diff options
Diffstat (limited to 'lib/decoding/tch_f_decoder_impl.cc')
| -rw-r--r-- | lib/decoding/tch_f_decoder_impl.cc | 51 |
1 files changed, 43 insertions, 8 deletions
diff --git a/lib/decoding/tch_f_decoder_impl.cc b/lib/decoding/tch_f_decoder_impl.cc index 5b77be2..1f22cf2 100644 --- a/lib/decoding/tch_f_decoder_impl.cc +++ b/lib/decoding/tch_f_decoder_impl.cc @@ -1,7 +1,8 @@ /* -*- c++ -*- */ /* * @file - * @author Roman Khassraf <rkhassraf@gmail.com> + * @author (C) 2015 by Roman Khassraf <rkhassraf@gmail.com> + * (C) 2017 by Piotr Krysik <ptrkrysik@gmail.com> * @section LICENSE * * Gr-gsm is free software; you can redistribute it and/or modify @@ -296,26 +297,60 @@ namespace gr { unsigned tail = mTCHU.peekField(185, 4); bool good = (sentParity == calcParity) && (tail == 0); - if (good) { uint8_t frameBuffer[33]; - sbit_t bursts_s[116 * 8]; - int n_errors, n_bits_total; + sbit_t bursts_s[116 * 8]; + int n_errors, n_bits_total; unsigned int mTCHFrameLength; - - ubits2sbits(bursts_u, bursts_s, 116 * 8); + ubits2sbits(bursts_u, bursts_s, 116 * 8); if (d_tch_mode == TCH_FS) // GSM-FR { mTCHFrameLength = 33; gsm0503_tch_fr_decode(frameBuffer, bursts_s, 1, 0, &n_errors, &n_bits_total); - std::cout << "Errors: " << n_errors << std::endl; + //std::cout << "Errors: " << n_errors << std::endl; } else if (d_tch_mode == TCH_EFR) // GSM-EFR { + unsigned char mFrameHeader = 0x3c; + + // AMR Frame, consisting of a 8 bit frame header, plus the payload from decoding + BitVector amrFrame(244 + 8); // Same output length as AMR 12.2 + BitVector payload = amrFrame.tail(8); + + BitVector TCHW(260), EFRBits(244); + + // write frame header + amrFrame.fillField(0, mFrameHeader, 8); + + // Undo Um's EFR bit ordering. + mTCHD.unmap(GSM::g660BitOrder, 260, TCHW); + + // Remove repeating bits and CRC to get raw EFR frame (244 bits) + for (unsigned k=0; k<71; k++) + EFRBits[k] = TCHW[k] & 1; + + for (unsigned k=73; k<123; k++) + EFRBits[k-2] = TCHW[k] & 1; + + for (unsigned k=125; k<178; k++) + EFRBits[k-4] = TCHW[k] & 1; + + for (unsigned k=180; k<230; k++) + EFRBits[k-6] = TCHW[k] & 1; + + for (unsigned k=232; k<252; k++) + EFRBits[k-8] = TCHW[k] & 1; + + // Map bits as AMR 12.2k + EFRBits.map(GSM::gAMRBitOrderTCH_AFS12_2, 244, payload); + + // Put the whole frame (hdr + payload) mTCHFrameLength = 32; - gsm0503_tch_fr_decode(frameBuffer, bursts_s, 1, 1, &n_errors, &n_bits_total); + amrFrame.pack(frameBuffer); + //when itegrating with libosmocore lines above can be removed and line below uncommented, efr decoding with libosmocore need to be tested however + //gsm0503_tch_fr_decode(frameBuffer, bursts_s, 1, 1, &n_errors, &n_bits_total); } message_port_pub(pmt::mp("voice"), pmt::cons(pmt::PMT_NIL, pmt::make_blob(frameBuffer,mTCHFrameLength))); } |