laforge has uploaded this change for review. (
https://gerrit.osmocom.org/c/libosmo-abis/+/18382 )
Change subject: WIP: TRAU frame RTP conversion
......................................................................
WIP: TRAU frame RTP conversion
This adds code that converts codec frames between (decoded) TRAU format
and RTP payload format. The FR + EFR functions have been lifted from
OsmoNITB.
Change-Id: I7f6993cce2b95318203043e2e14952e581941b79
---
M src/Makefile.am
A src/trau/trau_rtp_conv.c
2 files changed, 483 insertions(+), 1 deletion(-)
git pull ssh://gerrit.osmocom.org:29418/libosmo-abis refs/changes/82/18382/1
diff --git a/src/Makefile.am b/src/Makefile.am
index 0134b00..4254428 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -37,6 +37,7 @@
libosmotrau_la_LIBADD = $(COMMONLIBS) $(ORTP_LIBS)
libosmotrau_la_SOURCES = trau/osmo_ortp.c \
trau/trau_frame.c \
- trau/trau_sync.c
+ trau/trau_sync.c \
+ trau/trau_rtp_conv.c
noinst_HEADERS = trau/ubit_buf.h
diff --git a/src/trau/trau_rtp_conv.c b/src/trau/trau_rtp_conv.c
new file mode 100644
index 0000000..c3007ad
--- /dev/null
+++ b/src/trau/trau_rtp_conv.c
@@ -0,0 +1,481 @@
+/* TRAU frame to RTP conversion */
+
+/* (C) 2009,2020 by Harald Welte <lafo...@gnumonks.org>
+ * All Rights Reserved
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <osmocom/core/crc8gen.h>
+#include <osmocom/codec/codec.h>
+
+#include <osmocom/trau/trau_frame.h>
+
+/* this corresponds to the bit-lengths of the individual codec
+ * parameters as indicated in Table 1.1 of TS 46.010 */
+static const uint8_t gsm_fr_map[] = {
+ 6, 6, 5, 5, 4, 4, 3, 3,
+ 7, 2, 2, 6, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 7, 2, 2, 6, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 7, 2, 2, 6, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 7, 2, 2, 6, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3
+};
+
+
+/*
+ * EFR TRAU parity
+ *
+ * g(x) = x^3 + x^1 + 1
+ */
+static const struct osmo_crc8gen_code gsm0860_efr_crc3 = {
+ .bits = 3,
+ .poly = 0x3,
+ .init = 0x0,
+ .remainder = 0x7,
+};
+
+/* re-combine EFR parity bits */
+static inline void efr_parity_bits_1(ubit_t *check_bits, const ubit_t *d_bits)
+{
+ memcpy(check_bits + 0 , d_bits + 0, 22);
+ memcpy(check_bits + 22 , d_bits + 24, 3);
+ check_bits[25] = d_bits[28];
+}
+
+static inline void efr_parity_bits_2(ubit_t *check_bits, const ubit_t *d_bits)
+{
+ memcpy(check_bits + 0 , d_bits + 42, 10);
+ memcpy(check_bits + 10 , d_bits + 90, 2);
+}
+
+static inline void efr_parity_bits_3(ubit_t *check_bits, const ubit_t *d_bits)
+{
+ memcpy(check_bits + 0 , d_bits + 98, 5);
+ check_bits[5] = d_bits[104];
+ memcpy(check_bits + 6 , d_bits + 143, 2);
+}
+
+static inline void efr_parity_bits_4(ubit_t *check_bits, const ubit_t *d_bits)
+{
+ memcpy(check_bits + 0 , d_bits + 151, 10);
+ memcpy(check_bits + 10 , d_bits + 199, 2);
+}
+
+static inline void efr_parity_bits_5(ubit_t *check_bits, const ubit_t *d_bits)
+{
+ memcpy(check_bits + 0 , d_bits + 207, 5);
+ check_bits[5] = d_bits[213];
+ memcpy(check_bits + 6 , d_bits + 252, 2);
+}
+
+//static const uint8_t c_bits_check_fr[] = { 0, 0, 0, 1, 0 };
+//static const uint8_t c_bits_check_efr[] = { 1, 1, 0, 1, 0 };
+
+/*! Generate the 33 bytes RTP payload for GSM-FR from a decoded TRAU frame.
+ * \param[out] out caller-provided output buffer
+ * \param[in] out_len length of out buffer in bytes
+ * \param[in] fr input TRAU frame in decoded form
+ * \returns number of bytes generated in 'out'; negative on error. */
+int trau2rtp_fr(uint8_t *out, size_t out_len, const struct osmo_trau_frame *tf)
+{
+ int i, j, k, l, o;
+
+ if (tf->type != OSMO_TRAU16_FT_FR)
+ return -EINVAL;
+
+ /* FR Data Bits according to TS 48.060 Section 5.5.1.1.2 */
+
+ if (tf->c_bits[11]) /* BFI */
+ return 0;
+
+ if (out_len < GSM_FR_BYTES)
+ return -ENOSPC;
+
+ out[0] = 0xd << 4;
+ /* reassemble d-bits */
+ i = 0; /* counts bits */
+ j = 4; /* counts output bits */
+ k = gsm_fr_map[0]-1; /* current number bit in element */
+ l = 0; /* counts element bits */
+ o = 0; /* offset input bits */
+ while (i < 260) {
+ out[j/8] |= (tf->d_bits[k+o] << (7-(j%8)));
+ /* to avoid out-of-bounds access in gsm_fr_map[++l] */
+ if (i == 259)
+ break;
+ if (--k < 0) {
+ o += gsm_fr_map[l];
+ k = gsm_fr_map[++l]-1;
+ }
+ i++;
+ j++;
+ }
+
+ return GSM_FR_BYTES;
+}
+
+/*! Generate the 31 bytes RTP payload for GSM-EFR from a decoded TRAU frame.
+ * \param[out] out caller-provided output buffer
+ * \param[in] out_len length of out buffer in bytes
+ * \param[in] fr input TRAU frame in decoded form
+ * \returns number of bytes generated in 'out'; negative on error. */
+int trau2rtp_efr(uint8_t *out, size_t out_len, const struct osmo_trau_frame
*tf)
+{
+ int i, j, rc;
+ ubit_t check_bits[26];
+
+ if (tf->type != OSMO_TRAU16_FT_EFR)
+ return -EINVAL;
+
+ /* FR Data Bits according to TS 48.060 Section 5.5.1.1.2 */
+
+ if (tf->c_bits[11]) /* BFI */
+ return 0;
+
+ if (out_len < GSM_EFR_BYTES)
+ return -ENOSPC;
+
+ if (tf->c_bits[11]) /* BFI */
+ goto bad_frame;
+
+ out[0] = 0xc << 4;
+ /* reassemble d-bits */
+ for (i = 1, j = 4; i < 39; i++, j++)
+ out[j/8] |= (tf->d_bits[i] << (7-(j%8)));
+ efr_parity_bits_1(check_bits, tf->d_bits);
+ rc = osmo_crc8gen_check_bits(&gsm0860_efr_crc3, check_bits, 26,
+ tf->d_bits + 39);
+ if (rc)
+ goto bad_frame;
+ for (i = 42, j = 42; i < 95; i++, j++)
+ out[j/8] |= (tf->d_bits[i] << (7-(j%8)));
+ efr_parity_bits_2(check_bits, tf->d_bits);
+ rc = osmo_crc8gen_check_bits(&gsm0860_efr_crc3, check_bits, 12,
+ tf->d_bits + 95);
+ if (rc)
+ goto bad_frame;
+ for (i = 98, j = 95; i < 148; i++, j++)
+ out[j/8] |= (tf->d_bits[i] << (7-(j%8)));
+ efr_parity_bits_3(check_bits, tf->d_bits);
+ rc = osmo_crc8gen_check_bits(&gsm0860_efr_crc3, check_bits, 8,
+ tf->d_bits + 148);
+ if (rc)
+ goto bad_frame;
+ for (i = 151, j = 145; i < 204; i++, j++)
+ out[j/8] |= (tf->d_bits[i] << (7-(j%8)));
+ efr_parity_bits_4(check_bits, tf->d_bits);
+ rc = osmo_crc8gen_check_bits(&gsm0860_efr_crc3, check_bits, 12,
+ tf->d_bits + 204);
+ if (rc)
+ goto bad_frame;
+ for (i = 207, j = 198; i < 257; i++, j++)
+ out[j/8] |= (tf->d_bits[i] << (7-(j%8)));
+ efr_parity_bits_5(check_bits, tf->d_bits);
+ rc = osmo_crc8gen_check_bits(&gsm0860_efr_crc3, check_bits, 8,
+ tf->d_bits + 257);
+ if (rc)
+ goto bad_frame;
+
+ return GSM_EFR_BYTES;
+bad_frame:
+ return 0;
+}
+
+/* TS 48.060 Section 5.5.1.1.2 */
+int rtp2trau_fr(struct osmo_trau_frame *tf, const uint8_t *data, size_t
data_len)
+{
+ int i, j, k, l, o;
+
+ /* TODO: consider data_len == 0 for SID frame? */
+ if (data_len < GSM_FR_BYTES)
+ return -EINVAL;
+
+ if (data[0] >> 4 != 0xd)
+ return -EINVAL;
+
+ tf->type = OSMO_TRAU16_FT_FR;
+
+ /* FR Data Bits according to TS 48.060 Section 5.5.1.1.2 */
+
+ /* FIXME: Generate SID frames? */
+ /* FIXME: Generate BFI frames? */
+
+ /* set c-bits and t-bits */
+ tf->c_bits[0] = 1;
+ tf->c_bits[1] = 1;
+ tf->c_bits[2] = 1;
+ tf->c_bits[3] = 0;
+ tf->c_bits[4] = 0;
+ memset(&tf->c_bits[5], 0, 6);
+ memset(&tf->c_bits[11], 1, 10);
+ memset(&tf->t_bits[0], 1, 4);
+ /* reassemble d-bits */
+ i = 0; /* counts bits */
+ j = 4; /* counts input bits */
+ k = gsm_fr_map[0]-1; /* current number bit in element */
+ l = 0; /* counts element bits */
+ o = 0; /* offset output bits */
+ while (i < 260) {
+ tf->d_bits[k+o] = (data[j/8] >> (7-(j%8))) & 1;
+ /* to avoid out-of-bounds access in gsm_fr_map[++l] */
+ if (i == 259)
+ break;
+ if (--k < 0) {
+ o += gsm_fr_map[l];
+ k = gsm_fr_map[++l]-1;
+ }
+ i++;
+ j++;
+ }
+
+ return 0;
+}
+
+/* TS 48.060 Section 5.5.1.1.2 */
+int rtp2trau_efr(struct osmo_trau_frame *tf, const uint8_t *data, size_t
data_len)
+{
+ int i, j;
+ ubit_t check_bits[26];
+
+ /* TODO: consider data_len == 0 for SID frame? */
+ if (data_len < GSM_EFR_BYTES)
+ return -EINVAL;
+
+ if (data[0] >> 4 != 0xc)
+ return -EINVAL;
+
+ tf->type = OSMO_TRAU16_FT_EFR;
+
+ /* FR Data Bits according to TS 48.060 Section 5.5.1.1.2 */
+
+ /* FIXME: Generate SID frames? */
+ /* FIXME: Generate BFI frames? */
+
+ /* set c-bits and t-bits */
+ tf->c_bits[0] = 1;
+ tf->c_bits[1] = 1;
+ tf->c_bits[2] = 0;
+ tf->c_bits[3] = 1;
+ tf->c_bits[4] = 0;
+ memset(&tf->c_bits[5], 0, 6);
+ memset(&tf->c_bits[11], 1, 10);
+ memset(&tf->t_bits[0], 1, 4);
+ /* reassemble d-bits */
+ tf->d_bits[0] = 1;
+ for (i = 1, j = 4; i < 39; i++, j++)
+ tf->d_bits[i] = (data[j/8] >> (7-(j%8))) & 1;
+ efr_parity_bits_1(check_bits, tf->d_bits);
+ osmo_crc8gen_set_bits(&gsm0860_efr_crc3, check_bits, 26,
+ tf->d_bits + 39);
+ for (i = 42, j = 42; i < 95; i++, j++)
+ tf->d_bits[i] = (data[j/8] >> (7-(j%8))) & 1;
+ efr_parity_bits_2(check_bits, tf->d_bits);
+ osmo_crc8gen_set_bits(&gsm0860_efr_crc3, check_bits, 12,
+ tf->d_bits + 95);
+ for (i = 98, j = 95; i < 148; i++, j++)
+ tf->d_bits[i] = (data[j/8] >> (7-(j%8))) & 1;
+ efr_parity_bits_3(check_bits, tf->d_bits);
+ osmo_crc8gen_set_bits(&gsm0860_efr_crc3, check_bits, 8,
+ tf->d_bits + 148);
+ for (i = 151, j = 145; i < 204; i++, j++)
+ tf->d_bits[i] = (data[j/8] >> (7-(j%8))) & 1;
+ efr_parity_bits_4(check_bits, tf->d_bits);
+ osmo_crc8gen_set_bits(&gsm0860_efr_crc3, check_bits, 12,
+ tf->d_bits + 204);
+ for (i = 207, j = 198; i < 257; i++, j++)
+ tf->d_bits[i] = (data[j/8] >> (7-(j%8))) & 1;
+ efr_parity_bits_5(check_bits, tf->d_bits);
+ osmo_crc8gen_set_bits(&gsm0860_efr_crc3, check_bits, 8,
+ tf->d_bits + 257);
+
+ return 0;
+}
+
+#if 0
+static inline memcpy_inc(uint8_t *out, const uint8_t *in, size_t len, unsigned
int *idx)
+{
+ memcpy_inc(out, in, len);
+ *idx += len;
+}
+
+static int amr_speech_extract_sbits(ubit_t *s_bits, const struct
osmo_trau_frame *tf,
+ enum osmo_amr_mode mode)
+{
+ unsigned int s_idx = 0;
+
+ switch (mode) {
+ case AMR_4_75:
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 44, 67 - 44, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 67, 92 - 67, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 95, 108 - 95, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 111, 132 - 111, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 135, 148 - 135, &s_idx);
+ break;
+ case AMR_5_15:
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 46, 96 - 46, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 69, 92 - 69, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 95, 114 - 95, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 117, 136 - 117, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 139, 158 - 139, &s_idx);
+ break;
+ case AMR_5_90:
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 41, 67 - 41, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 67, 92 - 67, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 95, 116 - 95, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 119, 144 - 119, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 147, 168 - 147, &s_idx);
+ break;
+ case AMR_6_70:
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 37, 63 - 37, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 63, 92 - 63, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 95, 120 - 95, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 123, 152 - 123, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 155, 180 - 155, &s_idx);
+ break;
+ case AMR_7_40:
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 34, 60 - 34, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 60, 92 - 60, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 95, 124 - 95, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 127, 159 - 127, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 162, 191 - 162, &s_idx);
+ break;
+ case AMR_7_95:
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 31, 58 - 31, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 58, 92 - 58, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 95, 127 - 95, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 130, 164 - 130, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 167, 199 - 167, &s_idx);
+ break;
+ case AMR_10_2:
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 20, 46 - 20, &s_idx);
/* D21..D46 */
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 46, 92 - 46, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 95, 138 - 95, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 141, 187 - 141, &s_idx);
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 190, 233 - 190, &s_idx);
+ break;
+ case AMR_12_2:
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 0, 38 - 0, &s_idx);
/* D1..D38 */
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 38, 91 - 38, &s_idx);
/* D39..D91 */
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 94, 144 - 94, &s_idx);
/* D95..D144 */
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 147, 200 - 147,
&s_idx);/* D148..D200 */
+ memcpy_inc(s_bits + s_idx, tf->d_bits + 203, 253 - 203,
&s_idx);/* D204..D253 */
+ break;
+ }
+
+ return s_idx;
+}
+
+/* TS 48.060 Section 5.5.1.2.2 */
+static int trau2rtp_16(uint8_t *out, const struct osmo_trau_frame *tf, enum
osmo_amr_mode last_cmi)
+{
+ enum osmo_amr_mode mode = last_cmi;
+ uint8_t frame_class = tf->c_bits[21] << 1 | tf->c_bits[20];
+ uint8_t cmr_cmi = tf->c_bits[23] << 2 | tf->c_bits[24] << 1 |
tf->cb_bits[25];
+ uint8_t no_speech_cls;
+ uint8_t s_bits[242];
+ uint8_t d_bits[242];
+ unsigned int s_idx = 0;
+ ubit_t rif = FIXME;
+
+ if (tf->type != OSMO_TRAU16_FT_AMR)
+ return -EINVAL;
+
+ if (rif == 0)
+ mode = cmr_cmi;
+
+ switch (frame_class) {
+ case 0: // no speech
+ no_speech_cls = tf->d_bits[32] << 2 | tf->d_bits[33] << 1 |
tf->d_bits[34];
+ cmi_abs = tf->d_bits[35] << 2 | tf->d_bits[36] < 1 ||
tf->d_bits[37];
+ cmr_abs = tf->d_bits[38] << 2 | tf->d_bits[39] < 1 ||
tf->d_bits[40];
+ switch (no_speech_cls) {
+ case 7: // sid first
+ break;
+ case 6: // onset
+ break;
+ case 5: // sid_update
+ break;
+ case 4: // sid_bad
+ break;
+ case 0: // no_data
+ break;
+ }
+ break;
+ case 1: // speech bad
+ break;
+ case 2:
+ case 3:
+ /* Extract the s-bits from the TRAU frame */
+ amr_speech_extract_sbits(s_bits, tf, mode);
+ /* Convert the s-bits to d-bits */
+ osmo_amr_s_to_d(d_bits, s_bits, mode);
+ break;
+ }
+}
+
+int trau2rtp_amr(uint8_t *out, const struct osmo_trau_frame *tf, enum
osmo_amr_mode last_cmi))
+{
+ switch (tf->type) {
+ case OSMO_TRAU16_FT_AMR:
+ return trau2rtp_16(out, tf, last_cmi);
+ case OSMO_TRAU8_AMR_LOW:
+ case OSMO_TRAU8_AMR_6k7:
+ case OSMO_TRAU8_AMR_7k4:
+ default:
+ return -EINVAL;
+ }
+}
+#endif
+
+struct osmo_trau2rtp_state {
+ enum osmo_trau_frame_type type;
+};
+
+int osmo_trau2rtp(uint8_t *out, size_t out_len, const struct osmo_trau_frame
*tf,
+ struct osmo_trau2rtp_state *st)
+{
+ switch (tf->type) {
+ case OSMO_TRAU16_FT_FR:
+ return trau2rtp_fr(out, out_len, tf);
+ case OSMO_TRAU16_FT_EFR:
+ return trau2rtp_efr(out, out_len, tf);
+ default:
+ return -EINVAL;
+ }
+}
+
+int osmo_rtp2trau(struct osmo_trau_frame *tf, const uint8_t *rtp, size_t
rtp_len,
+ struct osmo_trau2rtp_state *st)
+{
+ switch (st->type) {
+ case OSMO_TRAU16_FT_FR:
+ return rtp2trau_fr(tf, rtp, rtp_len);
+ case OSMO_TRAU16_FT_EFR:
+ return rtp2trau_efr(tf, rtp, rtp_len);
+ default:
+ return -EINVAL;
+ }
+}
--
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Gerrit-Project: libosmo-abis
Gerrit-Branch: master
Gerrit-Change-Id: I7f6993cce2b95318203043e2e14952e581941b79
Gerrit-Change-Number: 18382
Gerrit-PatchSet: 1
Gerrit-Owner: laforge <lafo...@osmocom.org>
Gerrit-MessageType: newchange
