| /* |
| * (C) 2011 Collabora Ltd. |
| * Contact: Youness Alaoui <youness.alaoui@collabora.co.uk> |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Library General Public |
| * License as published by the Free Software Foundation; either |
| * version 2 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 |
| * Library General Public License for more details. |
| * |
| * You should have received a copy of the GNU Library General Public |
| * License along with this library; if not, write to the |
| * Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| * Boston, MA 02111-1307, USA. |
| */ |
| |
| /** |
| * SECTION:element-spanplc |
| * |
| * The spanplc (Packet Loss Concealment) element provides a synthetic |
| * fill-in signal, to minimise the audible effect of lost packets in |
| * VoIP applications |
| * |
| */ |
| |
| |
| #ifdef HAVE_CONFIG_H |
| #include <config.h> |
| #endif |
| |
| #include "gstspanplc.h" |
| |
| #include <gst/audio/audio.h> |
| |
| G_DEFINE_TYPE (GstSpanPlc, gst_span_plc, GST_TYPE_ELEMENT); |
| |
| GST_DEBUG_CATEGORY_STATIC (gst_span_plc_debug); |
| #define GST_CAT_DEFAULT gst_span_plc_debug |
| |
| |
| static GstStaticPadTemplate src_factory = GST_STATIC_PAD_TEMPLATE ("src", |
| GST_PAD_SRC, |
| GST_PAD_ALWAYS, |
| GST_STATIC_CAPS ("audio/x-raw, format=\"" GST_AUDIO_NE (S16) "\", " |
| "rate = " GST_AUDIO_RATE_RANGE " , channels = (int) 1") |
| ); |
| |
| static GstStaticPadTemplate sink_factory = GST_STATIC_PAD_TEMPLATE ("sink", |
| GST_PAD_SINK, |
| GST_PAD_ALWAYS, |
| GST_STATIC_CAPS ("audio/x-raw, format=\"" GST_AUDIO_NE (S16) "\", " |
| "rate = " GST_AUDIO_RATE_RANGE " , channels = (int) 1") |
| ); |
| |
| static void gst_span_plc_dispose (GObject * object); |
| |
| static GstStateChangeReturn gst_span_plc_change_state (GstElement * element, |
| GstStateChange transition); |
| static void gst_span_plc_setcaps_sink (GstSpanPlc * plc, GstCaps * caps); |
| static GstFlowReturn gst_span_plc_chain (GstPad * pad, GstObject * parent, |
| GstBuffer * buf); |
| static gboolean gst_span_plc_event_sink (GstPad * pad, GstObject * parent, |
| GstEvent * event); |
| |
| /* initialize the plugin's class */ |
| static void |
| gst_span_plc_class_init (GstSpanPlcClass * klass) |
| { |
| GObjectClass *gobject_class = (GObjectClass *) klass; |
| GstElementClass *gstelement_class = (GstElementClass *) klass; |
| |
| gst_element_class_add_pad_template (gstelement_class, |
| gst_static_pad_template_get (&src_factory)); |
| gst_element_class_add_pad_template (gstelement_class, |
| gst_static_pad_template_get (&sink_factory)); |
| |
| gst_element_class_set_metadata (gstelement_class, "SpanDSP PLC", |
| "Filter/Effect/Audio", |
| "Adds packet loss concealment to audio", |
| "Youness Alaoui <youness.alaoui@collabora.co.uk>"); |
| |
| gobject_class->dispose = gst_span_plc_dispose; |
| |
| gstelement_class->change_state = |
| GST_DEBUG_FUNCPTR (gst_span_plc_change_state); |
| |
| GST_DEBUG_CATEGORY_INIT (gst_span_plc_debug, "spanplc", |
| 0, "spanDSP's packet loss concealment"); |
| |
| } |
| |
| static void |
| gst_span_plc_init (GstSpanPlc * plc) |
| { |
| GST_DEBUG_OBJECT (plc, "init"); |
| |
| plc->srcpad = gst_pad_new_from_static_template (&src_factory, "src"); |
| plc->sinkpad = gst_pad_new_from_static_template (&sink_factory, "sink"); |
| |
| gst_pad_set_chain_function (plc->sinkpad, |
| GST_DEBUG_FUNCPTR (gst_span_plc_chain)); |
| gst_pad_set_event_function (plc->sinkpad, |
| GST_DEBUG_FUNCPTR (gst_span_plc_event_sink)); |
| |
| gst_element_add_pad (GST_ELEMENT (plc), plc->srcpad); |
| gst_element_add_pad (GST_ELEMENT (plc), plc->sinkpad); |
| |
| plc->plc_state = NULL; |
| |
| GST_DEBUG_OBJECT (plc, "init complete"); |
| } |
| |
| static void |
| gst_span_plc_dispose (GObject * object) |
| { |
| GstSpanPlc *plc = GST_SPAN_PLC (object); |
| |
| if (plc->plc_state) |
| plc_free (plc->plc_state); |
| plc->plc_state = NULL; |
| |
| G_OBJECT_CLASS (gst_span_plc_parent_class)->dispose (object); |
| } |
| |
| static void |
| gst_span_plc_flush (GstSpanPlc * plc, gboolean renew) |
| { |
| if (plc->plc_state) |
| plc_free (plc->plc_state); |
| if (renew) |
| plc->plc_state = plc_init (NULL); |
| else |
| plc->plc_state = NULL; |
| } |
| |
| static GstStateChangeReturn |
| gst_span_plc_change_state (GstElement * element, GstStateChange transition) |
| { |
| GstSpanPlc *plc = GST_SPAN_PLC (element); |
| GstStateChangeReturn ret; |
| |
| switch (transition) { |
| case GST_STATE_CHANGE_NULL_TO_READY: |
| gst_span_plc_flush (plc, TRUE); |
| break; |
| default: |
| break; |
| } |
| |
| ret = GST_ELEMENT_CLASS (gst_span_plc_parent_class)->change_state (element, |
| transition); |
| |
| switch (transition) { |
| case GST_STATE_CHANGE_READY_TO_NULL: |
| gst_span_plc_flush (plc, FALSE); |
| default: |
| break; |
| } |
| |
| return ret; |
| } |
| |
| static void |
| gst_span_plc_setcaps_sink (GstSpanPlc * plc, GstCaps * caps) |
| { |
| GstStructure *s = NULL; |
| gint sample_rate; |
| |
| s = gst_caps_get_structure (caps, 0); |
| if (!s) |
| return; |
| |
| gst_structure_get_int (s, "rate", &sample_rate); |
| if (sample_rate != plc->sample_rate) { |
| GST_DEBUG_OBJECT (plc, "setcaps: got sample rate : %d", sample_rate); |
| plc->sample_rate = sample_rate; |
| gst_span_plc_flush (plc, TRUE); |
| } |
| } |
| |
| static GstFlowReturn |
| gst_span_plc_chain (GstPad * pad, GstObject * parent, GstBuffer * buffer) |
| { |
| GstSpanPlc *plc = GST_SPAN_PLC (parent); |
| GstMapInfo map; |
| |
| if (plc->plc_state->missing_samples != 0) |
| buffer = gst_buffer_make_writable (buffer); |
| gst_buffer_map (buffer, &map, GST_MAP_READWRITE); |
| plc_rx (plc->plc_state, (int16_t *) map.data, map.size / 2); |
| gst_buffer_unmap (buffer, &map); |
| |
| return gst_pad_push (plc->srcpad, buffer); |
| } |
| |
| static void |
| gst_span_plc_send_fillin (GstSpanPlc * plc, GstClockTime timestamp, |
| GstClockTime duration) |
| { |
| guint buf_size; |
| GstBuffer *buffer = NULL; |
| GstMapInfo map; |
| |
| buf_size = ((float) duration / GST_SECOND) * plc->sample_rate; |
| buf_size *= sizeof (guint16); |
| buffer = gst_buffer_new_and_alloc (buf_size); |
| GST_DEBUG_OBJECT (plc, "Missing packet of %" GST_TIME_FORMAT |
| " == %d bytes", GST_TIME_ARGS (duration), buf_size); |
| gst_buffer_map (buffer, &map, GST_MAP_READWRITE); |
| plc_fillin (plc->plc_state, (int16_t *) map.data, map.size / 2); |
| gst_buffer_unmap (buffer, &map); |
| GST_BUFFER_PTS (buffer) = timestamp; |
| GST_BUFFER_DURATION (buffer) = duration; |
| gst_pad_push (plc->srcpad, buffer); |
| } |
| |
| static gboolean |
| gst_span_plc_event_sink (GstPad * pad, GstObject * parent, GstEvent * event) |
| { |
| GstSpanPlc *plc = GST_SPAN_PLC (parent); |
| |
| GST_DEBUG_OBJECT (plc, "received event %s", GST_EVENT_TYPE_NAME (event)); |
| |
| switch (GST_EVENT_TYPE (event)) { |
| case GST_EVENT_CAPS: |
| { |
| GstCaps *caps; |
| gst_event_parse_caps (event, &caps); |
| gst_span_plc_setcaps_sink (plc, caps); |
| break; |
| } |
| case GST_EVENT_GAP: |
| { |
| GstClockTime timestamp; |
| GstClockTime duration; |
| |
| gst_event_parse_gap (event, ×tamp, &duration); |
| gst_span_plc_send_fillin (plc, timestamp, duration); |
| gst_event_unref (event); |
| return TRUE; |
| } |
| case GST_EVENT_FLUSH_STOP: |
| gst_span_plc_flush (plc, TRUE); |
| break; |
| default: |
| break; |
| } |
| |
| return gst_pad_push_event (plc->srcpad, event); |
| } |