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/* -*- c++ -*- */
/*
* @file
* @author (C) 2018 by Vasil Velichkov <vvvelichkov@gmail.com>
* @section LICENSE
*
* Gr-gsm is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3, or (at your option)
* any later version.
*
* Gr-gsm 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with gr-gsm; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gsm/gsmtap.h>
#include <gsm/endian.h>
#include "tch_h_decoder_impl.h"
#include <iomanip>
extern "C" {
#include "osmocom/gsm/protocol/gsm_04_08.h"
#include "osmocom/coding/gsm0503_coding.h"
}
namespace gr {
namespace gsm {
static int ubits2sbits(ubit_t *ubits, sbit_t *sbits, int count)
{
int i;
for (i = 0; i < count; i++) {
if (*ubits == 0x23) {
ubits++;
sbits++;
continue;
}
if ((*ubits++) & 1)
*sbits++ = -127;
else
*sbits++ = 127;
}
return count;
}
tch_h_decoder::sptr
tch_h_decoder::make(unsigned int sub_channel, std::string multi_rate, bool boundary_check)
{
return gnuradio::get_initial_sptr
(new tch_h_decoder_impl(sub_channel, multi_rate, boundary_check));
}
/*
* Constructor
*/
tch_h_decoder_impl::tch_h_decoder_impl(unsigned int sub_channel, std::string multi_rate, bool boundary_check)
: gr::block("tch_h_decoder",
gr::io_signature::make(0, 0, 0),
gr::io_signature::make(0, 0, 0)),
d_collected_bursts_num(0),
d_tch_mode(TCH_HS),
d_sub_channel(sub_channel),
d_boundary_check(boundary_check),
d_boundary_decode(false),
d_header_sent(false),
d_ft(0),
d_cmr(0)
{
//setup input/output ports
message_port_register_in(pmt::mp("bursts"));
set_msg_handler(pmt::mp("bursts"), boost::bind(&tch_h_decoder_impl::decode, this, boost::placeholders::_1));
message_port_register_out(pmt::mp("msgs"));
message_port_register_out(pmt::mp("voice"));
if(multi_rate.length())
{
std::cout<<"multi_rate configuration: "<<multi_rate<<std::endl;
if (multi_rate.length() < 4 || multi_rate.length() % 2)
{
throw std::invalid_argument("Invalid multi_rate hexstring");
}
std::vector<uint8_t> binary;
for (std::string::const_iterator it = multi_rate.begin();
it != multi_rate.end(); it += 2)
{
std::string byte(it, it + 2);
char* end = NULL;
errno = 0;
uint8_t b = strtoul(byte.c_str(), &end, 16);
if (errno != 0 || *end != '\0')
{
throw std::invalid_argument("Invalid multi_rate hexstring");
}
binary.push_back(b);
}
if (binary.size() < 2) {
throw std::invalid_argument("The multi_rate is too short");
}
//GSM A-I/F DTAP - Assignment Command
// Protocol Discriminator: Radio Resources Management messages (6)
// DTAP Radio Resources Management Message Type: Assignment Command (0x2e)
// Channel Description 2 - Description of the First Channel, after time
// Power Command
// Channel Mode - Mode of the First Channel(Channel Set 1)
// MultiRate configuration
// Element ID: 0x03
// Length: 4
// 001. .... = Multirate speech version: Adaptive Multirate speech version 1 (1)
// ...0 .... = NSCB: Noise Suppression Control Bit: Noise Suppression can be used (default) (0)
// .... 1... = ICMI: Initial Codec Mode Indicator: The initial codec mode is defined by the Start Mode field (1)
// .... ..00 = Start Mode: 0
// 0... .... = 12,2 kbit/s codec rate: is not part of the subset
// .0.. .... = 10,2 kbit/s codec rate: is not part of the subset
// ..0. .... = 7,95 kbit/s codec rate: is not part of the subset
// ...1 .... = 7,40 kbit/s codec rate: is part of the subset
// .... 0... = 6,70 kbit/s codec rate: is not part of the subset
// .... .0.. = 5,90 kbit/s codec rate: is not part of the subset
// .... ..0. = 5,15 kbit/s codec rate: is not part of the subset
// .... ...1 = 4,75 kbit/s codec rate: is part of the subset
// ..01 1010 = AMR Threshold: 13.0 dB (26)
// 0100 .... = AMR Hysteresis: 2.0 dB (4)
const uint8_t first = binary[0];
uint8_t multirate_speech_ver = (first >> 5) & 0x07;
if (multirate_speech_ver == 1)
{
d_tch_mode = TCH_AFS4_75;
}
else if (multirate_speech_ver == 2)
{
throw std::invalid_argument("Adaptive Multirate speech version 2 is not supported");
}
else
{
throw std::invalid_argument("Multirate speech version");
}
bool ncsb = (first >> 4) & 0x01;
bool icmi = (first >> 3) & 0x01;
uint8_t start = first & 0x03;
const uint8_t codecs = binary[1];
for (int i = 0; i < 8; i++)
{
if ((codecs >> i) & 1)
{
d_multi_rate_codes.push_back(i);
}
}
std::cout<<"Enabled AMR Codecs:"<<std::endl;
for(std::vector<uint8_t>::const_iterator it = d_multi_rate_codes.begin();
it != d_multi_rate_codes.end();
it ++)
{
switch(*it)
{
case 0:
std::cout<<"4,75 kbit/s codec rate: is part of the subset"<<std::endl;
break;
case 1:
std::cout<<"5,15 kbit/s codec rate: is part of the subset"<<std::endl;
break;
case 2:
std::cout<<"5,90 kbit/s codec rate: is part of the subset"<<std::endl;
break;
case 3:
std::cout<<"6,70 kbit/s codec rate: is part of the subset"<<std::endl;
break;
case 4:
std::cout<<"7,40 kbit/s codec rate: is part of the subset"<<std::endl;
break;
case 5:
std::cout<<"7,95 kbit/s codec rate: is part of the subset"<<std::endl;
break;
case 6:
std::cout<<"12,2 kbit/s codec rate: is part of the subset"<<std::endl;
}
}
if (d_multi_rate_codes.size() > 4) {
throw std::invalid_argument("More then 4 multirate codes");
}
}
}
tch_h_decoder_impl::~tch_h_decoder_impl()
{
}
void tch_h_decoder_impl::decode(pmt::pmt_t msg)
{
d_bursts[d_collected_bursts_num++] = msg;
if (d_collected_bursts_num <= 7)
{
return;
}
gsmtap_hdr* header = (gsmtap_hdr*)(pmt::blob_data(pmt::cdr(msg)));
uint32_t frame_nr = be32toh(header->frame_number);
bool uplink_burst = (be16toh(header->arfcn) & 0x4000) ? true : false;
//TODO: Check in 3gpp specs which frames could contains facch/h frames
//and replace this ugly formula with table
int fn_is_odd = (((frame_nr - (uplink_burst ? 10 : 15)) % 26) >> 2) & 1;
ubit_t bursts_u[116 * 6] = {0}; //facch/h is 6 bursts
//reorganize data
for (int ii = 0; ii < 8; ii++)
{
//skip the 4th and 5th bursts
if (ii == 4 || ii == 5) continue;
int8_t* burst_bits = (int8_t*)(pmt::blob_data(pmt::cdr(d_bursts[ii])))+sizeof(gsmtap_hdr);
//copy 6th and 7th burst to 4th and 5th position
int n = ii < 6 ? ii : ii - 2;
memcpy(&bursts_u[n*116], &burst_bits[3],58);
memcpy(&bursts_u[n*116+58], &burst_bits[3+57+1+26],58);
}
//Convert to sbits
sbit_t bursts_s[116 * 6] = {0};
ubits2sbits(bursts_u, bursts_s, 116 * 6);
//Prepare burst for the next iteration by shifting them by 4
for (int ii = 0; ii < 4; ii++) {
d_bursts[ii] = d_bursts[ii + 4];
}
d_collected_bursts_num = 4;
uint8_t frameBuffer[64];
int frameLength = -1;
int n_errors, n_bits_total;
if (d_tch_mode == TCH_HS)
{
frameLength = gsm0503_tch_hr_decode(frameBuffer, bursts_s, fn_is_odd, &n_errors, &n_bits_total);
}
else
{
frameLength = gsm0503_tch_ahs_decode(frameBuffer, bursts_s, fn_is_odd,
fn_is_odd, //int codec_mode_req,
&d_multi_rate_codes.front(), d_multi_rate_codes.size(),
&d_ft,
&d_cmr,
&n_errors, &n_bits_total);
}
if (frameLength < 12)
{
#if 0
if (!d_boundary_check || d_boundary_decode) {
std::cerr<<"Error! frame_nr:"<<frame_nr<<" mod26:"<<frame_nr%26
<<" fn_is_odd:"<<fn_is_odd<<" length:"<<frameLength<<std::endl;
}
#endif
return;
}
else if (frameLength == GSM_MACBLOCK_LEN) //FACCH/H
{
pmt::pmt_t first_header_plus_burst = pmt::cdr(d_bursts[0]);
gsmtap_hdr* header = (gsmtap_hdr *)pmt::blob_data(first_header_plus_burst);
int8_t header_plus_data[sizeof(gsmtap_hdr)+frameLength];
memcpy(header_plus_data, header, sizeof(gsmtap_hdr));
memcpy(header_plus_data+sizeof(gsmtap_hdr), frameBuffer, frameLength);
((gsmtap_hdr*)header_plus_data)->type = GSMTAP_TYPE_UM;
pmt::pmt_t msg_binary_blob = pmt::make_blob(header_plus_data, frameLength + sizeof(gsmtap_hdr));
pmt::pmt_t msg_out = pmt::cons(pmt::PMT_NIL, msg_binary_blob);
message_port_pub(pmt::mp("msgs"), msg_out);
// if d_boundary_check is enabled, we set d_boundary_decode to true, when a
// "Connect" or "Connect Acknowledge" message is received, and
// we set d_boundary_decode back to false, when "Release" message is received
if (d_boundary_check)
{
// check if this is a call control message
if ((frameBuffer[3] & 0x0f) == 0x03)
{
// Alerting
if ((frameBuffer[4] & 0x3f) == 0x01)
{
if ((frameBuffer[5] == 0x1e) && //element id
(frameBuffer[6] == 2) && //length
((frameBuffer[8] & 0x7f) == 0x08))
{
std::cout << "(CC) Alerting with In-band information" << std::endl;
//.000 1000 = Progress description: In-band information or appropriate pattern now available (8)
d_boundary_decode = true;
}
}
// Progress
else if ((frameBuffer[4] & 0x3f) == 0x03)
{
if ((frameBuffer[5] == 2) && //length
(frameBuffer[7] & 0x7f) == 0x08)
{
std::cout << "(CC) Progress with In-band information" << std::endl;
//.000 1000 = Progress description: In-band information or appropriate pattern now available (8)
d_boundary_decode = true;
}
}
// Connect specified in GSM 04.08, 9.3.5
else if ((frameBuffer[4] & 0x3f) == 0x07)
{
std::cout << "(CC) Connect" << std::endl;
d_boundary_decode = true;
}
// Connect Acknowledge specified in GSM 04.08, 9.3.6
else if ((frameBuffer[4] & 0x3f) == 0x0f)
{
std::cout << "(CC) Connect Acknowledge" << std::endl;
d_boundary_decode = true;
}
// Release specified in GSM 04.08, 9.3.18
else if ((frameBuffer[4] & 0x3f) == 0x2d)
{
std::cout << "(CC) Release" << std::endl;
d_boundary_decode = false;
}
}
}
return;
}
if (!d_header_sent && d_tch_mode != TCH_HS)
{
const unsigned char amr_nb_magic[7] = "#!AMR\n";
message_port_pub(pmt::mp("voice"), pmt::cons(pmt::PMT_NIL, pmt::make_blob(amr_nb_magic, 6)));
d_header_sent = true;
}
if (!n_errors && (!d_boundary_check || d_boundary_decode))
{
//std::cerr<<"Voice frame_nr:"<<frame_nr<<" mod26:"<<frame_nr%26<<" is_odd:"<<fn_is_odd
// <<" type:"<<(uint32_t)d_ft<<" cmr:"<<(uint32_t)d_cmr
// <<" errors:"<<n_errors<<std::endl;
if (d_tch_mode != TCH_HS)
{
//Move one byte to make space for the header
memmove(frameBuffer + 1, frameBuffer, frameLength);
//Add the AMR header
switch(frameLength)
{
case 12: frameBuffer[0] = (0 << 3); break; //TCH/AHS4.75
case 13: frameBuffer[0] = (1 << 3); break; //TCH/AHS5.15
case 15: frameBuffer[0] = (2 << 3); break; //TCH/AHS5.9
case 17: frameBuffer[0] = (3 << 3); break; //TCH/AHS6.7
case 19: frameBuffer[0] = (4 << 3); break; //TCH/AHS7.4
case 20: frameBuffer[0] = (5 << 3); break; //TCH/AHS7.95
default: std::cerr<<"Unexpected voice frame length:"<<frameLength<<std::endl; return;
}
frameLength += 1;
}
//std::ostringstream out;
//out << "voice frame: ";
//for (int i = 0; i < frameLength; i++)
// out << " " << (std::hex) << std::setw(2) << std::setfill('0') << (uint32_t)*(frameBuffer + i);
//std::cerr << out.str() << std::endl;
message_port_pub(pmt::mp("voice"), pmt::cons(pmt::PMT_NIL, pmt::make_blob(frameBuffer, frameLength)));
}
}
} /* namespace gsm */
} /* namespace gr */
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