--- /dev/null
+/* GStreamer LDAC audio encoder
+ * Copyright (C) 2020 Asymptotic <sanchayan@asymptotic.io>
+ *
+ * This library 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.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ */
+
+/**
+ * SECTION:element-ldacenc
+ * @title: ldacenc
+ *
+ * This element encodes raw integer PCM audio into a Bluetooth LDAC audio.
+ *
+ * ## Example pipeline
+ * |[
+ * gst-launch-1.0 -v audiotestsrc ! ldacenc ! rtpldacpay mtu=679 ! avdtpsink
+ * ]| Encode a sine wave into LDAC, RTP payload it and send over bluetooth
+ *
+ * Since: 1.20
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <string.h>
+
+#include "gstldacenc.h"
+
+/*
+ * MTU size required for LDAC A2DP streaming. Required for initializing the
+ * encoder.
+ */
+#define GST_LDAC_MTU_REQUIRED 679
+
+GST_DEBUG_CATEGORY_STATIC (ldac_enc_debug);
+#define GST_CAT_DEFAULT ldac_enc_debug
+
+#define parent_class gst_ldac_enc_parent_class
+G_DEFINE_TYPE (GstLdacEnc, gst_ldac_enc, GST_TYPE_AUDIO_ENCODER);
+
+static GstStaticPadTemplate ldac_enc_sink_factory =
+GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS,
+ GST_STATIC_CAPS
+ ("audio/x-raw, format=(string) { S16LE, S24LE, S32LE, F32LE }, "
+ "rate = (int) { 44100, 48000, 88200, 96000 }, "
+ "channels = (int) [ 1, 2 ] "));
+
+static GstStaticPadTemplate ldac_enc_src_factory =
+ GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
+ GST_STATIC_CAPS ("audio/x-ldac, "
+ "rate = (int) { 44100, 48000, 88200, 96000 }, "
+ "channels = (int) 1, channel-mode = (string)mono; "
+ "audio/x-ldac, "
+ "rate = (int) { 44100, 48000, 882000, 96000 }, "
+ "channels = (int) 2, " "channel-mode = (string) { dual, stereo }"));
+
+enum
+{
+ PROP_0,
+ PROP_EQMID
+};
+
+static void gst_ldac_enc_get_property (GObject * object,
+ guint property_id, GValue * value, GParamSpec * pspec);
+static void gst_ldac_enc_set_property (GObject * object,
+ guint property_id, const GValue * value, GParamSpec * pspec);
+
+static gboolean gst_ldac_enc_start (GstAudioEncoder * enc);
+static gboolean gst_ldac_enc_stop (GstAudioEncoder * enc);
+static gboolean gst_ldac_enc_set_format (GstAudioEncoder * enc,
+ GstAudioInfo * info);
+static gboolean gst_ldac_enc_negotiate (GstAudioEncoder * enc);
+static GstFlowReturn gst_ldac_enc_handle_frame (GstAudioEncoder * enc,
+ GstBuffer * buffer);
+static guint gst_ldac_enc_get_num_frames (guint eqmid, guint channels);
+static guint gst_ldac_enc_get_frame_length (guint eqmid, guint channels);
+static guint gst_ldac_enc_get_num_samples (guint rate);
+
+#define GST_LDAC_EQMID (gst_ldac_eqmid_get_type ())
+static GType
+gst_ldac_eqmid_get_type (void)
+{
+ static GType ldac_eqmid_type = 0;
+ static const GEnumValue eqmid_types[] = {
+ {GST_LDAC_EQMID_HQ, "HQ", "hq"},
+ {GST_LDAC_EQMID_SQ, "SQ", "sq"},
+ {GST_LDAC_EQMID_MQ, "MQ", "mq"},
+ {0, NULL, NULL}
+ };
+
+ if (!ldac_eqmid_type)
+ ldac_eqmid_type = g_enum_register_static ("GstLdacEqmid", eqmid_types);
+
+ return ldac_eqmid_type;
+}
+
+static void
+gst_ldac_enc_class_init (GstLdacEncClass * klass)
+{
+ GstAudioEncoderClass *encoder_class = GST_AUDIO_ENCODER_CLASS (klass);
+ GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
+ GObjectClass *gobject_class = (GObjectClass *) klass;
+
+ gobject_class->set_property = gst_ldac_enc_set_property;
+ gobject_class->get_property = gst_ldac_enc_get_property;
+
+ encoder_class->start = GST_DEBUG_FUNCPTR (gst_ldac_enc_start);
+ encoder_class->stop = GST_DEBUG_FUNCPTR (gst_ldac_enc_stop);
+ encoder_class->set_format = GST_DEBUG_FUNCPTR (gst_ldac_enc_set_format);
+ encoder_class->handle_frame = GST_DEBUG_FUNCPTR (gst_ldac_enc_handle_frame);
+ encoder_class->negotiate = GST_DEBUG_FUNCPTR (gst_ldac_enc_negotiate);
+
+ g_object_class_install_property (gobject_class, PROP_EQMID,
+ g_param_spec_enum ("eqmid", "Encode Quality Mode Index",
+ "Encode Quality Mode Index. 0: High Quality 1: Standard Quality "
+ "2: Mobile Use Quality", GST_LDAC_EQMID,
+ GST_LDAC_EQMID_SQ, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+ gst_element_class_add_static_pad_template (element_class,
+ &ldac_enc_sink_factory);
+ gst_element_class_add_static_pad_template (element_class,
+ &ldac_enc_src_factory);
+
+ gst_element_class_set_static_metadata (element_class,
+ "Bluetooth LDAC audio encoder", "Codec/Encoder/Audio",
+ "Encode an LDAC audio stream",
+ "Sanchayan Maity <sanchayan@asymptotic.io>");
+
+ GST_DEBUG_CATEGORY_INIT (ldac_enc_debug, "ldacenc", 0,
+ "LDAC encoding element");
+}
+
+static void
+gst_ldac_enc_init (GstLdacEnc * self)
+{
+ GST_PAD_SET_ACCEPT_TEMPLATE (GST_AUDIO_ENCODER_SINK_PAD (self));
+ self->eqmid = GST_LDAC_EQMID_SQ;
+ self->channel_mode = 0;
+ self->init_done = FALSE;
+}
+
+static void
+gst_ldac_enc_set_property (GObject * object, guint property_id,
+ const GValue * value, GParamSpec * pspec)
+{
+ GstLdacEnc *self = GST_LDAC_ENC (object);
+
+ switch (property_id) {
+ case PROP_EQMID:
+ self->eqmid = g_value_get_enum (value);
+ break;
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+ break;
+ }
+}
+
+static void
+gst_ldac_enc_get_property (GObject * object, guint property_id,
+ GValue * value, GParamSpec * pspec)
+{
+ GstLdacEnc *self = GST_LDAC_ENC (object);
+
+ switch (property_id) {
+ case PROP_EQMID:
+ g_value_set_enum (value, self->eqmid);
+ break;
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+ break;
+ }
+}
+
+static GstCaps *
+gst_ldac_enc_do_negotiate (GstAudioEncoder * audio_enc)
+{
+ GstLdacEnc *enc = GST_LDAC_ENC (audio_enc);
+ GstCaps *caps, *filter_caps;
+ GstCaps *output_caps = NULL;
+ GstStructure *s;
+
+ /* Negotiate output format based on downstream caps restrictions */
+ caps = gst_pad_get_allowed_caps (GST_AUDIO_ENCODER_SRC_PAD (enc));
+ if (caps == GST_CAPS_NONE || gst_caps_is_empty (caps))
+ goto failure;
+
+ if (caps == NULL)
+ caps = gst_static_pad_template_get_caps (&ldac_enc_src_factory);
+
+ /* Fixate output caps */
+ filter_caps = gst_caps_new_simple ("audio/x-ldac", "rate", G_TYPE_INT,
+ enc->rate, "channels", G_TYPE_INT, enc->channels, NULL);
+ output_caps = gst_caps_intersect (caps, filter_caps);
+ gst_caps_unref (filter_caps);
+
+ if (output_caps == NULL || gst_caps_is_empty (output_caps)) {
+ GST_WARNING_OBJECT (enc, "Couldn't negotiate output caps with input rate "
+ "%d and input channels %d and allowed output caps %" GST_PTR_FORMAT,
+ enc->rate, enc->channels, caps);
+ goto failure;
+ }
+
+ gst_clear_caps (&caps);
+
+ GST_DEBUG_OBJECT (enc, "fixating caps %" GST_PTR_FORMAT, output_caps);
+ output_caps = gst_caps_truncate (output_caps);
+ s = gst_caps_get_structure (output_caps, 0);
+ if (enc->channels == 1)
+ gst_structure_fixate_field_string (s, "channel-mode", "mono");
+ else
+ gst_structure_fixate_field_string (s, "channel-mode", "stereo");
+ s = NULL;
+
+ /* In case there's anything else left to fixate */
+ output_caps = gst_caps_fixate (output_caps);
+ gst_caps_set_simple (output_caps, "framed", G_TYPE_BOOLEAN, TRUE, NULL);
+
+ GST_INFO_OBJECT (enc, "output caps %" GST_PTR_FORMAT, output_caps);
+
+ if (enc->channels == 1)
+ enc->channel_mode = LDACBT_CHANNEL_MODE_MONO;
+ else
+ enc->channel_mode = LDACBT_CHANNEL_MODE_STEREO;
+
+ return output_caps;
+
+failure:
+ if (output_caps)
+ gst_caps_unref (output_caps);
+ if (caps)
+ gst_caps_unref (caps);
+ return NULL;
+}
+
+static gboolean
+gst_ldac_enc_negotiate (GstAudioEncoder * audio_enc)
+{
+ GstLdacEnc *enc = GST_LDAC_ENC (audio_enc);
+ GstCaps *output_caps = NULL;
+
+ output_caps = gst_ldac_enc_do_negotiate (audio_enc);
+ if (output_caps == NULL) {
+ GST_ERROR_OBJECT (enc, "failed to negotiate");
+ return FALSE;
+ }
+
+ if (!gst_audio_encoder_set_output_format (audio_enc, output_caps)) {
+ GST_ERROR_OBJECT (enc, "failed to configure output caps on src pad");
+ gst_caps_unref (output_caps);
+ return FALSE;
+ }
+ gst_caps_unref (output_caps);
+
+ return GST_AUDIO_ENCODER_CLASS (parent_class)->negotiate (audio_enc);
+}
+
+static gboolean
+gst_ldac_enc_set_format (GstAudioEncoder * audio_enc, GstAudioInfo * info)
+{
+ GstLdacEnc *enc = GST_LDAC_ENC (audio_enc);
+ GstCaps *output_caps = NULL;
+ guint num_ldac_frames, num_samples;
+ gint ret = 0;
+
+ enc->rate = GST_AUDIO_INFO_RATE (info);
+ enc->channels = GST_AUDIO_INFO_CHANNELS (info);
+
+ switch (GST_AUDIO_INFO_FORMAT (info)) {
+ case GST_AUDIO_FORMAT_S16:
+ enc->ldac_fmt = LDACBT_SMPL_FMT_S16;
+ break;
+ case GST_AUDIO_FORMAT_S24:
+ enc->ldac_fmt = LDACBT_SMPL_FMT_S24;
+ break;
+ case GST_AUDIO_FORMAT_S32:
+ enc->ldac_fmt = LDACBT_SMPL_FMT_S32;
+ break;
+ case GST_AUDIO_FORMAT_F32:
+ enc->ldac_fmt = LDACBT_SMPL_FMT_F32;
+ break;
+ default:
+ GST_ERROR_OBJECT (enc, "Invalid audio format");
+ return FALSE;
+ }
+
+ output_caps = gst_ldac_enc_do_negotiate (audio_enc);
+ if (output_caps == NULL) {
+ GST_ERROR_OBJECT (enc, "failed to negotiate");
+ return FALSE;
+ }
+
+ if (!gst_audio_encoder_set_output_format (audio_enc, output_caps)) {
+ GST_ERROR_OBJECT (enc, "failed to configure output caps on src pad");
+ gst_caps_unref (output_caps);
+ return FALSE;
+ }
+ gst_caps_unref (output_caps);
+
+ num_samples = gst_ldac_enc_get_num_samples (enc->rate);
+ num_ldac_frames = gst_ldac_enc_get_num_frames (enc->eqmid, enc->channels);
+ gst_audio_encoder_set_frame_samples_min (audio_enc,
+ num_samples * num_ldac_frames);
+
+ /*
+ * If initialisation was already done means caps have changed, close the
+ * handle. Closed handle can be initialised and used again.
+ */
+ if (enc->init_done) {
+ ldacBT_close_handle (enc->ldac);
+ enc->init_done = FALSE;
+ }
+
+ /*
+ * libldac exposes a bluetooth centric API and emits multiple LDAC frames
+ * depending on the MTU. The MTU is required for LDAC A2DP streaming, is
+ * inclusive of the RTP header and is required by the encoder. The internal
+ * encoder API is not exposed in the public interface.
+ */
+ ret =
+ ldacBT_init_handle_encode (enc->ldac, GST_LDAC_MTU_REQUIRED, enc->eqmid,
+ enc->channel_mode, enc->ldac_fmt, enc->rate);
+ if (ret != 0) {
+ GST_ERROR_OBJECT (enc, "Failed to initialize LDAC handle, ret: %d", ret);
+ return FALSE;
+ }
+ enc->init_done = TRUE;
+
+ return TRUE;
+}
+
+static GstFlowReturn
+gst_ldac_enc_handle_frame (GstAudioEncoder * audio_enc, GstBuffer * buffer)
+{
+ GstLdacEnc *enc = GST_LDAC_ENC (audio_enc);
+ GstMapInfo in_map, out_map;
+ GstAudioInfo *info;
+ GstBuffer *outbuf;
+ const guint8 *in_data;
+ guint8 *out_data;
+ gint encoded, to_encode = 0;
+ gint samples_consumed = 0;
+ guint frames, frame_len;
+ guint ldac_enc_read = 0;
+ guint frame_count = 0;
+
+ if (buffer == NULL)
+ return GST_FLOW_OK;
+
+ if (!gst_buffer_map (buffer, &in_map, GST_MAP_READ)) {
+ GST_ELEMENT_ERROR (audio_enc, STREAM, FAILED, (NULL),
+ ("Failed to map data from input buffer"));
+ return GST_FLOW_ERROR;
+ }
+
+ info = gst_audio_encoder_get_audio_info (audio_enc);
+ ldac_enc_read = LDACBT_ENC_LSU * info->bpf;
+ /*
+ * We may produce extra frames at the end of encoding process (See below).
+ * Consider some additional frames while allocating output buffer if this
+ * happens.
+ */
+ frames = (in_map.size / ldac_enc_read) + 4;
+
+ frame_len = gst_ldac_enc_get_frame_length (enc->eqmid, info->channels);
+ outbuf = gst_audio_encoder_allocate_output_buffer (audio_enc,
+ frames * frame_len);
+ if (outbuf == NULL)
+ goto no_buffer;
+
+ gst_buffer_map (outbuf, &out_map, GST_MAP_WRITE);
+ in_data = in_map.data;
+ out_data = out_map.data;
+ to_encode = in_map.size;
+
+ /*
+ * ldacBT_encode does not generate an output frame each time it is called.
+ * For each invocation, it consumes number of sample * bpf bytes of data.
+ * Depending on the eqmid setting and channels, it will emit multiple frames
+ * only after the required number of frames are packed for payloading. Below
+ * for loop exists primarily to handle this.
+ */
+ for (;;) {
+ guint8 pcm[LDACBT_MAX_LSU * 4 /* bytes/sample */ * 2 /* ch */ ] = { 0 };
+ gint ldac_frame_num, written;
+ guint8 *inp_data = NULL;
+ gboolean done = FALSE;
+ gint ret;
+
+ /*
+ * Even with minimum frame samples specified in set_format with EOS,
+ * we may get a buffer which is not a multiple of LDACBT_ENC_LSU. LDAC
+ * encoder always reads a multiple of this and to handle this scenario
+ * we use local PCM array and in the last iteration when buffer bytes
+ * < LDACBT_ENC_LSU * bpf, we copy only to_encode bytes to prevent
+ * walking off the end of input buffer and the rest of the bytes in
+ * PCM buffer would be zero, so should be safe from encoding point of
+ * view.
+ */
+ if (to_encode < 0) {
+ /*
+ * We got < LDACBT_ENC_LSU * bpf for last iteration. Force the encoder
+ * to encode the remaining bytes in buffer by passing NULL to the input
+ * PCM buffer argument.
+ */
+ inp_data = NULL;
+ done = TRUE;
+ } else if (to_encode >= ldac_enc_read) {
+ memcpy (pcm, in_data, ldac_enc_read);
+ inp_data = &pcm[0];
+ } else if (to_encode > 0 && to_encode < ldac_enc_read) {
+ memcpy (pcm, in_data, to_encode);
+ inp_data = &pcm[0];
+ }
+
+ /*
+ * Note that while we do not explicitly pass length of data to library
+ * anywhere, based on the initialization considering eqmid and rate, the
+ * library will consume a fix number of samples per call. This combined
+ * with the previous step ensures that the library does not read outside
+ * of in_data and out_data.
+ */
+ ret = ldacBT_encode (enc->ldac, (void *) inp_data, &encoded,
+ (guint8 *) out_data, &written, &ldac_frame_num);
+ if (ret < 0) {
+ GST_ERROR_OBJECT (enc, "encoding error, ret = %d written = %d",
+ ret, ldac_frame_num);
+ goto encoding_error;
+ } else {
+ to_encode -= encoded;
+ in_data = in_data + encoded;
+ out_data = out_data + written;
+ frame_count += ldac_frame_num;
+
+ GST_LOG_OBJECT (enc,
+ "To Encode: %d, Encoded: %d, Written: %d, LDAC Frames: %d", to_encode,
+ encoded, written, ldac_frame_num);
+
+ if (done || (to_encode == 0 && encoded == ldac_enc_read))
+ break;
+ }
+ }
+
+ gst_buffer_unmap (outbuf, &out_map);
+
+ if (frame_count > 0) {
+ samples_consumed = in_map.size / info->bpf;
+ gst_buffer_set_size (outbuf, frame_count * frame_len);
+ } else {
+ samples_consumed = 0;
+ gst_buffer_replace (&outbuf, NULL);
+ }
+
+ gst_buffer_unmap (buffer, &in_map);
+
+ return gst_audio_encoder_finish_frame (audio_enc, outbuf, samples_consumed);
+
+no_buffer:
+ {
+ gst_buffer_unmap (buffer, &in_map);
+
+ GST_ERROR_OBJECT (enc, "could not allocate output buffer");
+
+ return GST_FLOW_ERROR;
+ }
+encoding_error:
+ {
+ gst_buffer_unmap (buffer, &in_map);
+
+ ldacBT_free_handle (enc->ldac);
+
+ enc->ldac = NULL;
+
+ return GST_FLOW_ERROR;
+ }
+}
+
+static gboolean
+gst_ldac_enc_start (GstAudioEncoder * audio_enc)
+{
+ GstLdacEnc *enc = GST_LDAC_ENC (audio_enc);
+
+ GST_INFO_OBJECT (enc, "Setup LDAC codec");
+ /* Note that this only allocates the LDAC handle */
+ enc->ldac = ldacBT_get_handle ();
+ if (enc->ldac == NULL) {
+ GST_ERROR_OBJECT (enc, "Failed to get LDAC handle");
+ return FALSE;
+ }
+
+ return TRUE;
+}
+
+static gboolean
+gst_ldac_enc_stop (GstAudioEncoder * audio_enc)
+{
+ GstLdacEnc *enc = GST_LDAC_ENC (audio_enc);
+
+ GST_INFO_OBJECT (enc, "Finish LDAC codec");
+
+ if (enc->ldac) {
+ ldacBT_free_handle (enc->ldac);
+ enc->ldac = NULL;
+ }
+
+ enc->eqmid = GST_LDAC_EQMID_SQ;
+ enc->channel_mode = 0;
+ enc->init_done = FALSE;
+
+ return TRUE;
+}
+
+/**
+ * gst_ldac_enc_get_frame_length
+ * @eqmid: Encode Quality Mode Index
+ * @channels: Number of channels
+ *
+ * Returns: Frame length.
+ */
+static guint
+gst_ldac_enc_get_frame_length (guint eqmid, guint channels)
+{
+ g_assert (channels == 1 || channels == 2);
+
+ switch (eqmid) {
+ /* Encode setting for High Quality */
+ case GST_LDAC_EQMID_HQ:
+ return 165 * channels;
+ /* Encode setting for Standard Quality */
+ case GST_LDAC_EQMID_SQ:
+ return 110 * channels;
+ /* Encode setting for Mobile use Quality */
+ case GST_LDAC_EQMID_MQ:
+ return 55 * channels;
+ default:
+ break;
+ }
+
+ g_assert_not_reached ();
+
+ /* If assertion gets compiled out */
+ return 110 * channels;
+}
+
+/**
+ * gst_ldac_enc_get_num_frames
+ * @eqmid: Encode Quality Mode Index
+ * @channels: Number of channels
+ *
+ * Returns: Number of LDAC frames per packet.
+ */
+static guint
+gst_ldac_enc_get_num_frames (guint eqmid, guint channels)
+{
+ g_assert (channels == 1 || channels == 2);
+
+ switch (eqmid) {
+ /* Encode setting for High Quality */
+ case GST_LDAC_EQMID_HQ:
+ return 4 / channels;
+ /* Encode setting for Standard Quality */
+ case GST_LDAC_EQMID_SQ:
+ return 6 / channels;
+ /* Encode setting for Mobile use Quality */
+ case GST_LDAC_EQMID_MQ:
+ return 12 / channels;
+ default:
+ break;
+ }
+
+ g_assert_not_reached ();
+
+ /* If assertion gets compiled out */
+ return 6 / channels;
+}
+
+/**
+ * gst_ldac_enc_get_num_samples
+ * @rate: Sampling rate
+ *
+ * Number of samples in input PCM signal for encoding is fixed to
+ * LDACBT_ENC_LSU viz. 128 samples/channel and it is not affected
+ * by sampling frequency. However, frame size is 128 samples at 44.1
+ * and 48 KHz and 256 at 88.2 and 96 KHz.
+ *
+ * Returns: Number of samples / channel
+ */
+static guint
+gst_ldac_enc_get_num_samples (guint rate)
+{
+ switch (rate) {
+ case 44100:
+ case 48000:
+ return 128;
+ case 88200:
+ case 96000:
+ return 256;
+ default:
+ break;
+ }
+
+ g_assert_not_reached ();
+
+ /* If assertion gets compiled out */
+ return 128;
+}
projects / platform / upstream / gstreamer.git / commitdiff