From 5785a4a8fc3c0c685e02b969ad07c1751502f0d5 Mon Sep 17 00:00:00 2001 From: Harald Welte Date: Wed, 13 May 2020 23:10:31 +0200 Subject: codec: Add functions for AMR s->d bits and d->s bits These functions implement re-ordering of bits as per TS 06.90 / 26.101 based on the already existing tables we've had in libosmocoding. Change-Id: Ia4ac2aea2e96f9185f082a07ca64dfc5276efb46 --- include/osmocom/codec/codec.h | 6 +++ src/codec/Makefile.am | 2 +- src/codec/gsm690.c | 110 ++++++++++++++++++++++++++++++++++++++++++ tests/codec/codec_test.c | 39 +++++++++++++++ tests/codec/codec_test.ok | 9 ++++ 5 files changed, 165 insertions(+), 1 deletion(-) diff --git a/include/osmocom/codec/codec.h b/include/osmocom/codec/codec.h index 6a1bf9fb..cbdad75e 100644 --- a/include/osmocom/codec/codec.h +++ b/include/osmocom/codec/codec.h @@ -6,6 +6,7 @@ #include #include +#include /* TS 101318 Chapter 5.1: 260 bits + 4bit sig */ #define GSM_FR_BYTES 33 @@ -51,6 +52,11 @@ enum osmo_amr_quality { AMR_GOOD = 1 }; +extern const uint8_t gsm690_bitlength[AMR_NO_DATA+1]; + +int osmo_amr_s_to_d(ubit_t *out, const ubit_t *in, uint16_t n_bits, enum osmo_amr_type amr_mode); +int osmo_amr_d_to_s(ubit_t *out, const ubit_t *in, uint16_t n_bits, enum osmo_amr_type amr_mode); + /*! Check if given AMR Frame Type is a speech frame * \param[in] ft AMR Frame Type * \returns true if AMR with given Frame Type contains voice, false otherwise diff --git a/src/codec/Makefile.am b/src/codec/Makefile.am index ac33aa01..778eb2ad 100644 --- a/src/codec/Makefile.am +++ b/src/codec/Makefile.am @@ -3,7 +3,7 @@ # before making any modifications: https://www.gnu.org/software/libtool/manual/html_node/Versioning.html LIBVERSION=2:0:2 -AM_CPPFLAGS = -I$(top_srcdir)/include $(TALLOC_CFLAGS) +AM_CPPFLAGS = -I$(top_srcdir)/include -I$(top_builddir)/include $(TALLOC_CFLAGS) AM_CFLAGS = -Wall if ENABLE_PSEUDOTALLOC diff --git a/src/codec/gsm690.c b/src/codec/gsm690.c index 8ab1df12..cc6cdf0c 100644 --- a/src/codec/gsm690.c +++ b/src/codec/gsm690.c @@ -2,6 +2,7 @@ * GSM 06.90 - GSM AMR Codec. */ /* * (C) 2010 Sylvain Munaut + * (C) 2020 Harald Welte * * All Rights Reserved * @@ -29,6 +30,7 @@ #include #include +#include #include /* * These table map between the raw encoder parameter output and @@ -216,6 +218,114 @@ const uint16_t gsm690_4_75_bitorder[95] = { 92, 31, 52, 65, 86, }; +/*! These constants refer to the length of one "AMR core frame" as per + * TS 26.101 Section 4.2.2 / Table 2. */ +const uint8_t gsm690_bitlength[AMR_NO_DATA+1] = { + [AMR_4_75] = 95, + [AMR_5_15] = 103, + [AMR_5_90] = 118, + [AMR_6_70] = 134, + [AMR_7_40] = 148, + [AMR_7_95] = 159, + [AMR_10_2] = 204, + [AMR_12_2] = 244, + [AMR_SID] = 39, +}; + +struct ts26101_reorder_table { + /*! Table as per TS 26.101 Annex B to compute d-bits from s-bits */ + const uint16_t *s_to_d; + /*! size of table */ + uint8_t len; +}; + +static const struct ts26101_reorder_table ts26101_reorder_tables[8] = { + [AMR_4_75] = { + .s_to_d = gsm690_4_75_bitorder, + .len = ARRAY_SIZE(gsm690_4_75_bitorder), + }, + [AMR_5_15] = { + .s_to_d = gsm690_5_15_bitorder, + .len = ARRAY_SIZE(gsm690_5_15_bitorder), + }, + [AMR_5_90] = { + .s_to_d = gsm690_5_9_bitorder, + .len = ARRAY_SIZE(gsm690_5_9_bitorder), + }, + [AMR_6_70] = { + .s_to_d = gsm690_6_7_bitorder, + .len = ARRAY_SIZE(gsm690_6_7_bitorder), + }, + [AMR_7_40] = { + .s_to_d = gsm690_7_4_bitorder, + .len = ARRAY_SIZE(gsm690_7_4_bitorder), + }, + [AMR_7_95] = { + .s_to_d = gsm690_7_95_bitorder, + .len = ARRAY_SIZE(gsm690_7_95_bitorder), + }, + [AMR_10_2] = { + .s_to_d = gsm690_10_2_bitorder, + .len = ARRAY_SIZE(gsm690_10_2_bitorder), + }, + [AMR_12_2] = { + .s_to_d = gsm690_12_2_bitorder, + .len = ARRAY_SIZE(gsm690_12_2_bitorder), + }, +}; + +/*! Convert from S-bits (codec output) to d-bits. + * \param[out] out user-provided output buffer for generated unpacked d-bits + * \param[in] in input buffer for unpacked s-bits + * \param[in] n_bits number of bits (in both in and out) + * \param[in] AMR mode (0..7) */ +int osmo_amr_s_to_d(ubit_t *out, const ubit_t *in, uint16_t n_bits, enum osmo_amr_type amr_mode) +{ + const struct ts26101_reorder_table *tbl; + int i; + + if (amr_mode >= ARRAY_SIZE(ts26101_reorder_tables)) + return -ENODEV; + + tbl = &ts26101_reorder_tables[amr_mode]; + + if (n_bits > tbl->len) + return -EINVAL; + + for (i = 0; i < n_bits; i++) { + uint16_t n = tbl->s_to_d[i]; + out[i] = in[n]; + } + + return n_bits; +} + +/*! Convert from d-bits to s-bits (codec input). + * \param[out] out user-provided output buffer for generated unpacked s-bits + * \param[in] in input buffer for unpacked d-bits + * \param[in] n_bits number of bits (in both in and out) + * \param[in] AMR mode (0..7) */ +int osmo_amr_d_to_s(ubit_t *out, const ubit_t *in, uint16_t n_bits, enum osmo_amr_type amr_mode) +{ + const struct ts26101_reorder_table *tbl; + int i; + + if (amr_mode >= ARRAY_SIZE(ts26101_reorder_tables)) + return -ENODEV; + + tbl = &ts26101_reorder_tables[amr_mode]; + + if (n_bits > tbl->len) + return -EINVAL; + + for (i = 0; i < n_bits; i++) { + uint16_t n = tbl->s_to_d[i]; + out[n] = in[i]; + } + + return n_bits; +} + /* See also RFC 4867 ยง3.6, Table 1, Column "Total speech bits" */ static const uint8_t amr_len_by_ft[16] = { 12, 13, 15, 17, 19, 20, 26, 31, 5, 0, 0, 0, 0, 0, 0, 0 diff --git a/tests/codec/codec_test.c b/tests/codec/codec_test.c index 7a10fc57..5579e996 100644 --- a/tests/codec/codec_test.c +++ b/tests/codec/codec_test.c @@ -190,6 +190,42 @@ static void test_sid_fr(void) } } + + +static void test_amr_s_d(void) +{ + ubit_t in[244]; + ubit_t mid[244]; + ubit_t out[244]; + int i, j; + + for (j = AMR_4_75; j <= AMR_12_2; j++) { + unsigned int n_bits = gsm690_bitlength[j]; + + printf("=> AMR Mode %d (%d bits)\n", j, n_bits); + /* set a single bit in the input buffer */ + for (i = 0; i < n_bits; i++) { + + memset(in, 0, sizeof(in)); + in[i] = 1; + + /* re-order from s to d */ + osmo_amr_s_to_d(mid, in, n_bits, j); + + /* and back to d */ + osmo_amr_d_to_s(out, mid, n_bits, j); + + if (memcmp(in, out, n_bits)) { + printf("Error in bit %d of mode %d!\n", i, j); + printf("inp s-bits: %s\n", osmo_ubit_dump(in, n_bits)); + printf("mid d-bits: %s\n", osmo_ubit_dump(mid, n_bits)); + printf("out s-bits: %s\n", osmo_ubit_dump(out, n_bits)); + //OSMO_ASSERT(0); + } + } + } +} + int main(int argc, char **argv) { printf("AMR RTP payload decoder test:\n"); @@ -213,6 +249,9 @@ int main(int argc, char **argv) printf("FR RTP payload SID test:\n"); test_sid_fr(); + printf("AMR s/d bit re-ordering test:\n"); + test_amr_s_d(); + return 0; } diff --git a/tests/codec/codec_test.ok b/tests/codec/codec_test.ok index b8cba19c..7d8609ba 100644 --- a/tests/codec/codec_test.ok +++ b/tests/codec/codec_test.ok @@ -30,3 +30,12 @@ FR SID d9 23 ba e5 e2 00 00 80 41 20 00 01 00 00 10 00 04 00 00 00 00 00 48 00 0 FR SID d8 62 a2 61 60 00 00 10 00 00 92 00 00 00 00 40 00 00 08 00 00 00 01 00 00 01 00 00 80 00 40 02 40 : 1 FR SID d9 e4 c3 6d 12 00 00 80 00 20 00 40 00 00 00 00 00 10 00 00 00 10 48 00 10 48 00 00 00 00 2d 04 00 : 1 FR SID d9 a4 c3 29 59 00 00 10 00 00 12 00 00 00 00 41 00 00 01 00 00 00 01 00 80 00 00 00 00 42 00 12 02 : 1 +AMR s/d bit re-ordering test: +=> AMR Mode 0 (95 bits) +=> AMR Mode 1 (103 bits) +=> AMR Mode 2 (118 bits) +=> AMR Mode 3 (134 bits) +=> AMR Mode 4 (148 bits) +=> AMR Mode 5 (159 bits) +=> AMR Mode 6 (204 bits) +=> AMR Mode 7 (244 bits) -- cgit v1.2.3