osmo-gmr/src/gmr1_gen_mat.c

104 lines
2.3 KiB
C

/* GMR-1 G/g matrix geneation for FACCH3 */
/* (C) 2011-2019 by Sylvain Munaut <tnt@246tNt.com>
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <osmocom/core/bits.h>
#include <osmocom/core/utils.h>
#include <osmocom/gmr1/l1/facch3.h>
static void
copy_bits(ubit_t *dst, int dst_col, int n_col, ubit_t *bits_e)
{
int i, j;
for (i=0; i<4; i++) {
for (j=0; j<96; j++) {
int si = (104 * i) + ((j < 22) ? j : (j+8));
int di = dst_col + (((i*96)+j) * n_col);
dst[di] = bits_e[si];
}
}
}
static int
pbm_save_bits(const char *filename, ubit_t *m, int x, int y)
{
FILE *fh;
int i, j;
fh = fopen(filename, "w");
if (!fh)
return -EPERM;
fprintf(fh, "P1\n%d %d\n", x, y);
for (i=0; i<y; i++)
for (j=0; j<x; j++)
fprintf(fh, "%d%c", m[(i*x)+j], j==x-1 ? '\n' : ' ');
fclose(fh);
return 0;
}
int main(int argc, char *argv[])
{
ubit_t mat_G[384*76]; /* 384 lines of 76 pixels */
ubit_t mat_g[384]; /* 384 lines of 1 pixel */
ubit_t bits_e[104*4];
ubit_t bits_u[76];
ubit_t bits_s[8*4];
uint8_t l2[10];
int i, j;
memset(mat_G, 0x00, sizeof(mat_G));
memset(mat_g, 0x00, sizeof(mat_g));
memset(bits_s, 0x00, sizeof(bits_s));
memset(l2, 0x00, sizeof(l2));
gmr1_facch3_encode(bits_e, l2, bits_s, NULL);
copy_bits(mat_g, 0, 1, bits_e);
for (i=0; i<76; i++) {
memset(bits_u, 0, sizeof(bits_u));
bits_u[i] = 1;
osmo_ubit2pbit_ext(l2, 0, bits_u, 0, 76, 1);
gmr1_facch3_encode(bits_e, l2, bits_s, NULL);
copy_bits(mat_G, i, 76, bits_e);
}
for (i=0; i<76; i++) {
for (j=0; j<384; j++) {
mat_G[(j*76)+i] ^= mat_g[j];
}
}
pbm_save_bits("mat_G.pbm", mat_G, 76, 384);
pbm_save_bits("mat_g.pbm", mat_g, 1, 384);
return 0;
}