_buf);
- while (fifo_read(input_fifo, input_buf, codec2_samples_per_frame(c2)) == 0) {
- codec2_encode(c2, packed_bits, input_buf);
+ /* unpack bits, MSB first */
- /* unpack bits, MSB first */
-
- bit = 7; byte = 0;
- for(i=0; i<BITS_PER_CODEC_FRAME; i++) {
- bits[i] = (packed_bits[byte] >> bit) & 0x1;
- bit--;
- if (bit < 0) {
- bit = 7;
- byte++;
- }
+ bit = 7; byte = 0;
+ for(i=0; i<BITS_PER_CODEC_FRAME; i++) {
+ bits[i] = (packed_bits[byte] >> bit) & 0x1;
+ bit--;
+ if (bit < 0) {
+ bit = 7;
+ byte++;
}
- assert(byte == BYTES_PER_CODEC_FRAME);
+ }
+ assert(byte == BYTES_PER_CODEC_FRAME);
- /* modulate even and odd frames */
+ /* modulate even and odd frames */
- fdmdv_mod(g_pFDMDV, tx_fdm, bits, &sync_bit);
- assert(sync_bit == 1);
+ fdmdv_mod(g_pFDMDV, tx_fdm, bits, &sync_bit);
+ assert(sync_bit == 1);
- fdmdv_mod(g_pFDMDV, &tx_fdm[FDMDV_NOM_SAMPLES_PER_FRAME], &bits[FDMDV_BITS_PER_FRAME], &sync_bit);
- assert(sync_bit == 0);
+ fdmdv_mod(g_pFDMDV, &tx_fdm[FDMDV_NOM_SAMPLES_PER_FRAME], &bits[FDMDV_BITS_PER_FRAME], &sync_bit);
+ assert(sync_bit == 0);
- /* scale and convert shorts */
+ /* scale and convert shorts */
- for(i=0; i<2*FDMDV_NOM_SAMPLES_PER_FRAME; i++)
- tx_fdm_scaled[i] = FDMDV_SCALE * tx_fdm[i].real;
+ for(i=0; i<2*FDMDV_NOM_SAMPLES_PER_FRAME; i++)
+ tx_fdm_scaled[i] = FDMDV_SCALE * tx_fdm[i].real;
- fifo_write(output_fifo, tx_fdm_scaled, 2*FDMDV_NOM_SAMPLES_PER_FRAME);
- }
}
//-------------------------------------------------------------------------
projects / freetel-svn-tracking.git / commitdiff