diff options
Diffstat (limited to 'gr-fec/lib/ccsds_encoder_impl.cc')
-rw-r--r-- | gr-fec/lib/ccsds_encoder_impl.cc | 194 |
1 files changed, 88 insertions, 106 deletions
diff --git a/gr-fec/lib/ccsds_encoder_impl.cc b/gr-fec/lib/ccsds_encoder_impl.cc index 4c873a5288..9b91be4c8b 100644 --- a/gr-fec/lib/ccsds_encoder_impl.cc +++ b/gr-fec/lib/ccsds_encoder_impl.cc @@ -31,120 +31,102 @@ #include <gnuradio/fec/viterbi.h> namespace gr { - namespace fec { - namespace code { - - generic_encoder::sptr - ccsds_encoder::make(int frame_size, int start_state, - cc_mode_t mode) - { - return generic_encoder::sptr - (new ccsds_encoder_impl(frame_size, start_state, mode)); - } - - ccsds_encoder_impl::ccsds_encoder_impl(int frame_size, int start_state, - cc_mode_t mode) - : generic_encoder("ccsds_encoder"), - d_start_state(static_cast<unsigned char>(start_state)), - d_mode(mode) - { - d_max_frame_size = frame_size; - set_frame_size(frame_size); - } - - ccsds_encoder_impl::~ccsds_encoder_impl() - { - } - - int - ccsds_encoder_impl::get_output_size() - { - return d_output_size; - } - - int - ccsds_encoder_impl::get_input_size() - { - return d_frame_size/8; // packed byte input - } - - const char* - ccsds_encoder_impl::get_input_conversion() - { - // Expects packed data input; tell wrapper to pack it. - return "pack"; - } - - bool - ccsds_encoder_impl::set_frame_size(unsigned int frame_size) - { - bool ret = true; - if(frame_size > d_max_frame_size) { - GR_LOG_INFO(d_logger, boost::format("tried to set frame to %1%; max possible is %2%") \ - % frame_size % d_max_frame_size); - frame_size = d_max_frame_size; - ret = false; - } - - d_frame_size = frame_size; - - if(d_mode == CC_TERMINATED) { - d_output_size = 2*(d_frame_size + 7 - 1); - } - else { - d_output_size = 2*d_frame_size; - } - - return ret; - } - - double - ccsds_encoder_impl::rate() - { - return 0.5; - } - - void - ccsds_encoder_impl::generic_work(void *in_buffer, void *out_buffer) - { - unsigned char *in = (unsigned char*) in_buffer; - unsigned char *out = (unsigned char*) out_buffer; - - unsigned char my_state = d_start_state; - - if(d_mode == CC_TAILBITING) { - // Grab K-1 (6) bits of data from the last input byte to add - // onto the from of the encoding stream for tailbiting mode. - unsigned char sym = in[d_frame_size/8 - 1]; - for(unsigned int i = 0; i < 7 - 1; ++i) { +namespace fec { +namespace code { + +generic_encoder::sptr ccsds_encoder::make(int frame_size, int start_state, cc_mode_t mode) +{ + return generic_encoder::sptr(new ccsds_encoder_impl(frame_size, start_state, mode)); +} + +ccsds_encoder_impl::ccsds_encoder_impl(int frame_size, int start_state, cc_mode_t mode) + : generic_encoder("ccsds_encoder"), + d_start_state(static_cast<unsigned char>(start_state)), + d_mode(mode) +{ + d_max_frame_size = frame_size; + set_frame_size(frame_size); +} + +ccsds_encoder_impl::~ccsds_encoder_impl() {} + +int ccsds_encoder_impl::get_output_size() { return d_output_size; } + +int ccsds_encoder_impl::get_input_size() +{ + return d_frame_size / 8; // packed byte input +} + +const char* ccsds_encoder_impl::get_input_conversion() +{ + // Expects packed data input; tell wrapper to pack it. + return "pack"; +} + +bool ccsds_encoder_impl::set_frame_size(unsigned int frame_size) +{ + bool ret = true; + if (frame_size > d_max_frame_size) { + GR_LOG_INFO(d_logger, + boost::format("tried to set frame to %1%; max possible is %2%") % + frame_size % d_max_frame_size); + frame_size = d_max_frame_size; + ret = false; + } + + d_frame_size = frame_size; + + if (d_mode == CC_TERMINATED) { + d_output_size = 2 * (d_frame_size + 7 - 1); + } else { + d_output_size = 2 * d_frame_size; + } + + return ret; +} + +double ccsds_encoder_impl::rate() { return 0.5; } + +void ccsds_encoder_impl::generic_work(void* in_buffer, void* out_buffer) +{ + unsigned char* in = (unsigned char*)in_buffer; + unsigned char* out = (unsigned char*)out_buffer; + + unsigned char my_state = d_start_state; + + if (d_mode == CC_TAILBITING) { + // Grab K-1 (6) bits of data from the last input byte to add + // onto the from of the encoding stream for tailbiting mode. + unsigned char sym = in[d_frame_size / 8 - 1]; + for (unsigned int i = 0; i < 7 - 1; ++i) { my_state = (my_state << 1) | ((sym >> (5 - i)) & 1); - } } - - my_state = encode(out, in, d_frame_size/8, my_state); - - if(d_mode == CC_TERMINATED) { - // encode works on bytes, but we are only adding some number - // of bits to the end of the frame, so we abuse the encode - // function by reshifting the start state within the - // for-loop and only taking the last two bits out of the - // encoded 2-bytes. - unsigned char end_bits[16]; - for(unsigned int i = 0; i < (7 - 1); ++i) { + } + + my_state = encode(out, in, d_frame_size / 8, my_state); + + if (d_mode == CC_TERMINATED) { + // encode works on bytes, but we are only adding some number + // of bits to the end of the frame, so we abuse the encode + // function by reshifting the start state within the + // for-loop and only taking the last two bits out of the + // encoded 2-bytes. + unsigned char end_bits[16]; + for (unsigned int i = 0; i < (7 - 1); ++i) { my_state = (my_state << 1) | ((d_start_state >> (7 - 2 - i)) & 1); encode(&end_bits[0], &my_state, 1, my_state); out[(i + d_frame_size) * 2 + 0] = end_bits[14]; out[(i + d_frame_size) * 2 + 1] = end_bits[15]; - } } + } - if(d_mode == CC_TRUNCATED) { - my_state = d_start_state; - } + if (d_mode == CC_TRUNCATED) { + my_state = d_start_state; + } - d_start_state = my_state; - } + d_start_state = my_state; +} - } /* namespace code */ - } /* namespace fec */ +} /* namespace code */ +} /* namespace fec */ } /* namespace gr */ |