diff options
author | Harald Welte <laforge@gnumonks.org> | 2008-12-01 10:28:04 +0530 |
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committer | Harald Welte <laforge@gnumonks.org> | 2008-12-01 10:28:04 +0530 |
commit | 10f2fcca8dd1be2719bccefa16fd9dac9a76c749 (patch) | |
tree | 0b521a2ccc7d0d81a89e08b05650dec2421777d2 /gsmstack/interleave.c | |
parent | fd405f799425b6832a0c9cc7a56b07f43288b8b1 (diff) |
[gsmdecode] import {interleave,conv}.[ch] from gsm-tvoid
* change convolutional decode to cope with TCH
* add tch.c file with reordering/decoding for TCH/F
Diffstat (limited to 'gsmstack/interleave.c')
-rw-r--r-- | gsmstack/interleave.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/gsmstack/interleave.c b/gsmstack/interleave.c new file mode 100644 index 0000000..7899274 --- /dev/null +++ b/gsmstack/interleave.c @@ -0,0 +1,48 @@ +/* This file was taken from gsm-tvoid */ + +#include <stdlib.h> +#include <stdio.h> +#include "interleave.h" + +int +interleave_init(INTERLEAVE_CTX *ictx, int size, int block_size) +{ + ictx->trans_size = size; + ictx->trans = (unsigned short *)malloc(size * sizeof *ictx->trans); + +// DEBUGF("size: %d\n", size); +// DEBUGF("Block size: %d\n", block_size); + int j, k, B; + for (k = 0; k < size; k++) + { + B = k % 4; + j = 2 * ((49 * k) % 57) + ((k % 8) / 4); + ictx->trans[k] = B * block_size + j; + /* Mapping: pos1 goes to pos2: pos1 -> pos2 */ +// DEBUGF("%d -> %d\n", ictx->trans[k], k); + } +// exit(0); + return 0; +} + +int +interleave_deinit(INTERLEAVE_CTX *ictx) +{ + if (ictx->trans != NULL) + { + free(ictx->trans); + ictx->trans = NULL; + } + + return 0; +} + +void +interleave_decode(INTERLEAVE_CTX *ictx, unsigned char *dst, unsigned char *src) +{ + + int k; + for (k = 0; k < ictx->trans_size; k++) + dst[k] = src[ictx->trans[k]]; +} + |