bluetooth: Add a generic GStreamer codec module
authorSanchayan Maity <sanchayan@asymptotic.io>
Tue, 27 Oct 2020 11:28:21 +0000 (16:58 +0530)
committerSanchayan Maity <sanchayan@asymptotic.io>
Tue, 19 Jan 2021 08:13:42 +0000 (13:43 +0530)
This adds a generic gstreamer codec module based on which other
bluetooth codecs viz. aptX, aptX-HD, LDAC and AAC can be supported.

The GStreamer codec plugins used here themselves depend on the native
codec implementation.

aptX/aptX-HD -> libopenaptx
LDAC         -> libldac
AAC          -> Fraunhofer FDK AAC

Part-of: <https://gitlab.freedesktop.org/pulseaudio/pulseaudio/-/merge_requests/440>

meson.build
meson_options.txt
src/modules/bluetooth/a2dp-codec-gst.c [new file with mode: 0644]
src/modules/bluetooth/a2dp-codec-gst.h [new file with mode: 0644]
src/modules/bluetooth/meson.build

index f67f875..4a7f675 100644 (file)
@@ -742,6 +742,13 @@ if gst_dep.found() and gstapp_dep.found() and gstrtp_dep.found()
   have_gstreamer = true
 endif
 
+bluez5_gst_dep = dependency('gstreamer-1.0', version : '>= 1.14', required : get_option('bluez5-gstreamer'))
+bluez5_gstapp_dep = dependency('gstreamer-app-1.0', required : get_option('bluez5-gstreamer'))
+have_bluez5_gstreamer = false
+if bluez5_gst_dep.found() and bluez5_gstapp_dep.found()
+  have_bluez5_gstreamer = true
+endif
+
 # These are required for the CMake file generation
 cdata.set('PA_LIBDIR', libdir)
 cdata.set('PA_INCDIR', includedir)
@@ -882,6 +889,7 @@ summary = [
   '  Enable BlueZ 5:              @0@'.format(get_option('bluez5')),
   '    Enable native headsets:    @0@'.format(get_option('bluez5-native-headset')),
   '    Enable  ofono headsets:    @0@'.format(get_option('bluez5-ofono-headset')),
+  '    Enable GStreamer based codecs: @0@'.format(have_bluez5_gstreamer),
   'Enable udev:                   @0@'.format(udev_dep.found()),
   '  Enable HAL->udev compat:     @0@'.format(get_option('hal-compat')),
   'Enable systemd:                @0@'.format(libsystemd_dep.found()),
index ccfa2f7..878cd39 100644 (file)
@@ -81,6 +81,9 @@ option('avahi',
 option('bluez5',
        type : 'boolean', value : 'true',
        description : 'Optional BlueZ 5 support')
+option('bluez5-gstreamer',
+       type : 'feature', value: 'auto',
+       description : 'Optional BlueZ 5 GStreamer support')
 option('bluez5-native-headset',
        type : 'boolean',
        description : 'Optional native headset backend support (BlueZ 5)')
diff --git a/src/modules/bluetooth/a2dp-codec-gst.c b/src/modules/bluetooth/a2dp-codec-gst.c
new file mode 100644 (file)
index 0000000..c714c1d
--- /dev/null
@@ -0,0 +1,751 @@
+/***
+  This file is part of PulseAudio.
+
+  Copyright (C) 2020 Asymptotic <sanchayan@asymptotic.io>
+
+  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 <arpa/inet.h>
+
+#include <pulsecore/log.h>
+#include <pulsecore/macro.h>
+#include <pulsecore/once.h>
+#include <pulsecore/core-util.h>
+#include <pulse/sample.h>
+
+#include "a2dp-codecs.h"
+#include "a2dp-codec-api.h"
+#include "a2dp-codec-gst.h"
+
+/* Called from the GStreamer streaming thread */
+static void enc_sink_eos(GstAppSink *appsink, gpointer userdata) {
+    pa_log_debug("Encoder got EOS");
+}
+
+/* Called from the GStreamer streaming thread */
+static GstFlowReturn enc_sink_new_sample(GstAppSink *appsink, gpointer userdata) {
+    struct gst_info *info = (struct gst_info *) userdata;
+    GstSample *sample = NULL;
+    GstBuffer *buf;
+
+    sample = gst_app_sink_pull_sample(GST_APP_SINK(info->enc_sink));
+    if (!sample)
+        return GST_FLOW_OK;
+
+    buf = gst_sample_get_buffer(sample);
+    gst_buffer_ref(buf);
+    gst_adapter_push(info->enc_adapter, buf);
+    gst_sample_unref(sample);
+    pa_fdsem_post(info->enc_fdsem);
+
+    return GST_FLOW_OK;
+}
+
+/* Called from the GStreamer streaming thread */
+static void dec_sink_eos(GstAppSink *appsink, gpointer userdata) {
+    pa_log_debug("Decoder got EOS");
+}
+
+/* Called from the GStreamer streaming thread */
+static GstFlowReturn dec_sink_new_sample(GstAppSink *appsink, gpointer userdata) {
+    struct gst_info *info = (struct gst_info *) userdata;
+    GstSample *sample = NULL;
+    GstBuffer *buf;
+
+    sample = gst_app_sink_pull_sample(GST_APP_SINK(info->dec_sink));
+    if (!sample)
+        return GST_FLOW_OK;
+
+    buf = gst_sample_get_buffer(sample);
+    gst_buffer_ref(buf);
+    gst_adapter_push(info->dec_adapter, buf);
+    gst_sample_unref(sample);
+    pa_fdsem_post(info->dec_fdsem);
+
+    return GST_FLOW_OK;
+}
+
+static void gst_deinit_enc_common(struct gst_info *info) {
+    if (!info)
+        return;
+    if (info->enc_fdsem)
+        pa_fdsem_free(info->enc_fdsem);
+    if (info->enc_src)
+        gst_object_unref(info->enc_src);
+    if (info->gst_enc)
+        gst_object_unref(info->gst_enc);
+    if (info->enc_sink)
+        gst_object_unref(info->enc_sink);
+    if (info->enc_adapter)
+        g_object_unref(info->enc_adapter);
+    if (info->enc_pipeline)
+        gst_object_unref(info->enc_pipeline);
+}
+
+static void gst_deinit_dec_common(struct gst_info *info) {
+    if (!info)
+        return;
+    if (info->dec_fdsem)
+        pa_fdsem_free(info->dec_fdsem);
+    if (info->dec_src)
+        gst_object_unref(info->dec_src);
+    if (info->gst_dec)
+        gst_object_unref(info->gst_dec);
+    if (info->dec_sink)
+        gst_object_unref(info->dec_sink);
+    if (info->dec_adapter)
+        g_object_unref(info->dec_adapter);
+    if (info->dec_pipeline)
+        gst_object_unref(info->dec_pipeline);
+}
+
+static bool gst_init_ldac(struct gst_info *info, pa_sample_spec *ss) {
+    GstElement *rtpldacpay;
+    GstElement *enc;
+    GstCaps *caps;
+
+    ss->format = PA_SAMPLE_S32LE;
+
+    switch (info->a2dp_codec_t.ldac_config->frequency) {
+        case LDAC_SAMPLING_FREQ_44100:
+            ss->rate = 44100u;
+            break;
+        case LDAC_SAMPLING_FREQ_48000:
+            ss->rate = 48000u;
+            break;
+        case LDAC_SAMPLING_FREQ_88200:
+            ss->rate = 88200;
+            break;
+        case LDAC_SAMPLING_FREQ_96000:
+            ss->rate = 96000;
+            break;
+        default:
+            pa_log_error("LDAC invalid frequency %d", info->a2dp_codec_t.ldac_config->frequency);
+            goto fail;
+    }
+
+    switch (info->a2dp_codec_t.ldac_config->channel_mode) {
+        case LDAC_CHANNEL_MODE_STEREO:
+            ss->channels = 2;
+            break;
+        case LDAC_CHANNEL_MODE_MONO:
+            ss->channels = 1;
+            break;
+        case LDAC_CHANNEL_MODE_DUAL:
+            ss->channels = 1;
+            break;
+        default:
+            pa_log_error("LDAC invalid channel mode %d", info->a2dp_codec_t.ldac_config->channel_mode);
+            goto fail;
+    }
+
+    enc = gst_element_factory_make("ldacenc", "ldac_enc");
+    if (!enc) {
+        pa_log_error("Could not create LDAC encoder element");
+        goto fail;
+    }
+
+    switch (info->codec_type) {
+        case LDAC_EQMID_HQ:
+            g_object_set(enc, "eqmid", 0, NULL);
+            break;
+        case LDAC_EQMID_SQ:
+            g_object_set(enc, "eqmid", 1, NULL);
+            break;
+        case LDAC_EQMID_MQ:
+            g_object_set(enc, "eqmid", 2, NULL);
+            break;
+        default:
+            goto fail;
+    }
+
+    caps = gst_caps_new_simple("audio/x-raw",
+            "format", G_TYPE_STRING, "S32LE",
+            "rate", G_TYPE_INT, (int) ss->rate,
+            "channels", G_TYPE_INT, (int) ss->channels,
+            "channel-mask", G_TYPE_INT, 0,
+            "layout", G_TYPE_STRING, "interleaved",
+            NULL);
+    g_object_set(info->enc_src, "caps", caps, NULL);
+    gst_caps_unref(caps);
+
+    rtpldacpay = gst_element_factory_make("rtpldacpay", "rtp_ldac_pay");
+    if (!rtpldacpay) {
+        pa_log_error("Could not create RTP LDAC payloader element");
+        goto fail;
+    }
+
+    gst_bin_add_many(GST_BIN(info->enc_pipeline), info->enc_src, enc, rtpldacpay, info->enc_sink, NULL);
+
+    if (!gst_element_link_many(info->enc_src, enc, rtpldacpay, info->enc_sink, NULL)) {
+        pa_log_error("Failed to link elements for LDAC encoder");
+        goto bin_remove;
+    }
+
+    if (gst_element_set_state(info->enc_pipeline, GST_STATE_PLAYING) == GST_STATE_CHANGE_FAILURE) {
+        pa_log_error("Could not start LDAC encoder pipeline");
+        goto bin_remove;
+    }
+
+    info->gst_enc = enc;
+
+    return true;
+
+bin_remove:
+    gst_bin_remove_many(GST_BIN(info->enc_pipeline), info->enc_src, enc, rtpldacpay, info->enc_sink, NULL);
+fail:
+    pa_log_error("LDAC encoder initialisation failed");
+    return false;
+}
+
+static bool gst_init_aptx(struct gst_info *info, pa_sample_spec *ss) {
+    GstElement *enc, *dec;
+    GstCaps *caps;
+    const char *aptx_codec_media_type;
+
+    ss->format = PA_SAMPLE_S24LE;
+
+    if (info->codec_type == APTX_HD) {
+        switch (info->a2dp_codec_t.aptx_hd_config->aptx.frequency) {
+            case APTX_SAMPLING_FREQ_16000:
+                ss->rate = 16000u;
+                break;
+            case APTX_SAMPLING_FREQ_32000:
+                ss->rate = 32000u;
+                break;
+            case APTX_SAMPLING_FREQ_44100:
+                ss->rate = 44100u;
+                break;
+            case APTX_SAMPLING_FREQ_48000:
+                ss->rate = 48000u;
+                break;
+            default:
+                pa_log_error("aptX HD invalid frequency %d", info->a2dp_codec_t.aptx_hd_config->aptx.frequency);
+                goto fail;
+        }
+
+        switch (info->a2dp_codec_t.aptx_hd_config->aptx.channel_mode) {
+            case APTX_CHANNEL_MODE_STEREO:
+                ss->channels = 2;
+                break;
+            default:
+                pa_log_error("aptX HD invalid channel mode %d", info->a2dp_codec_t.aptx_hd_config->aptx.frequency);
+                goto fail;
+        }
+    } else {
+        switch (info->a2dp_codec_t.aptx_config->frequency) {
+            case APTX_SAMPLING_FREQ_16000:
+                ss->rate = 16000u;
+                break;
+            case APTX_SAMPLING_FREQ_32000:
+                ss->rate = 32000u;
+                break;
+            case APTX_SAMPLING_FREQ_44100:
+                ss->rate = 44100u;
+                break;
+            case APTX_SAMPLING_FREQ_48000:
+                ss->rate = 48000u;
+                break;
+            default:
+                pa_log_error("aptX invalid frequency %d", info->a2dp_codec_t.aptx_config->frequency);
+                goto fail;
+        }
+
+        switch (info->a2dp_codec_t.aptx_config->channel_mode) {
+            case APTX_CHANNEL_MODE_STEREO:
+                ss->channels = 2;
+                break;
+            default:
+                pa_log_error("aptX invalid channel mode %d", info->a2dp_codec_t.aptx_config->frequency);
+                goto fail;
+        }
+    }
+
+    enc = gst_element_factory_make("openaptxenc", "aptx_encoder");
+
+    if (enc == NULL) {
+        pa_log_error("Could not create aptX encoder element");
+        goto fail;
+    }
+
+    dec = gst_element_factory_make("openaptxdec", "aptx_decoder");
+
+    if (dec == NULL) {
+        pa_log_error("Could not create aptX decoder element");
+        goto fail;
+    }
+
+    aptx_codec_media_type = info->codec_type == APTX_HD ? "audio/aptx-hd" : "audio/aptx";
+
+    caps = gst_caps_new_simple("audio/x-raw",
+            "format", G_TYPE_STRING, "S24LE",
+            "rate", G_TYPE_INT, (int) ss->rate,
+            "channels", G_TYPE_INT, (int) ss->channels,
+            "channel-mask", G_TYPE_INT, 0,
+            "layout", G_TYPE_STRING, "interleaved",
+            NULL);
+    g_object_set(info->enc_src, "caps", caps, NULL);
+    gst_caps_unref(caps);
+
+    caps = gst_caps_new_simple(aptx_codec_media_type,
+            "rate", G_TYPE_INT, (int) ss->rate,
+            "channels", G_TYPE_INT, (int) ss->channels,
+            NULL);
+    g_object_set(info->enc_sink, "caps", caps, NULL);
+    gst_caps_unref(caps);
+
+    caps = gst_caps_new_simple(aptx_codec_media_type,
+            "rate", G_TYPE_INT, (int) ss->rate,
+            "channels", G_TYPE_INT, (int) ss->channels,
+            NULL);
+    g_object_set(info->dec_src, "caps", caps, NULL);
+    gst_caps_unref(caps);
+
+    caps = gst_caps_new_simple("audio/x-raw",
+            "format", G_TYPE_STRING, "S24LE",
+            "rate", G_TYPE_INT, (int) ss->rate,
+            "channels", G_TYPE_INT, (int) ss->channels,
+            "layout", G_TYPE_STRING, "interleaved",
+            NULL);
+    g_object_set(info->dec_sink, "caps", caps, NULL);
+    gst_caps_unref(caps);
+
+    gst_bin_add_many(GST_BIN(info->enc_pipeline), info->enc_src, enc, info->enc_sink, NULL);
+    gst_bin_add_many(GST_BIN(info->dec_pipeline), info->dec_src, dec, info->dec_sink, NULL);
+
+    if (!gst_element_link_many(info->enc_src, enc, info->enc_sink, NULL)) {
+        pa_log_error("Failed to link elements for aptX encoder");
+        goto bin_remove;
+    }
+
+    if (!gst_element_link_many(info->dec_src, dec, info->dec_sink, NULL)) {
+        pa_log_error("Failed to link elements for aptX decoder");
+        goto bin_remove;
+    }
+
+    if (gst_element_set_state(info->enc_pipeline, GST_STATE_PLAYING) == GST_STATE_CHANGE_FAILURE) {
+        pa_log_error("Could not start aptX encoder pipeline");
+        goto bin_remove;
+    }
+
+    if (gst_element_set_state(info->dec_pipeline, GST_STATE_PLAYING) == GST_STATE_CHANGE_FAILURE) {
+        pa_log_error("Could not start aptX decoder pipeline");
+        goto bin_remove;
+    }
+
+    info->gst_enc = enc;
+    info->gst_dec = dec;
+
+    return true;
+
+bin_remove:
+    gst_bin_remove_many(GST_BIN(info->enc_pipeline), info->enc_src, enc, info->enc_sink, NULL);
+    gst_bin_remove_many(GST_BIN(info->dec_pipeline), info->dec_src, dec, info->dec_sink, NULL);
+fail:
+    pa_log_error("aptX initialisation failed");
+    return false;
+}
+
+static bool gst_init_enc_common(struct gst_info *info, pa_sample_spec *ss) {
+    GstElement *pipeline = NULL;
+    GstElement *appsrc = NULL, *appsink = NULL;
+    GstAdapter *adapter;
+    GstAppSinkCallbacks callbacks = { 0, };
+
+    appsrc = gst_element_factory_make("appsrc", "enc_source");
+    if (!appsrc) {
+        pa_log_error("Could not create appsrc element");
+        goto fail;
+    }
+    g_object_set(appsrc, "is-live", FALSE, "format", GST_FORMAT_TIME, "stream-type", 0, "max-bytes", 0, NULL);
+
+    appsink = gst_element_factory_make("appsink", "enc_sink");
+    if (!appsink) {
+        pa_log_error("Could not create appsink element");
+        goto fail;
+    }
+    g_object_set(appsink, "sync", FALSE, "async", FALSE, "enable-last-sample", FALSE, NULL);
+
+    callbacks.eos = enc_sink_eos;
+    callbacks.new_sample = enc_sink_new_sample;
+    gst_app_sink_set_callbacks(GST_APP_SINK(appsink), &callbacks, info, NULL);
+
+    adapter = gst_adapter_new();
+    pa_assert(adapter);
+
+    pipeline = gst_pipeline_new(NULL);
+    pa_assert(pipeline);
+
+    info->enc_src = appsrc;
+    info->enc_sink = appsink;
+    info->enc_adapter = adapter;
+    info->enc_pipeline = pipeline;
+    info->enc_fdsem = pa_fdsem_new();
+
+    return true;
+
+fail:
+    gst_deinit_enc_common(info);
+
+    return false;
+}
+
+static bool gst_init_dec_common(struct gst_info *info, pa_sample_spec *ss) {
+    GstElement *pipeline = NULL;
+    GstElement *appsrc = NULL, *appsink = NULL;
+    GstAdapter *adapter;
+    GstAppSinkCallbacks callbacks = { 0, };
+
+    appsrc = gst_element_factory_make("appsrc", "dec_source");
+    if (!appsrc) {
+        pa_log_error("Could not create decoder appsrc element");
+        goto fail;
+    }
+    g_object_set(appsrc, "is-live", FALSE, "format", GST_FORMAT_TIME, "stream-type", 0, "max-bytes", 0, NULL);
+
+    appsink = gst_element_factory_make("appsink", "dec_sink");
+    if (!appsink) {
+        pa_log_error("Could not create decoder appsink element");
+        goto fail;
+    }
+    g_object_set(appsink, "sync", FALSE, "async", FALSE, "enable-last-sample", FALSE, NULL);
+
+    callbacks.eos = dec_sink_eos;
+    callbacks.new_sample = dec_sink_new_sample;
+    gst_app_sink_set_callbacks(GST_APP_SINK(appsink), &callbacks, info, NULL);
+
+    adapter = gst_adapter_new();
+    pa_assert(adapter);
+
+    pipeline = gst_pipeline_new(NULL);
+    pa_assert(pipeline);
+
+    info->dec_src = appsrc;
+    info->dec_sink = appsink;
+    info->dec_adapter = adapter;
+    info->dec_pipeline = pipeline;
+    info->dec_fdsem = pa_fdsem_new();
+
+    return true;
+
+fail:
+    gst_deinit_dec_common(info);
+
+    return false;
+}
+
+/*
+ * The idea of using buffer probes is as follows. We set a buffer probe on the
+ * encoder sink pad. In the buffer probe, we set an idle probe on the upstream
+ * source pad. In encode_buffer, we wait on the fdsem. The fdsem gets posted
+ * when either new_sample or idle probe gets called. We do this, to make the
+ * appsink behave synchronously.
+ *
+ * For buffer probes, see
+ * https://gstreamer.freedesktop.org/documentation/additional/design/probes.html?gi-language=c
+ */
+static GstPadProbeReturn gst_enc_appsink_buffer_probe(GstPad *pad, GstPadProbeInfo *probe_info, gpointer userdata)
+{
+    struct gst_info *info = (struct gst_info *)userdata;
+
+    pa_assert(probe_info->type & GST_PAD_PROBE_TYPE_IDLE);
+
+    pa_fdsem_post(info->enc_fdsem);
+
+    return GST_PAD_PROBE_REMOVE;
+}
+
+static GstPadProbeReturn gst_encoder_buffer_probe(GstPad *pad, GstPadProbeInfo *probe_info, gpointer userdata)
+{
+    struct gst_info *info = (struct gst_info *)userdata;
+    GstPad *peer_pad;
+
+    pa_assert(probe_info->type & GST_PAD_PROBE_TYPE_BUFFER);
+
+    peer_pad = gst_pad_get_peer(pad);
+    gst_pad_add_probe(peer_pad, GST_PAD_PROBE_TYPE_IDLE, gst_enc_appsink_buffer_probe, info, NULL);
+    gst_object_unref(peer_pad);
+
+    return GST_PAD_PROBE_OK;
+}
+
+static GstPadProbeReturn gst_dec_appsink_buffer_probe(GstPad *pad, GstPadProbeInfo *probe_info, gpointer userdata)
+{
+    struct gst_info *info = (struct gst_info *)userdata;
+
+    pa_assert(probe_info->type & GST_PAD_PROBE_TYPE_IDLE);
+
+    pa_fdsem_post(info->dec_fdsem);
+
+    return GST_PAD_PROBE_REMOVE;
+}
+
+static GstPadProbeReturn gst_decoder_buffer_probe(GstPad *pad, GstPadProbeInfo *probe_info, gpointer userdata)
+{
+    struct gst_info *info = (struct gst_info *)userdata;
+    GstPad *peer_pad;
+
+    pa_assert(probe_info->type & GST_PAD_PROBE_TYPE_BUFFER);
+
+    peer_pad = gst_pad_get_peer(pad);
+    gst_pad_add_probe(peer_pad, GST_PAD_PROBE_TYPE_IDLE, gst_dec_appsink_buffer_probe, info, NULL);
+    gst_object_unref(peer_pad);
+
+    return GST_PAD_PROBE_OK;
+}
+
+static bool gst_init_common(struct gst_info *info, pa_sample_spec *ss) {
+    GstPad *pad;
+
+    info->seq_num = 0;
+
+    if (!gst_init_enc_common(info, ss))
+        goto fail;
+
+    switch (info->codec_type) {
+        case AAC:
+            goto fail;
+            break;
+        case APTX:
+        case APTX_HD:
+            if (!gst_init_dec_common(info, ss))
+                goto enc_fail;
+
+            if (!gst_init_aptx(info, ss))
+                goto dec_fail;
+            break;
+        case LDAC_EQMID_HQ:
+        case LDAC_EQMID_SQ:
+        case LDAC_EQMID_MQ:
+            if (!gst_init_ldac(info, ss))
+                goto dec_fail;
+            break;
+        default:
+            goto fail;
+    }
+
+    /* See the comment on buffer probe functions */
+    if (info->gst_enc) {
+        pad = gst_element_get_static_pad(info->gst_enc, "sink");
+        gst_pad_add_probe(pad, GST_PAD_PROBE_TYPE_BUFFER, gst_encoder_buffer_probe, info, NULL);
+        gst_object_unref(pad);
+    }
+
+    if (info->gst_dec) {
+        pad = gst_element_get_static_pad(info->gst_dec, "sink");
+        gst_pad_add_probe(pad, GST_PAD_PROBE_TYPE_BUFFER, gst_decoder_buffer_probe, info, NULL);
+        gst_object_unref(pad);
+    }
+
+    pa_log_info("Gstreamer pipeline initialisation succeeded");
+
+    return true;
+
+dec_fail:
+    if (info->dec_pipeline) {
+        gst_element_set_state(info->dec_pipeline, GST_STATE_NULL);
+        gst_object_unref(info->dec_pipeline);
+    }
+enc_fail:
+    if (info->enc_pipeline) {
+        gst_element_set_state(info->enc_pipeline, GST_STATE_NULL);
+        gst_object_unref(info->enc_pipeline);
+    }
+fail:
+    pa_log_error("Gstreamer pipeline initialisation failed");
+
+    return false;
+}
+
+void *gst_codec_init(enum a2dp_codec_type codec_type, const uint8_t *config_buffer, uint8_t config_size, pa_sample_spec *ss) {
+    struct gst_info *info = NULL;
+    GError *error = NULL;
+    bool ret;
+
+    if (!gst_init_check(NULL, NULL, &error)) {
+        pa_log_error("Could not initialise GStreamer: %s", error->message);
+        g_error_free(error);
+        goto fail;
+    }
+
+    info = pa_xnew0(struct gst_info, 1);
+    pa_assert(info);
+
+    switch (codec_type) {
+        case AAC:
+            info->codec_type = AAC;
+            info->a2dp_codec_t.aac_config = (const a2dp_aac_t *) config_buffer;
+            pa_assert(config_size == sizeof(*(info->a2dp_codec_t.aac_config)));
+            break;
+        case APTX:
+            info->codec_type = APTX;
+            info->a2dp_codec_t.aptx_config = (const a2dp_aptx_t *) config_buffer;
+            pa_assert(config_size == sizeof(*(info->a2dp_codec_t.aptx_config)));
+            break;
+        case APTX_HD:
+            info->codec_type = APTX_HD;
+            info->a2dp_codec_t.aptx_hd_config = (const a2dp_aptx_hd_t *) config_buffer;
+            pa_assert(config_size == sizeof(*(info->a2dp_codec_t.aptx_hd_config)));
+            break;
+        case LDAC_EQMID_HQ:
+        case LDAC_EQMID_SQ:
+        case LDAC_EQMID_MQ:
+            info->codec_type = codec_type;
+            info->a2dp_codec_t.ldac_config = (const a2dp_ldac_t *) config_buffer;
+            pa_assert(config_size == sizeof(*(info->a2dp_codec_t.ldac_config)));
+            break;
+        default:
+            pa_log_error("Unsupported bluetooth codec");
+            goto fail;
+    }
+
+    ret = gst_init_common(info, ss);
+    if (!ret)
+        goto fail;
+
+    info->ss = ss;
+
+    pa_log_info("Rate: %d Channels: %d Format: %d", ss->rate, ss->channels, ss->format);
+
+    return info;
+
+fail:
+    if (info)
+        pa_xfree(info);
+
+    return NULL;
+}
+
+size_t gst_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 gst_info *info = (struct gst_info *) codec_info;
+    gsize available, encoded;
+    GstBuffer *in_buf;
+    GstMapInfo map_info;
+    GstFlowReturn ret;
+    size_t written = 0;
+
+    in_buf = gst_buffer_new_allocate(NULL, input_size, NULL);
+    pa_assert(in_buf);
+
+    pa_assert_se(gst_buffer_map(in_buf, &map_info, GST_MAP_WRITE));
+    memcpy(map_info.data, input_buffer, input_size);
+    gst_buffer_unmap(in_buf, &map_info);
+
+    ret = gst_app_src_push_buffer(GST_APP_SRC(info->enc_src), in_buf);
+    if (ret != GST_FLOW_OK) {
+        pa_log_error("failed to push buffer for encoding %d", ret);
+        goto fail;
+    }
+
+    pa_fdsem_wait(info->enc_fdsem);
+
+    available = gst_adapter_available(info->enc_adapter);
+
+    if (available) {
+        encoded = PA_MIN(available, output_size);
+
+        gst_adapter_copy(info->enc_adapter, output_buffer, 0, encoded);
+        gst_adapter_flush(info->enc_adapter, encoded);
+
+        written += encoded;
+    } else
+        pa_log_debug("No encoded data available in adapter");
+
+    *processed = input_size;
+
+    return written;
+
+fail:
+    *processed = 0;
+
+    return written;
+}
+
+size_t gst_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 gst_info *info = (struct gst_info *) codec_info;
+    gsize available, decoded;
+    GstBuffer *in_buf;
+    GstMapInfo map_info;
+    GstFlowReturn ret;
+    size_t written = 0;
+
+    in_buf = gst_buffer_new_allocate(NULL, input_size, NULL);
+    pa_assert(in_buf);
+
+    pa_assert_se(gst_buffer_map(in_buf, &map_info, GST_MAP_WRITE));
+    memcpy(map_info.data, input_buffer, input_size);
+    gst_buffer_unmap(in_buf, &map_info);
+
+    ret = gst_app_src_push_buffer(GST_APP_SRC(info->dec_src), in_buf);
+    if (ret != GST_FLOW_OK) {
+        pa_log_error("failed to push buffer for decoding %d", ret);
+        goto fail;
+    }
+
+    pa_fdsem_wait(info->dec_fdsem);
+
+    available = gst_adapter_available(info->dec_adapter);
+
+    if (available) {
+        decoded = PA_MIN(available, output_size);
+
+        gst_adapter_copy(info->dec_adapter, output_buffer, 0, decoded);
+        gst_adapter_flush(info->dec_adapter, decoded);
+
+        written += decoded;
+    } else
+        pa_log_debug("No decoded data available in adapter");
+
+    *processed = input_size;
+
+    return written;
+
+fail:
+    *processed = 0;
+
+    return written;
+}
+
+void gst_codec_deinit(void *codec_info) {
+    struct gst_info *info = (struct gst_info *) codec_info;
+
+    if (info->enc_fdsem)
+        pa_fdsem_free(info->enc_fdsem);
+
+    if (info->dec_fdsem)
+        pa_fdsem_free(info->dec_fdsem);
+
+    if (info->enc_pipeline) {
+        gst_element_set_state(info->enc_pipeline, GST_STATE_NULL);
+        gst_object_unref(info->enc_pipeline);
+    }
+
+    if (info->dec_pipeline) {
+        gst_element_set_state(info->dec_pipeline, GST_STATE_NULL);
+        gst_object_unref(info->dec_pipeline);
+    }
+
+    if (info->enc_adapter)
+        g_object_unref(info->enc_adapter);
+
+    if (info->dec_adapter)
+        g_object_unref(info->dec_adapter);
+
+    pa_xfree(info);
+}
diff --git a/src/modules/bluetooth/a2dp-codec-gst.h b/src/modules/bluetooth/a2dp-codec-gst.h
new file mode 100644 (file)
index 0000000..4cf0e68
--- /dev/null
@@ -0,0 +1,60 @@
+/***
+  This file is part of PulseAudio.
+
+  Copyright (C) 2020 Asymptotic <sanchayan@asymptotic.io>
+
+  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/>.
+***/
+
+#include <gst/gst.h>
+#include <gst/app/gstappsrc.h>
+#include <gst/app/gstappsink.h>
+#include <gst/base/gstadapter.h>
+#include <pulsecore/fdsem.h>
+
+enum a2dp_codec_type {
+    AAC = 0,
+    APTX,
+    APTX_HD,
+    LDAC_EQMID_HQ,
+    LDAC_EQMID_SQ,
+    LDAC_EQMID_MQ
+};
+
+struct gst_info {
+    pa_sample_spec *ss;
+    enum a2dp_codec_type codec_type;
+    union {
+        const a2dp_aac_t *aac_config;
+        const a2dp_aptx_t *aptx_config;
+        const a2dp_aptx_hd_t *aptx_hd_config;
+        const a2dp_ldac_t *ldac_config;
+    } a2dp_codec_t;
+
+    GstElement *gst_enc, *gst_dec;
+    GstElement *enc_src, *enc_sink;
+    GstElement *dec_src, *dec_sink;
+    GstElement *enc_pipeline, *dec_pipeline;
+    GstAdapter *enc_adapter, *dec_adapter;
+
+    pa_fdsem *enc_fdsem;
+    pa_fdsem *dec_fdsem;
+
+    uint16_t seq_num;
+};
+
+void *gst_codec_init(enum a2dp_codec_type codec_type, const uint8_t *config_buffer, uint8_t config_size, pa_sample_spec *ss);
+size_t gst_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);
+size_t gst_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);
+void gst_codec_deinit(void *codec_info);
index 9982cba..f820d4b 100644 (file)
@@ -20,13 +20,18 @@ if get_option('bluez5-ofono-headset')
   libbluez5_util_sources += [ 'backend-ofono.c' ]
 endif
 
+if have_bluez5_gstreamer
+  libbluez5_util_headers += [ 'a2dp-codec-gst.h' ]
+  libbluez5_util_sources += [ 'a2dp-codec-gst.c' ]
+endif
+
 libbluez5_util = shared_library('bluez5-util',
   libbluez5_util_sources,
   libbluez5_util_headers,
   c_args : [pa_c_args, server_c_args],
   link_args : [nodelete_link_args],
   include_directories : [configinc, topinc],
-  dependencies : [libpulse_dep, libpulsecommon_dep, libpulsecore_dep, dbus_dep, sbc_dep, libintl_dep],
+  dependencies : [libpulse_dep, libpulsecommon_dep, libpulsecore_dep, dbus_dep, sbc_dep, libintl_dep, bluez5_gst_dep, bluez5_gstapp_dep],
   install : true,
   install_rpath : privlibdir,
   install_dir : modlibexecdir,