3 * Copyright 2006 Free Software Foundation, Inc.
5 * This file is part of GNU Radio
7 * GNU Radio is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 3, or (at your option)
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13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with GNU Radio; see the file COPYING. If not, write to
19 * the Free Software Foundation, Inc., 51 Franklin Street,
20 * Boston, MA 02110-1301, USA.
28 #include <atsc_field_sync_demux.h>
29 #include <gr_io_signature.h>
30 #include <atsc_types.h>
31 #include <atsc_consts.h>
32 #include <atsci_syminfo.h>
41 static const int DEC = ATSC_DATA_SEGMENT_LENGTH; // nominal decimation factor
44 atsc_field_sync_demux_sptr
45 atsc_make_field_sync_demux()
47 return atsc_field_sync_demux_sptr(new atsc_field_sync_demux());
50 atsc_field_sync_demux::atsc_field_sync_demux()
51 : gr_block("atsc_field_sync_demux",
52 gr_make_io_signature(2, 2, sizeof(float)),
53 gr_make_io_signature(1, 1, sizeof(atsc_soft_data_segment))),
54 d_locked(false), d_in_field2(true), d_segment_number(0),
55 d_next_input(0), d_lost_index(0), d_inputs0_index(0),
56 d_inputs0_size(0), d_consume(0)
62 tag_is_seg_sync_or_field_sync (atsc::syminfo tag)
64 return tag.symbol_num == 0 && tag.valid;
68 atsc_field_sync_demux::forecast (int noutput_items, gr_vector_int &ninput_items_required)
70 unsigned ninputs = ninput_items_required.size();
71 for (unsigned i = 0; i < ninputs; i++) {
72 ninput_items_required[i] = noutput_items * DEC + 2 * DEC ;
74 d_inputs0_index = d_next_input;
75 d_inputs0_size = noutput_items * DEC + 2 * DEC ;
80 atsc_field_sync_demux::general_work (int noutput_items,
81 gr_vector_int &ninput_items,
82 gr_vector_const_void_star &input_items,
83 gr_vector_void_star &output_items)
85 int r = work (noutput_items, input_items, output_items);
86 consume_each (d_consume);
87 // printf("Consumed: %d, produced: %d\n",d_consume,r);
88 // we consume input even if no output is produced
89 // while looking for sync
95 atsc_field_sync_demux::work (int noutput_items,
96 gr_vector_const_void_star &input_items,
97 gr_vector_void_star &output_items)
99 float *in = (float *) input_items[0];
100 atsc::syminfo *input_tags = (atsc::syminfo *) input_items[1];
101 atsc_soft_data_segment *out = (atsc_soft_data_segment *) output_items[0];
103 assert(sizeof(float) == sizeof(atsc::syminfo));
105 unsigned int ii = 0; // input index
108 if (!tag_is_seg_sync_or_field_sync (input_tags[0])){ // No ...
112 d_lost_index = d_inputs0_index + ii;
113 cerr << "atsc_field_sync_demux: lost sync at "
114 << d_lost_index << endl;
117 // ... search for beginning of a field sync
119 // cerr << "atsc_field_sync_demux: searching for sync at "
120 // << d_inputs0_index + ii << endl;
122 for (ii = 1; ii < d_inputs0_size; ii++){
123 if (atsc::tag_is_start_field_sync (input_tags[ii])){
128 if (atsc::tag_is_start_field_sync_1 (input_tags[ii]))
130 else if (atsc::tag_is_start_field_sync_2 (input_tags[ii]))
135 cerr << "atsc_field_sync_demux: synced (" << str << ") at "
136 << d_inputs0_index + ii
137 << " [delta = " << d_inputs0_index + ii - d_lost_index
140 d_next_input += ii; // update for forecast
142 return 0; // no work completed so far
145 // no non-NORMAL tag found
146 d_next_input += ii; // update for forecast
148 // printf("ii: %d, d_next_input: %d\n",ii,d_next_input);
149 return 0; // no work completed so far
152 // We are in sync. Produce output...
154 int k = 0; // output index
156 while (k < noutput_items){
158 if (d_inputs0_size - ii < static_cast<unsigned int>(ATSC_DATA_SEGMENT_LENGTH)){
159 // We're out of input data.
160 cerr << "atsc_field_sync_demux: ran out of input data\n";
161 d_next_input += ii; // update for forecast
162 return k; // return amount of work completed so far
165 if (!tag_is_seg_sync_or_field_sync (input_tags[ii])){
167 cerr << "atsc_field_sync_demux: lost sync at "
168 << d_inputs0_index + ii << endl;
170 d_next_input += ii; // update for forecast
171 return k; // return amount of work completed so far
174 if (atsc::tag_is_start_field_sync_1 (input_tags[ii])){
176 d_segment_number = 0;
177 ii += ATSC_DATA_SEGMENT_LENGTH; // skip over field sync
181 if (atsc::tag_is_start_field_sync_2 (input_tags[ii])){
183 d_segment_number = 0;
184 ii += ATSC_DATA_SEGMENT_LENGTH; // skip over field sync
188 if (d_segment_number >= ATSC_DSEGS_PER_FIELD){
189 // something's wrong...
190 cerr << "atsc_field_sync_demux: segment number overflow\n";
191 d_segment_number = 0;
194 out[k].pli.set_regular_seg (d_in_field2, d_segment_number++);
195 for (int jj = 0; jj < ATSC_DATA_SEGMENT_LENGTH; jj++)
196 out[k].data[jj] = in[ii + jj];
197 ii += ATSC_DATA_SEGMENT_LENGTH;
201 d_next_input += ii; // update for forecast
203 return k; // return amount of work completed