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mirror of https://github.com/gnss-sdr/gnss-sdr synced 2024-10-31 23:26:22 +00:00

Adding c2bits sample stream to UDP custom source

This commit is contained in:
Javier Arribas 2023-06-09 14:09:18 +02:00
parent e484e73eca
commit be2e5d8d5e
2 changed files with 163 additions and 92 deletions

View File

@ -30,6 +30,11 @@
const int FIFO_SIZE = 1472000;
struct byte_2bit_struct
{
signed two_bit_sample : 2; // <- 2 bits wide only
};
/* 4 bytes IP address */
typedef struct gr_ip_address
{
@ -120,6 +125,11 @@ Gr_Complex_Ip_Packet_Source::Gr_Complex_Ip_Packet_Source(std::string src_device,
d_wire_sample_type = 1;
d_bytes_per_sample = d_n_baseband_channels * 2;
}
else if (wire_sample_type == "c2bits")
{
d_wire_sample_type = 5;
d_bytes_per_sample = d_n_baseband_channels;
}
else if (wire_sample_type == "c4bits")
{
d_wire_sample_type = 2;
@ -183,7 +193,8 @@ bool Gr_Complex_Ip_Packet_Source::stop()
bool Gr_Complex_Ip_Packet_Source::open()
{
std::array<char, PCAP_ERRBUF_SIZE> errbuf{};
boost::mutex::scoped_lock lock(d_mutex); // hold mutex for duration of this function
//boost::mutex::scoped_lock lock(d_mutex); // hold mutex for duration of this function
gr::thread::scoped_lock guard(d_setlock);
// open device for reading
descr = pcap_open_live(d_src_device.c_str(), 1500, 1, 1000, errbuf.data());
if (descr == nullptr)
@ -239,7 +250,7 @@ void Gr_Complex_Ip_Packet_Source::static_pcap_callback(u_char *args, const struc
void Gr_Complex_Ip_Packet_Source::pcap_callback(__attribute__((unused)) u_char *args, __attribute__((unused)) const struct pcap_pkthdr *pkthdr,
const u_char *packet)
{
boost::mutex::scoped_lock lock(d_mutex); // hold mutex for duration of this function
//boost::mutex::scoped_lock lock(d_mutex); // hold mutex for duration of this function
const gr_ip_header *ih;
const gr_udp_header *uh;
@ -320,6 +331,62 @@ void Gr_Complex_Ip_Packet_Source::my_pcap_loop_thread(pcap_t *pcap_handle)
void Gr_Complex_Ip_Packet_Source::demux_samples(const gr_vector_void_star &output_items, int num_samples_readed)
{
if (d_wire_sample_type == 5)
{
//interleaved 2-bit I 2-bit Q samples packed in bytes: 1 byte -> 2 complex samples
int nsample = 0;
byte_2bit_struct sample{}; // <- 2 bits wide only
int real;
int imag;
for (int nbyte = 0; nbyte < num_samples_readed / 2; nbyte++)
{
for (const auto &output_item : output_items)
{
// Read packed input sample (1 byte = 2 complex samples)
// * Packing Order
// * Most Significant Nibble - Sample n
// * Least Significant Nibble - Sample n+1
// * Bit Packing order in Nibble Q1 Q0 I1 I0
// normal
int8_t c = fifo_buff[fifo_read_ptr++];
// Q[n]
sample.two_bit_sample = (c >> 6) & 3;
imag = (2 * static_cast<int8_t>(sample.two_bit_sample) + 1);
// I[n]
sample.two_bit_sample = (c >> 4) & 3;
real = (2 * static_cast<int8_t>(sample.two_bit_sample) + 1);
if (d_IQ_swap)
{
static_cast<gr_complex *>(output_item)[nsample] = gr_complex(real, imag);
}
else
{
static_cast<gr_complex *>(output_item)[nsample] = gr_complex(imag, real);
}
// Q[n+1]
sample.two_bit_sample = (c >> 2) & 3;
imag = (2 * static_cast<int8_t>(sample.two_bit_sample) + 1);
// I[n+1]
sample.two_bit_sample = c & 3;
real = (2 * static_cast<int8_t>(sample.two_bit_sample) + 1);
if (d_IQ_swap)
{
static_cast<gr_complex *>(output_item)[nsample + 1] = gr_complex(real, imag);
}
else
{
static_cast<gr_complex *>(output_item)[nsample + 1] = gr_complex(imag, real);
}
}
}
}
else
{
for (int n = 0; n < num_samples_readed; n++)
{
@ -425,6 +492,7 @@ void Gr_Complex_Ip_Packet_Source::demux_samples(const gr_vector_void_star &outpu
}
}
}
}
int Gr_Complex_Ip_Packet_Source::work(int noutput_items,
@ -432,7 +500,7 @@ int Gr_Complex_Ip_Packet_Source::work(int noutput_items,
gr_vector_void_star &output_items)
{
// send samples to next GNU Radio block
boost::mutex::scoped_lock lock(d_mutex); // hold mutex for duration of this function
//boost::mutex::scoped_lock lock(d_mutex); // hold mutex for duration of this function
if (fifo_items == 0)
{
return 0;
@ -446,21 +514,24 @@ int Gr_Complex_Ip_Packet_Source::work(int noutput_items,
int num_samples_readed;
int bytes_requested;
bytes_requested = noutput_items * d_bytes_per_sample;
bytes_requested = static_cast<int>(static_cast<float>(noutput_items) * d_bytes_per_sample);
if (bytes_requested < fifo_items)
{
num_samples_readed = noutput_items; // read all
// update fifo items
fifo_items = fifo_items - bytes_requested;
}
else
{
num_samples_readed = fifo_items / d_bytes_per_sample; // read what we have
num_samples_readed = static_cast<int>(static_cast<float>(fifo_items) / d_bytes_per_sample); // read what we have
bytes_requested = fifo_items;
// update fifo items
fifo_items = 0;
}
bytes_requested = num_samples_readed * d_bytes_per_sample;
// read all in a single loop
demux_samples(output_items, num_samples_readed); // it also increases the fifo read pointer
// update fifo items
fifo_items = fifo_items - bytes_requested;
for (uint64_t n = 0; n < output_items.size(); n++)
{

View File

@ -83,7 +83,7 @@ private:
bool open();
boost::thread *d_pcap_thread;
boost::mutex d_mutex;
//boost::mutex d_mutex;
struct sockaddr_in si_me
{
};
@ -98,7 +98,7 @@ private:
int d_udp_port;
int d_n_baseband_channels;
int d_wire_sample_type;
int d_bytes_per_sample;
float d_bytes_per_sample;
bool d_IQ_swap;
};