libosmocore  1.5.1
Osmocom core library
conv.h
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1 
3 /*
4  * Copyright (C) 2011 Sylvain Munaut <tnt@246tNt.com>
5  *
6  * All Rights Reserved
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License along
19  * with this program; if not, write to the Free Software Foundation, Inc.,
20  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
21  */
22 
27 #pragma once
28 
29 #include <stdint.h>
30 
31 #include <osmocom/core/bits.h>
32 
44 };
45 
53  int N;
54  int K;
55  int len;
57  enum osmo_conv_term term;
59  const uint8_t (*next_output)[2];
60  const uint8_t (*next_state)[2];
62  const uint8_t *next_term_output;
63  const uint8_t *next_term_state;
65  const int *puncture;
66 };
67 
68 
69 /* Common */
70 
71 int osmo_conv_get_input_length(const struct osmo_conv_code *code, int len);
72 int osmo_conv_get_output_length(const struct osmo_conv_code *code, int len);
73 
74 
75 /* Encoding */
76 
77  /* Low level API */
78 
81  const struct osmo_conv_code *code;
82  int i_idx;
83  int p_idx;
84  uint8_t state;
85 };
86 
87 void osmo_conv_encode_init(struct osmo_conv_encoder *encoder,
88  const struct osmo_conv_code *code);
90  const ubit_t *input);
91 int osmo_conv_encode_raw(struct osmo_conv_encoder *encoder,
92  const ubit_t *input, ubit_t *output, int n);
93 int osmo_conv_encode_flush(struct osmo_conv_encoder *encoder, ubit_t *output);
94 
95  /* All-in-one */
96 int osmo_conv_encode(const struct osmo_conv_code *code,
97  const ubit_t *input, ubit_t *output);
98 
99 
100 /* Decoding */
101 
102  /* Low level API */
103 
106  const struct osmo_conv_code *code;
108  int n_states;
110  int len;
112  int o_idx;
113  int p_idx;
115  unsigned int *ae;
116  unsigned int *ae_next;
117  uint8_t *state_history;
118 };
119 
120 void osmo_conv_decode_init(struct osmo_conv_decoder *decoder,
121  const struct osmo_conv_code *code,
122  int len, int start_state);
123 void osmo_conv_decode_reset(struct osmo_conv_decoder *decoder, int start_state);
124 void osmo_conv_decode_rewind(struct osmo_conv_decoder *decoder);
125 void osmo_conv_decode_deinit(struct osmo_conv_decoder *decoder);
126 
127 int osmo_conv_decode_scan(struct osmo_conv_decoder *decoder,
128  const sbit_t *input, int n);
129 int osmo_conv_decode_flush(struct osmo_conv_decoder *decoder,
130  const sbit_t *input);
132  ubit_t *output, int has_flush, int end_state);
133 
134  /* All-in-one */
135 int osmo_conv_decode(const struct osmo_conv_code *code,
136  const sbit_t *input, ubit_t *output);
137 
138 
osmo_conv_decoder::state_history
uint8_t * state_history
state history [len][n_states]
Definition: conv.h:117
osmo_conv_encoder::i_idx
int i_idx
Next input bit index.
Definition: conv.h:82
osmo_conv_decoder::p_idx
int p_idx
puncture index
Definition: conv.h:113
CONV_TERM_TRUNCATION
@ CONV_TERM_TRUNCATION
Direct truncation.
Definition: conv.h:42
osmo_conv_encoder::p_idx
int p_idx
Current puncture index.
Definition: conv.h:83
osmo_conv_code::term
enum osmo_conv_term term
Termination type.
Definition: conv.h:57
osmo_conv_decoder::ae_next
unsigned int * ae_next
next accumulated error (tmp in scan)
Definition: conv.h:116
osmo_conv_encoder::state
uint8_t state
Current state.
Definition: conv.h:84
len
static size_t len(const char *str)
n
write Write running configuration to or terminal n Write configuration to the copy running config startup Copy configuration n Copy running config to n Copy running config to startup write Write running configuration to or terminal n Write to terminal n
osmo_conv_encode_init
void osmo_conv_encode_init(struct osmo_conv_encoder *encoder, const struct osmo_conv_code *code)
Initialize a convolutional encoder.
Definition: conv.c:87
osmo_conv_decode_reset
void osmo_conv_decode_reset(struct osmo_conv_decoder *decoder, int start_state)
Definition: conv.c:276
osmo_conv_decoder::len
int len
Max o_idx (excl.
Definition: conv.h:110
osmo_conv_encoder
convolutional encoder state
Definition: conv.h:80
osmo_conv_decode_get_output
int osmo_conv_decode_get_output(struct osmo_conv_decoder *decoder, ubit_t *output, int has_flush, int end_state)
Definition: conv.c:533
osmo_conv_code::next_term_state
const uint8_t * next_term_state
Flush termination state
Definition: conv.h:63
osmo_conv_decoder::o_idx
int o_idx
output index
Definition: conv.h:112
osmo_conv_encode
int osmo_conv_encode(const struct osmo_conv_code *code, const ubit_t *input, ubit_t *output)
All-in-one convolutional encoding function.
Definition: conv.c:214
osmo_conv_decoder::code
const struct osmo_conv_code * code
for which code?
Definition: conv.h:106
osmo_conv_decoder::ae
unsigned int * ae
accumulated error
Definition: conv.h:115
osmo_conv_term
osmo_conv_term
possibe termination types
Definition: conv.h:40
sbit_t
int8_t sbit_t
soft bit with value (-127...127), as commonly used in communications receivers such as [viterbi] deco...
Definition: bits.h:21
bits.h
osmo_conv_code::next_output
const uint8_t(* next_output)[2]
Next output array.
Definition: conv.h:59
osmo_conv_decoder
convolutional decoder state
Definition: conv.h:105
osmo_conv_encode_load_state
void osmo_conv_encode_load_state(struct osmo_conv_encoder *encoder, const ubit_t *input)
Definition: conv.c:96
CONV_TERM_TAIL_BITING
@ CONV_TERM_TAIL_BITING
Tail biting.
Definition: conv.h:43
osmo_conv_get_output_length
int osmo_conv_get_output_length(const struct osmo_conv_code *code, int len)
Definition: conv.c:55
osmo_conv_encode_flush
int osmo_conv_encode_flush(struct osmo_conv_encoder *encoder, ubit_t *output)
Definition: conv.c:168
osmo_conv_decode_scan
int osmo_conv_decode_scan(struct osmo_conv_decoder *decoder, const sbit_t *input, int n)
Definition: conv.c:327
osmo_conv_decode_rewind
void osmo_conv_decode_rewind(struct osmo_conv_decoder *decoder)
Definition: conv.c:297
osmo_conv_decode
int osmo_conv_decode(const struct osmo_conv_code *code, const sbit_t *input, ubit_t *output)
All-in-one convolutional decoding function.
Definition: conv.c:609
osmo_conv_decode_flush
int osmo_conv_decode_flush(struct osmo_conv_decoder *decoder, const sbit_t *input)
Definition: conv.c:428
osmo_conv_code::next_state
const uint8_t(* next_state)[2]
Next state array
Definition: conv.h:60
osmo_conv_encoder::code
const struct osmo_conv_code * code
for which code?
Definition: conv.h:81
CONV_TERM_FLUSH
@ CONV_TERM_FLUSH
Flush encoder state.
Definition: conv.h:41
osmo_conv_code::K
int K
Constraint length.
Definition: conv.h:54
osmo_conv_decode_init
void osmo_conv_decode_init(struct osmo_conv_decoder *decoder, const struct osmo_conv_code *code, int len, int start_state)
Definition: conv.c:248
osmo_conv_get_input_length
int osmo_conv_get_input_length(const struct osmo_conv_code *code, int len)
Definition: conv.c:49
osmo_conv_code::puncture
const int * puncture
Punctured bits indexes.
Definition: conv.h:65
ubit_t
uint8_t ubit_t
unpacked bit (0 or 1): 1 bit per byte
Definition: bits.h:24
osmo_conv_code::N
int N
Inverse of code rate.
Definition: conv.h:53
osmo_conv_code::next_term_output
const uint8_t * next_term_output
Flush termination output.
Definition: conv.h:62
osmo_conv_encode_raw
int osmo_conv_encode_raw(struct osmo_conv_encoder *encoder, const ubit_t *input, ubit_t *output, int n)
Definition: conv.c:139
osmo_conv_code::len
int len
Definition: conv.h:55
osmo_conv_decoder::n_states
int n_states
number of states
Definition: conv.h:108
osmo_conv_decode_deinit
void osmo_conv_decode_deinit(struct osmo_conv_decoder *decoder)
Definition: conv.c:317
osmo_conv_code
structure describing a given convolutional code
Definition: conv.h:52