[pulseaudio-discuss] [PATCH v15 08/10] bluetooth: Add A2DP aptX and aptX HD codecs support
Pali Rohár
pali.rohar at gmail.com
Wed Apr 15 19:04:44 UTC 2020
This patch provides support for aptX and aptX HD codecs in bluetooth A2DP
profile. It uses open source LGPLv2.1+ licensed libopenaptx library which
can be found at https://github.com/pali/libopenaptx.
aptX for s24 stereo samples provides fixed 6:1 compression ratio and
bitrate 352.8 kbit/s, aptX HD provides fixed 4:1 compression ratio and
bitrate 529.2 kbit/s.
According to soundexpert research, aptX codec used in bluetooth A2DP is no
better than SBC High Quality settings. And you cannot hear difference
between aptX and SBC High Quality, aptX is just a copper-less overpriced
audio cable.
aptX HD is high-bitrate version of aptX. It has clearly noticeable increase
in sound quality (not dramatic though taking into account the increase in
bitrate).
http://soundexpert.org/news/-/blogs/audio-quality-of-bluetooth-aptx
---
configure.ac | 36 ++
src/Makefile.am | 6 +
src/modules/bluetooth/a2dp-codec-aptx.c | 522 ++++++++++++++++++++++++
src/modules/bluetooth/a2dp-codec-util.c | 8 +
4 files changed, 572 insertions(+)
create mode 100644 src/modules/bluetooth/a2dp-codec-aptx.c
diff --git a/configure.ac b/configure.ac
index fa93172b7..2dc9b61ad 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1118,6 +1118,40 @@ AC_SUBST(HAVE_BLUEZ_5_NATIVE_HEADSET)
AM_CONDITIONAL([HAVE_BLUEZ_5_NATIVE_HEADSET], [test "x$HAVE_BLUEZ_5_NATIVE_HEADSET" = x1])
AS_IF([test "x$HAVE_BLUEZ_5_NATIVE_HEADSET" = "x1"], AC_DEFINE([HAVE_BLUEZ_5_NATIVE_HEADSET], 1, [Bluez 5 native headset backend enabled]))
+#### Bluetooth A2DP aptX codec (optional) ###
+
+AC_ARG_ENABLE([aptx],
+ AS_HELP_STRING([--disable-aptx],[Disable optional bluetooth A2DP aptX and aptX HD codecs support (via libopenaptx)]))
+AC_ARG_VAR([OPENAPTX_CPPFLAGS], [C preprocessor flags for openaptx])
+AC_ARG_VAR([OPENAPTX_LDFLAGS], [linker flags for openaptx])
+
+CPPFLAGS_SAVE="$CPPFLAGS"
+LDFLAGS_SAVE="$LDFLAGS"
+LIBS_SAVE="$LIBS"
+
+CPPFLAGS="$CPPFLAGS $OPENAPTX_CPPFLAGS"
+LDFLAGS="$LDFLAGS $OPENAPTX_LDFLAGS"
+
+AS_IF([test "x$HAVE_BLUEZ_5" = "x1" && test "x$enable_aptx" != "xno"],
+ [AC_CHECK_HEADER([openaptx.h],
+ [AC_SEARCH_LIBS([aptx_init], [openaptx],
+ [HAVE_OPENAPTX=1; AS_IF([test "x$ac_cv_search_aptx_init" != "xnone required"], [OPENAPTX_LDFLAGS="$OPENAPTX_LDFLAGS $ac_cv_search_aptx_init"])],
+ [HAVE_OPENAPTX=0])],
+ [HAVE_OPENAPTX=0])])
+
+CPPFLAGS="$CPPFLAGS_SAVE"
+LDFLAGS="$LDFLAGS_SAVE"
+LIBS="$LIBS_SAVE"
+
+AS_IF([test "x$HAVE_BLUEZ_5" = "x1" && test "x$enable_aptx" = "xyes" && test "x$HAVE_OPENAPTX" = "x0"],
+ [AC_MSG_ERROR([*** libopenaptx from https://github.com/pali/libopenaptx not found])])
+
+AC_SUBST(OPENAPTX_CPPFLAGS)
+AC_SUBST(OPENAPTX_LDFLAGS)
+AC_SUBST(HAVE_OPENAPTX)
+AM_CONDITIONAL([HAVE_OPENAPTX], [test "x$HAVE_OPENAPTX" = "x1"])
+AS_IF([test "x$HAVE_OPENAPTX" = "x1"], AC_DEFINE([HAVE_OPENAPTX], 1, [Have openaptx codec library]))
+
#### UDEV support (optional) ####
AC_ARG_ENABLE([udev],
@@ -1619,6 +1653,7 @@ AS_IF([test "x$HAVE_SYSTEMD_JOURNAL" = "x1"], ENABLE_SYSTEMD_JOURNAL=yes, ENABLE
AS_IF([test "x$HAVE_BLUEZ_5" = "x1"], ENABLE_BLUEZ_5=yes, ENABLE_BLUEZ_5=no)
AS_IF([test "x$HAVE_BLUEZ_5_OFONO_HEADSET" = "x1"], ENABLE_BLUEZ_5_OFONO_HEADSET=yes, ENABLE_BLUEZ_5_OFONO_HEADSET=no)
AS_IF([test "x$HAVE_BLUEZ_5_NATIVE_HEADSET" = "x1"], ENABLE_BLUEZ_5_NATIVE_HEADSET=yes, ENABLE_BLUEZ_5_NATIVE_HEADSET=no)
+AS_IF([test "x$HAVE_OPENAPTX" = "x1"], ENABLE_APTX=yes, ENABLE_APTX=no)
AS_IF([test "x$HAVE_HAL_COMPAT" = "x1"], ENABLE_HAL_COMPAT=yes, ENABLE_HAL_COMPAT=no)
AS_IF([test "x$HAVE_TCPWRAP" = "x1"], ENABLE_TCPWRAP=yes, ENABLE_TCPWRAP=no)
AS_IF([test "x$HAVE_LIBSAMPLERATE" = "x1"], ENABLE_LIBSAMPLERATE="yes (DEPRECATED)", ENABLE_LIBSAMPLERATE=no)
@@ -1678,6 +1713,7 @@ echo "
Enable BlueZ 5: ${ENABLE_BLUEZ_5}
Enable ofono headsets: ${ENABLE_BLUEZ_5_OFONO_HEADSET}
Enable native headsets: ${ENABLE_BLUEZ_5_NATIVE_HEADSET}
+ Enable aptX+aptXHD codecs: ${ENABLE_APTX}
Enable udev: ${ENABLE_UDEV}
Enable HAL->udev compat: ${ENABLE_HAL_COMPAT}
Enable systemd
diff --git a/src/Makefile.am b/src/Makefile.am
index 0f1ded7f9..0842a7bd5 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -2172,6 +2172,12 @@ libbluez5_util_la_SOURCES += modules/bluetooth/a2dp-codec-sbc.c
libbluez5_util_la_LIBADD += $(SBC_LIBS)
libbluez5_util_la_CFLAGS += $(SBC_CFLAGS)
+if HAVE_OPENAPTX
+libbluez5_util_la_SOURCES += modules/bluetooth/a2dp-codec-aptx.c
+libbluez5_util_la_CPPFLAGS += $(OPENAPTX_CPPFLAGS)
+libbluez5_util_la_LDFLAGS += $(OPENAPTX_LDFLAGS)
+endif
+
module_bluez5_discover_la_SOURCES = modules/bluetooth/module-bluez5-discover.c
module_bluez5_discover_la_LDFLAGS = $(MODULE_LDFLAGS)
module_bluez5_discover_la_LIBADD = $(MODULE_LIBADD) $(DBUS_LIBS) libbluez5-util.la
diff --git a/src/modules/bluetooth/a2dp-codec-aptx.c b/src/modules/bluetooth/a2dp-codec-aptx.c
new file mode 100644
index 000000000..2d911d902
--- /dev/null
+++ b/src/modules/bluetooth/a2dp-codec-aptx.c
@@ -0,0 +1,522 @@
+/***
+ This file is part of PulseAudio.
+
+ Copyright 2018-2019 Pali Rohár <pali.rohar at gmail.com>
+
+ PulseAudio is free software; you can redistribute it and/or modify
+ it under the terms of the GNU Lesser General Public License as
+ published by the Free Software Foundation; either version 2.1 of the
+ License, or (at your option) any later version.
+
+ PulseAudio 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 Lesser General Public
+ License along with PulseAudio; if not, see <http://www.gnu.org/licenses/>.
+***/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <pulsecore/log.h>
+#include <pulsecore/macro.h>
+#include <pulsecore/once.h>
+#include <pulse/sample.h>
+
+#include <arpa/inet.h>
+
+#include <openaptx.h>
+
+#include "a2dp-codecs.h"
+#include "a2dp-codec-api.h"
+#include "rtp.h"
+
+struct aptx_hd_info {
+ struct aptx_context *aptx_c;
+ uint16_t seq_num;
+};
+
+static bool can_accept_capabilities_common(const a2dp_aptx_t *capabilities, uint32_t vendor_id, uint16_t codec_id) {
+ if (A2DP_GET_VENDOR_ID(capabilities->info) != vendor_id || A2DP_GET_CODEC_ID(capabilities->info) != codec_id)
+ return false;
+
+ if (!(capabilities->frequency & (APTX_SAMPLING_FREQ_16000 | APTX_SAMPLING_FREQ_32000 |
+ APTX_SAMPLING_FREQ_44100 | APTX_SAMPLING_FREQ_48000)))
+ return false;
+
+ if (!(capabilities->channel_mode & APTX_CHANNEL_MODE_STEREO))
+ return false;
+
+ return true;
+}
+
+static bool can_accept_capabilities(const uint8_t *capabilities_buffer, uint8_t capabilities_size, bool for_encoding) {
+ const a2dp_aptx_t *capabilities = (const a2dp_aptx_t *) capabilities_buffer;
+
+ if (capabilities_size != sizeof(*capabilities))
+ return false;
+
+ return can_accept_capabilities_common(capabilities, APTX_VENDOR_ID, APTX_CODEC_ID);
+}
+
+static bool can_accept_capabilities_hd(const uint8_t *capabilities_buffer, uint8_t capabilities_size, bool for_encoding) {
+ const a2dp_aptx_hd_t *capabilities = (const a2dp_aptx_hd_t *) capabilities_buffer;
+
+ if (capabilities_size != sizeof(*capabilities))
+ return false;
+
+ return can_accept_capabilities_common(&capabilities->aptx, APTX_HD_VENDOR_ID, APTX_HD_CODEC_ID);
+}
+
+static int cmp_endpoints_common(const a2dp_aptx_t *capabilities1, const a2dp_aptx_t *capabilities2, const pa_sample_spec *default_sample_spec, bool for_encoding) {
+ uint32_t freq1 = 0;
+ uint32_t freq2 = 0;
+ int i;
+
+ static const struct {
+ uint32_t rate;
+ uint8_t cap;
+ } freq_table[] = {
+ { 16000U, APTX_SAMPLING_FREQ_16000 },
+ { 32000U, APTX_SAMPLING_FREQ_32000 },
+ { 44100U, APTX_SAMPLING_FREQ_44100 },
+ { 48000U, APTX_SAMPLING_FREQ_48000 }
+ };
+
+ /* Find the lowest freq that is at least as high as the requested sampling rate */
+ for (i = 0; (unsigned)i < PA_ELEMENTSOF(freq_table); i++) {
+ if (!freq1 && freq_table[i].rate >= default_sample_spec->rate && (capabilities1->frequency & freq_table[i].cap))
+ freq1 = freq_table[i].rate;
+ if (!freq2 && freq_table[i].rate >= default_sample_spec->rate && (capabilities2->frequency & freq_table[i].cap))
+ freq2 = freq_table[i].rate;
+ if (freq1 && freq2)
+ break;
+ }
+
+ /* Prefer endpoint which frequency is near to default sample rate */
+ if (freq1 && freq2) {
+ if (freq1 < freq2)
+ return -1;
+ if (freq1 > freq2)
+ return 1;
+ } else if (freq1) {
+ return freq1;
+ } else if (freq2) {
+ return freq2;
+ } else {
+ for (i = PA_ELEMENTSOF(freq_table)-1; i >= 0; i--) {
+ if (capabilities1->frequency & freq_table[i].cap)
+ freq1 = freq_table[i].rate;
+ if (capabilities2->frequency & freq_table[i].cap)
+ freq2 = freq_table[i].rate;
+ if (freq1 && freq2)
+ break;
+ }
+ pa_assert(i >= 0);
+
+ if (freq1 > freq2)
+ return -1;
+ if (freq2 < freq1)
+ return 1;
+ }
+
+ return 0;
+}
+
+static int cmp_endpoints(const uint8_t *capabilities1_buffer, uint8_t capabilities1_size, const uint8_t *capabilities2_buffer, uint8_t capabilities2_size, const pa_sample_spec *default_sample_spec, bool for_encoding) {
+ pa_assert(capabilities1_size == sizeof(a2dp_aptx_t));
+ pa_assert(capabilities2_size == sizeof(a2dp_aptx_t));
+ return cmp_endpoints_common((const a2dp_aptx_t *)capabilities1_buffer, (const a2dp_aptx_t *)capabilities2_buffer, default_sample_spec, for_encoding);
+}
+
+static int cmp_endpoints_hd(const uint8_t *capabilities1_buffer, uint8_t capabilities1_size, const uint8_t *capabilities2_buffer, uint8_t capabilities2_size, const pa_sample_spec *default_sample_spec, bool for_encoding) {
+ pa_assert(capabilities1_size == sizeof(a2dp_aptx_hd_t));
+ pa_assert(capabilities2_size == sizeof(a2dp_aptx_hd_t));
+ return cmp_endpoints_common(&((const a2dp_aptx_hd_t *)capabilities1_buffer)->aptx, &((const a2dp_aptx_hd_t *)capabilities2_buffer)->aptx, default_sample_spec, for_encoding);
+}
+
+static void fill_capabilities_common(a2dp_aptx_t *capabilities, uint32_t vendor_id, uint16_t codec_id) {
+ capabilities->info = A2DP_SET_VENDOR_ID_CODEC_ID(vendor_id, codec_id);
+ capabilities->channel_mode = APTX_CHANNEL_MODE_STEREO;
+ capabilities->frequency = APTX_SAMPLING_FREQ_16000 | APTX_SAMPLING_FREQ_32000 |
+ APTX_SAMPLING_FREQ_44100 | APTX_SAMPLING_FREQ_48000;
+}
+
+static uint8_t fill_capabilities(uint8_t capabilities_buffer[MAX_A2DP_CAPS_SIZE]) {
+ a2dp_aptx_t *capabilities = (a2dp_aptx_t *) capabilities_buffer;
+
+ pa_zero(*capabilities);
+ fill_capabilities_common(capabilities, APTX_VENDOR_ID, APTX_CODEC_ID);
+ return sizeof(*capabilities);
+}
+
+static uint8_t fill_capabilities_hd(uint8_t capabilities_buffer[MAX_A2DP_CAPS_SIZE]) {
+ a2dp_aptx_hd_t *capabilities = (a2dp_aptx_hd_t *) capabilities_buffer;
+
+ pa_zero(*capabilities);
+ fill_capabilities_common(&capabilities->aptx, APTX_HD_VENDOR_ID, APTX_HD_CODEC_ID);
+ return sizeof(*capabilities);
+}
+
+static bool is_configuration_valid_common(const a2dp_aptx_t *config, uint32_t vendor_id, uint16_t codec_id) {
+ if (A2DP_GET_VENDOR_ID(config->info) != vendor_id || A2DP_GET_CODEC_ID(config->info) != codec_id) {
+ pa_log_error("Invalid vendor codec information in configuration");
+ return false;
+ }
+
+ if (config->frequency != APTX_SAMPLING_FREQ_16000 && config->frequency != APTX_SAMPLING_FREQ_32000 &&
+ config->frequency != APTX_SAMPLING_FREQ_44100 && config->frequency != APTX_SAMPLING_FREQ_48000) {
+ pa_log_error("Invalid sampling frequency in configuration");
+ return false;
+ }
+
+ if (config->channel_mode != APTX_CHANNEL_MODE_STEREO) {
+ pa_log_error("Invalid channel mode in configuration");
+ return false;
+ }
+
+ return true;
+}
+
+static bool is_configuration_valid(const uint8_t *config_buffer, uint8_t config_size) {
+ const a2dp_aptx_t *config = (const a2dp_aptx_t *) config_buffer;
+
+ if (config_size != sizeof(*config)) {
+ pa_log_error("Invalid size of config buffer");
+ return false;
+ }
+
+ return is_configuration_valid_common(config, APTX_VENDOR_ID, APTX_CODEC_ID);
+}
+
+static bool is_configuration_valid_hd(const uint8_t *config_buffer, uint8_t config_size) {
+ const a2dp_aptx_hd_t *config = (const a2dp_aptx_hd_t *) config_buffer;
+
+ if (config_size != sizeof(*config)) {
+ pa_log_error("Invalid size of config buffer");
+ return false;
+ }
+
+ return is_configuration_valid_common(&config->aptx, APTX_HD_VENDOR_ID, APTX_HD_CODEC_ID);
+}
+
+static bool fill_preferred_configuration_common(const pa_sample_spec *default_sample_spec, const a2dp_aptx_t *capabilities, a2dp_aptx_t *config, uint32_t vendor_id, uint16_t codec_id) {
+ int i;
+
+ static const struct {
+ uint32_t rate;
+ uint8_t cap;
+ } freq_table[] = {
+ { 16000U, APTX_SAMPLING_FREQ_16000 },
+ { 32000U, APTX_SAMPLING_FREQ_32000 },
+ { 44100U, APTX_SAMPLING_FREQ_44100 },
+ { 48000U, APTX_SAMPLING_FREQ_48000 }
+ };
+
+ if (A2DP_GET_VENDOR_ID(capabilities->info) != vendor_id || A2DP_GET_CODEC_ID(capabilities->info) != codec_id) {
+ pa_log_error("No supported vendor codec information");
+ return false;
+ }
+
+ config->info = A2DP_SET_VENDOR_ID_CODEC_ID(vendor_id, codec_id);
+
+ if (!(capabilities->channel_mode & APTX_CHANNEL_MODE_STEREO)) {
+ pa_log_error("No supported channel modes");
+ return false;
+ }
+
+ config->channel_mode = APTX_CHANNEL_MODE_STEREO;
+
+ /* Find the lowest freq that is at least as high as the requested sampling rate */
+ for (i = 0; (unsigned) i < PA_ELEMENTSOF(freq_table); i++) {
+ if (freq_table[i].rate >= default_sample_spec->rate && (capabilities->frequency & freq_table[i].cap)) {
+ config->frequency = freq_table[i].cap;
+ break;
+ }
+ }
+
+ if ((unsigned) i == PA_ELEMENTSOF(freq_table)) {
+ for (--i; i >= 0; i--) {
+ if (capabilities->frequency & freq_table[i].cap) {
+ config->frequency = freq_table[i].cap;
+ break;
+ }
+ }
+
+ if (i < 0) {
+ pa_log_error("Not suitable sample rate");
+ return false;
+ }
+ }
+
+ return true;
+}
+
+static uint8_t fill_preferred_configuration(const pa_sample_spec *default_sample_spec, const uint8_t *capabilities_buffer, uint8_t capabilities_size, uint8_t config_buffer[MAX_A2DP_CAPS_SIZE]) {
+ a2dp_aptx_t *config = (a2dp_aptx_t *) config_buffer;
+ const a2dp_aptx_t *capabilities = (const a2dp_aptx_t *) capabilities_buffer;
+
+ if (capabilities_size != sizeof(*capabilities)) {
+ pa_log_error("Invalid size of capabilities buffer");
+ return 0;
+ }
+
+ pa_zero(*config);
+
+ if (!fill_preferred_configuration_common(default_sample_spec, capabilities, config, APTX_VENDOR_ID, APTX_CODEC_ID))
+ return 0;
+
+ return sizeof(*config);
+}
+
+static uint8_t fill_preferred_configuration_hd(const pa_sample_spec *default_sample_spec, const uint8_t *capabilities_buffer, uint8_t capabilities_size, uint8_t config_buffer[MAX_A2DP_CAPS_SIZE]) {
+ a2dp_aptx_hd_t *config = (a2dp_aptx_hd_t *) config_buffer;
+ const a2dp_aptx_hd_t *capabilities = (const a2dp_aptx_hd_t *) capabilities_buffer;
+
+ if (capabilities_size != sizeof(*capabilities)) {
+ pa_log_error("Invalid size of capabilities buffer");
+ return 0;
+ }
+
+ pa_zero(*config);
+
+ if (!fill_preferred_configuration_common(default_sample_spec, &capabilities->aptx, &config->aptx, APTX_HD_VENDOR_ID, APTX_HD_CODEC_ID))
+ return 0;
+
+ return sizeof(*config);
+}
+
+static void *init_common(const a2dp_aptx_t *config, pa_sample_spec *sample_spec, int hd) {
+ struct aptx_context *aptx_c;
+
+ aptx_c = aptx_init(hd);
+ if (!aptx_c) {
+ pa_log_error("libopenaptx initialization failed");
+ return NULL;
+ }
+
+ sample_spec->format = PA_SAMPLE_S24LE;
+
+ switch (config->frequency) {
+ case APTX_SAMPLING_FREQ_16000:
+ sample_spec->rate = 16000U;
+ break;
+ case APTX_SAMPLING_FREQ_32000:
+ sample_spec->rate = 32000U;
+ break;
+ case APTX_SAMPLING_FREQ_44100:
+ sample_spec->rate = 44100U;
+ break;
+ case APTX_SAMPLING_FREQ_48000:
+ sample_spec->rate = 48000U;
+ break;
+ default:
+ pa_assert_not_reached();
+ }
+
+ switch (config->channel_mode) {
+ case APTX_CHANNEL_MODE_STEREO:
+ sample_spec->channels = 2;
+ break;
+ default:
+ pa_assert_not_reached();
+ }
+
+ PA_ONCE_BEGIN {
+#if OPENAPTX_MAJOR == 0 && OPENAPTX_MINOR == 0 && OPENAPTX_PATCH == 0
+ /* libopenaptx version 0.0.0 does not export version global variables */
+ pa_log_debug("Using aptX codec implementation: libopenaptx from https://github.com/pali/libopenaptx");
+#else
+ pa_log_debug("Using aptX codec implementation: libopenaptx %d.%d.%d from https://github.com/pali/libopenaptx", aptx_major, aptx_minor, aptx_patch);
+#endif
+ } PA_ONCE_END;
+
+ return aptx_c;
+}
+
+static void *init(bool for_encoding, bool for_backchannel, const uint8_t *config_buffer, uint8_t config_size, pa_sample_spec *sample_spec) {
+ const a2dp_aptx_t *config = (const a2dp_aptx_t *) config_buffer;
+
+ pa_assert(config_size == sizeof(*config));
+ pa_assert(!for_backchannel);
+
+ return init_common(config, sample_spec, 0);
+}
+
+static void *init_hd(bool for_encoding, bool for_backchannel, const uint8_t *config_buffer, uint8_t config_size, pa_sample_spec *sample_spec) {
+ struct aptx_hd_info *aptx_hd_info;
+ const a2dp_aptx_hd_t *config = (const a2dp_aptx_hd_t *) config_buffer;
+
+ pa_assert(config_size == sizeof(*config));
+ pa_assert(!for_backchannel);
+
+ aptx_hd_info = pa_xnew0(struct aptx_hd_info, 1);
+
+ aptx_hd_info->aptx_c = init_common(&config->aptx, sample_spec, 1);
+ if (!aptx_hd_info->aptx_c) {
+ pa_xfree(aptx_hd_info);
+ return NULL;
+ }
+
+ return aptx_hd_info;
+}
+
+static void deinit(void *codec_info) {
+ struct aptx_context *aptx_c = (struct aptx_context *) codec_info;
+
+ aptx_finish(aptx_c);
+}
+
+static void deinit_hd(void *codec_info) {
+ struct aptx_hd_info *aptx_hd_info = (struct aptx_hd_info *) codec_info;
+
+ deinit(aptx_hd_info->aptx_c);
+ pa_xfree(aptx_hd_info);
+}
+
+static int reset(void *codec_info) {
+ struct aptx_context *aptx_c = (struct aptx_context *) codec_info;
+
+ aptx_reset(aptx_c);
+ return 0;
+}
+
+static int reset_hd(void *codec_info) {
+ struct aptx_hd_info *aptx_hd_info = (struct aptx_hd_info *) codec_info;
+
+ reset(aptx_hd_info->aptx_c);
+ aptx_hd_info->seq_num = 0;
+ return 0;
+}
+
+static size_t get_block_size(void *codec_info, size_t link_mtu) {
+ /* aptX compression ratio is 6:1 and we need to process one aptX frame (4 bytes) at once */
+ size_t frame_count = (link_mtu / 4);
+
+ return frame_count * 4 * 6;
+}
+
+static size_t get_block_size_hd(void *codec_info, size_t link_mtu) {
+ /* aptX HD compression ratio is 4:1 and we need to process one aptX HD frame (6 bytes) at once, plus aptX HD frames are encapsulated in RTP */
+ size_t rtp_size = sizeof(struct rtp_header);
+ size_t frame_count = (link_mtu - rtp_size) / 6;
+
+ return frame_count * 6 * 4;
+}
+
+static size_t reduce_encoder_bitrate(void *codec_info, size_t write_link_mtu) {
+ return 0;
+}
+
+static size_t encode_buffer(void *codec_info, uint32_t timestamp, const uint8_t *input_buffer, size_t input_size, uint8_t *output_buffer, size_t output_size, size_t *processed) {
+ struct aptx_context *aptx_c = (struct aptx_context *) codec_info;
+ size_t written;
+
+ *processed = aptx_encode(aptx_c, input_buffer, input_size, output_buffer, output_size, &written);
+ if (PA_UNLIKELY(*processed == 0 || *processed != input_size))
+ pa_log_error("aptX encoding error");
+
+ return written;
+}
+
+static size_t encode_buffer_hd(void *codec_info, uint32_t timestamp, const uint8_t *input_buffer, size_t input_size, uint8_t *output_buffer, size_t output_size, size_t *processed) {
+ struct aptx_hd_info *aptx_hd_info = (struct aptx_hd_info *) codec_info;
+ struct rtp_header *header;
+ size_t written;
+
+ if (PA_UNLIKELY(output_size < sizeof(*header))) {
+ *processed = 0;
+ return 0;
+ }
+
+ written = encode_buffer(aptx_hd_info->aptx_c, timestamp, input_buffer, input_size, output_buffer + sizeof(*header), output_size - sizeof(*header), processed);
+
+ if (PA_LIKELY(written > 0)) {
+ header = (struct rtp_header *) output_buffer;
+ pa_zero(*header);
+ header->v = 2;
+ header->pt = 96;
+ header->sequence_number = htons(aptx_hd_info->seq_num++);
+ header->timestamp = htonl(timestamp);
+ header->ssrc = htonl(1);
+ written += sizeof(*header);
+ }
+
+ return written;
+}
+
+static size_t decode_buffer(void *codec_info, const uint8_t *input_buffer, size_t input_size, uint8_t *output_buffer, size_t output_size, size_t *processed) {
+ struct aptx_context *aptx_c = (struct aptx_context *) codec_info;
+ size_t written;
+
+ *processed = aptx_decode(aptx_c, input_buffer, input_size, output_buffer, output_size, &written);
+
+ /* Due to aptX latency, aptx_decode starts filling output buffer after 90 input samples.
+ * If input buffer contains less than 90 samples, aptx_decode returns zero (=no output)
+ * but set *processed to non zero as input samples were processed. So do not check for
+ * return value of aptx_decode, zero is valid. Decoding error is indicating by fact that
+ * not all input samples were processed. */
+ if (PA_UNLIKELY(*processed != input_size))
+ pa_log_error("aptX decoding error");
+
+ return written;
+}
+
+static size_t decode_buffer_hd(void *codec_info, const uint8_t *input_buffer, size_t input_size, uint8_t *output_buffer, size_t output_size, size_t *processed) {
+ struct aptx_hd_info *aptx_hd_info = (struct aptx_hd_info *) codec_info;
+ struct rtp_header *header;
+ size_t written;
+
+ if (PA_UNLIKELY(input_size < sizeof(*header))) {
+ *processed = 0;
+ return 0;
+ }
+
+ header = (struct rtp_header *) input_buffer;
+ written = decode_buffer(aptx_hd_info->aptx_c, input_buffer + sizeof(*header), input_size - sizeof(*header), output_buffer, output_size, processed);
+ *processed += sizeof(*header);
+ return written;
+}
+
+const pa_a2dp_codec pa_a2dp_codec_aptx = {
+ .name = "aptx",
+ .description = "aptX",
+ .id = { A2DP_CODEC_VENDOR, APTX_VENDOR_ID, APTX_CODEC_ID },
+ .support_backchannel = false,
+ .can_accept_capabilities = can_accept_capabilities,
+ .cmp_endpoints = cmp_endpoints,
+ .fill_capabilities = fill_capabilities,
+ .is_configuration_valid = is_configuration_valid,
+ .fill_preferred_configuration = fill_preferred_configuration,
+ .init = init,
+ .deinit = deinit,
+ .reset = reset,
+ .get_read_block_size = get_block_size,
+ .get_write_block_size = get_block_size,
+ .reduce_encoder_bitrate = reduce_encoder_bitrate,
+ .encode_buffer = encode_buffer,
+ .decode_buffer = decode_buffer,
+};
+
+const pa_a2dp_codec pa_a2dp_codec_aptx_hd = {
+ .name = "aptx_hd",
+ .description = "aptX HD",
+ .id = { A2DP_CODEC_VENDOR, APTX_HD_VENDOR_ID, APTX_HD_CODEC_ID },
+ .support_backchannel = false,
+ .can_accept_capabilities = can_accept_capabilities_hd,
+ .cmp_endpoints = cmp_endpoints_hd,
+ .fill_capabilities = fill_capabilities_hd,
+ .is_configuration_valid = is_configuration_valid_hd,
+ .fill_preferred_configuration = fill_preferred_configuration_hd,
+ .init = init_hd,
+ .deinit = deinit_hd,
+ .reset = reset_hd,
+ .get_read_block_size = get_block_size_hd,
+ .get_write_block_size = get_block_size_hd,
+ .reduce_encoder_bitrate = reduce_encoder_bitrate,
+ .encode_buffer = encode_buffer_hd,
+ .decode_buffer = decode_buffer_hd,
+};
diff --git a/src/modules/bluetooth/a2dp-codec-util.c b/src/modules/bluetooth/a2dp-codec-util.c
index aff6589ca..5ddb4573c 100644
--- a/src/modules/bluetooth/a2dp-codec-util.c
+++ b/src/modules/bluetooth/a2dp-codec-util.c
@@ -27,11 +27,19 @@
#include "a2dp-codec-util.h"
extern const pa_a2dp_codec pa_a2dp_codec_sbc;
+#ifdef HAVE_OPENAPTX
+extern const pa_a2dp_codec pa_a2dp_codec_aptx;
+extern const pa_a2dp_codec pa_a2dp_codec_aptx_hd;
+#endif
/* This is list of supported codecs. Their order is important.
* Codec with higher index has higher priority. */
static const pa_a2dp_codec *pa_a2dp_codecs[] = {
&pa_a2dp_codec_sbc,
+#ifdef HAVE_OPENAPTX
+ &pa_a2dp_codec_aptx,
+ &pa_a2dp_codec_aptx_hd,
+#endif
};
unsigned int pa_bluetooth_a2dp_codec_count(void) {
--
2.20.1
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