/* GStreamer * Copyright (C) 1999,2000 Erik Walthinsen * 2001 Thomas * 2005,2006 Wim Taymans * * adder.c: Adder element, N in, one out, samples are added * * 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-adder * * The adder allows to mix several streams into one by adding the data. * Mixed data is clamped to the min/max values of the data format. * * The adder currently mixes all data received on the sinkpads as soon as * possible without trying to synchronize the streams. * * * Example launch line * |[ * gst-launch audiotestsrc freq=100 ! adder name=mix ! audioconvert ! alsasink audiotestsrc freq=500 ! mix. * ]| This pipeline produces two sine waves mixed together. * * * Last reviewed on 2006-05-09 (0.10.7) */ /* Element-Checklist-Version: 5 */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include "gstadder.h" #include #include /* strcmp */ /* highest positive/lowest negative x-bit value we can use for clamping */ #define MAX_INT_32 ((gint32) (0x7fffffff)) #define MAX_INT_16 ((gint16) (0x7fff)) #define MAX_INT_8 ((gint8) (0x7f)) #define MAX_UINT_32 ((guint32)(0xffffffff)) #define MAX_UINT_16 ((guint16)(0xffff)) #define MAX_UINT_8 ((guint8) (0xff)) #define MIN_INT_32 ((gint32) (0x80000000)) #define MIN_INT_16 ((gint16) (0x8000)) #define MIN_INT_8 ((gint8) (0x80)) #define MIN_UINT_32 ((guint32)(0x00000000)) #define MIN_UINT_16 ((guint16)(0x0000)) #define MIN_UINT_8 ((guint8) (0x00)) #define GST_CAT_DEFAULT gst_adder_debug GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT); /* elementfactory information */ #define CAPS \ "audio/x-raw-int, " \ "rate = (int) [ 1, MAX ], " \ "channels = (int) [ 1, MAX ], " \ "endianness = (int) BYTE_ORDER, " \ "width = (int) 32, " \ "depth = (int) 32, " \ "signed = (boolean) { true, false } ;" \ "audio/x-raw-int, " \ "rate = (int) [ 1, MAX ], " \ "channels = (int) [ 1, MAX ], " \ "endianness = (int) BYTE_ORDER, " \ "width = (int) 16, " \ "depth = (int) 16, " \ "signed = (boolean) { true, false } ;" \ "audio/x-raw-int, " \ "rate = (int) [ 1, MAX ], " \ "channels = (int) [ 1, MAX ], " \ "endianness = (int) BYTE_ORDER, " \ "width = (int) 8, " \ "depth = (int) 8, " \ "signed = (boolean) { true, false } ;" \ "audio/x-raw-float, " \ "rate = (int) [ 1, MAX ], " \ "channels = (int) [ 1, MAX ], " \ "endianness = (int) BYTE_ORDER, " \ "width = (int) { 32, 64 }" static GstStaticPadTemplate gst_adder_src_template = GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS, GST_STATIC_CAPS (CAPS) ); static GstStaticPadTemplate gst_adder_sink_template = GST_STATIC_PAD_TEMPLATE ("sink%d", GST_PAD_SINK, GST_PAD_REQUEST, GST_STATIC_CAPS (CAPS) ); static void gst_adder_class_init (GstAdderClass * klass); static void gst_adder_init (GstAdder * adder); static void gst_adder_finalize (GObject * object); static gboolean gst_adder_setcaps (GstPad * pad, GstCaps * caps); static gboolean gst_adder_query (GstPad * pad, GstQuery * query); static gboolean gst_adder_src_event (GstPad * pad, GstEvent * event); static gboolean gst_adder_sink_event (GstPad * pad, GstEvent * event); static GstPad *gst_adder_request_new_pad (GstElement * element, GstPadTemplate * temp, const gchar * unused); static void gst_adder_release_pad (GstElement * element, GstPad * pad); static GstStateChangeReturn gst_adder_change_state (GstElement * element, GstStateChange transition); static GstFlowReturn gst_adder_collected (GstCollectPads * pads, gpointer user_data); static GstElementClass *parent_class = NULL; GType gst_adder_get_type (void) { static GType adder_type = 0; if (G_UNLIKELY (adder_type == 0)) { static const GTypeInfo adder_info = { sizeof (GstAdderClass), NULL, NULL, (GClassInitFunc) gst_adder_class_init, NULL, NULL, sizeof (GstAdder), 0, (GInstanceInitFunc) gst_adder_init, }; adder_type = g_type_register_static (GST_TYPE_ELEMENT, "GstAdder", &adder_info, 0); GST_DEBUG_CATEGORY_INIT (GST_CAT_DEFAULT, "adder", 0, "audio channel mixing element"); } return adder_type; } /* clipping versions */ #define MAKE_FUNC(name,type,ttype,min,max) \ static void name (type *out, type *in, gint bytes) { \ gint i; \ for (i = 0; i < bytes / sizeof (type); i++) \ out[i] = CLAMP ((ttype)out[i] + (ttype)in[i], min, max); \ } /* non-clipping versions (for float) */ #define MAKE_FUNC_NC(name,type,ttype) \ static void name (type *out, type *in, gint bytes) { \ gint i; \ for (i = 0; i < bytes / sizeof (type); i++) \ out[i] = (ttype)out[i] + (ttype)in[i]; \ } /* *INDENT-OFF* */ MAKE_FUNC (add_int32, gint32, gint64, MIN_INT_32, MAX_INT_32) MAKE_FUNC (add_int16, gint16, gint32, MIN_INT_16, MAX_INT_16) MAKE_FUNC (add_int8, gint8, gint16, MIN_INT_8, MAX_INT_8) MAKE_FUNC (add_uint32, guint32, guint64, MIN_UINT_32, MAX_UINT_32) MAKE_FUNC (add_uint16, guint16, guint32, MIN_UINT_16, MAX_UINT_16) MAKE_FUNC (add_uint8, guint8, guint16, MIN_UINT_8, MAX_UINT_8) MAKE_FUNC_NC (add_float64, gdouble, gdouble) MAKE_FUNC_NC (add_float32, gfloat, gfloat) /* *INDENT-ON* */ /* we can only accept caps that we and downstream can handle. */ static GstCaps * gst_adder_sink_getcaps (GstPad * pad) { GstAdder *adder; GstCaps *result, *peercaps, *sinkcaps; adder = GST_ADDER (GST_PAD_PARENT (pad)); GST_OBJECT_LOCK (adder); /* get the downstream possible caps */ peercaps = gst_pad_peer_get_caps (adder->srcpad); /* get the allowed caps on this sinkpad, we use the fixed caps function so * that it does not call recursively in this function. */ sinkcaps = gst_pad_get_fixed_caps_func (pad); if (peercaps) { /* if the peer has caps, intersect */ GST_DEBUG_OBJECT (adder, "intersecting peer and template caps"); result = gst_caps_intersect (peercaps, sinkcaps); gst_caps_unref (peercaps); gst_caps_unref (sinkcaps); } else { /* the peer has no caps (or there is no peer), just use the allowed caps * of this sinkpad. */ GST_DEBUG_OBJECT (adder, "no peer caps, using sinkcaps"); result = sinkcaps; } GST_OBJECT_UNLOCK (adder); return result; } /* the first caps we receive on any of the sinkpads will define the caps for all * the other sinkpads because we can only mix streams with the same caps. * */ static gboolean gst_adder_setcaps (GstPad * pad, GstCaps * caps) { GstAdder *adder; GList *pads; GstStructure *structure; const char *media_type; adder = GST_ADDER (GST_PAD_PARENT (pad)); GST_LOG_OBJECT (adder, "setting caps on pad %p,%s to %" GST_PTR_FORMAT, pad, GST_PAD_NAME (pad), caps); /* FIXME, see if the other pads can accept the format. Also lock the * format on the other pads to this new format. */ GST_OBJECT_LOCK (adder); pads = GST_ELEMENT (adder)->pads; while (pads) { GstPad *otherpad = GST_PAD (pads->data); if (otherpad != pad) { gst_caps_replace (&GST_PAD_CAPS (otherpad), caps); } pads = g_list_next (pads); } GST_OBJECT_UNLOCK (adder); /* parse caps now */ structure = gst_caps_get_structure (caps, 0); media_type = gst_structure_get_name (structure); if (strcmp (media_type, "audio/x-raw-int") == 0) { GST_DEBUG_OBJECT (adder, "parse_caps sets adder to format int"); adder->format = GST_ADDER_FORMAT_INT; gst_structure_get_int (structure, "width", &adder->width); gst_structure_get_int (structure, "depth", &adder->depth); gst_structure_get_int (structure, "endianness", &adder->endianness); gst_structure_get_boolean (structure, "signed", &adder->is_signed); if (adder->endianness != G_BYTE_ORDER) goto not_supported; switch (adder->width) { case 8: adder->func = (adder->is_signed ? (GstAdderFunction) add_int8 : (GstAdderFunction) add_uint8); break; case 16: adder->func = (adder->is_signed ? (GstAdderFunction) add_int16 : (GstAdderFunction) add_uint16); break; case 32: adder->func = (adder->is_signed ? (GstAdderFunction) add_int32 : (GstAdderFunction) add_uint32); break; default: goto not_supported; } } else if (strcmp (media_type, "audio/x-raw-float") == 0) { GST_DEBUG_OBJECT (adder, "parse_caps sets adder to format float"); adder->format = GST_ADDER_FORMAT_FLOAT; gst_structure_get_int (structure, "width", &adder->width); gst_structure_get_int (structure, "endianness", &adder->endianness); if (adder->endianness != G_BYTE_ORDER) goto not_supported; switch (adder->width) { case 32: adder->func = (GstAdderFunction) add_float32; break; case 64: adder->func = (GstAdderFunction) add_float64; break; default: goto not_supported; } } else { goto not_supported; } gst_structure_get_int (structure, "channels", &adder->channels); gst_structure_get_int (structure, "rate", &adder->rate); /* precalc bps */ adder->bps = (adder->width / 8) * adder->channels; return TRUE; /* ERRORS */ not_supported: { GST_DEBUG_OBJECT (adder, "unsupported format set as caps"); return FALSE; } } /* FIXME, the duration query should reflect how long you will produce * data, that is the amount of stream time until you will emit EOS. * * For synchronized mixing this is always the max of all the durations * of upstream since we emit EOS when all of them finished. * * We don't do synchronized mixing so this really depends on where the * streams where punched in and what their relative offsets are against * eachother which we can get from the first timestamps we see. * * When we add a new stream (or remove a stream) the duration might * also become invalid again and we need to post a new DURATION * message to notify this fact to the parent. * For now we take the max of all the upstream elements so the simple * cases work at least somewhat. */ static gboolean gst_adder_query_duration (GstAdder * adder, GstQuery * query) { gint64 max; gboolean res; GstFormat format; GstIterator *it; gboolean done; /* parse format */ gst_query_parse_duration (query, &format, NULL); max = -1; res = TRUE; done = FALSE; it = gst_element_iterate_sink_pads (GST_ELEMENT_CAST (adder)); while (!done) { GstIteratorResult ires; gpointer item; ires = gst_iterator_next (it, &item); switch (ires) { case GST_ITERATOR_DONE: done = TRUE; break; case GST_ITERATOR_OK: { GstPad *pad = GST_PAD_CAST (item); gint64 duration; /* ask sink peer for duration */ res &= gst_pad_query_peer_duration (pad, &format, &duration); /* take max from all valid return values */ if (res) { /* valid unknown length, stop searching */ if (duration == -1) { max = duration; done = TRUE; } /* else see if bigger than current max */ else if (duration > max) max = duration; } gst_object_unref (pad); break; } case GST_ITERATOR_RESYNC: max = -1; res = TRUE; gst_iterator_resync (it); break; default: res = FALSE; done = TRUE; break; } } gst_iterator_free (it); if (res) { /* and store the max */ GST_DEBUG_OBJECT (adder, "Total duration in format %s: %" GST_TIME_FORMAT, gst_format_get_name (format), GST_TIME_ARGS (max)); gst_query_set_duration (query, format, max); } return res; } static gboolean gst_adder_query_latency (GstAdder * adder, GstQuery * query) { GstClockTime min, max; gboolean live; gboolean res; GstIterator *it; gboolean done; res = TRUE; done = FALSE; live = FALSE; min = 0; max = GST_CLOCK_TIME_NONE; /* Take maximum of all latency values */ it = gst_element_iterate_sink_pads (GST_ELEMENT_CAST (adder)); while (!done) { GstIteratorResult ires; gpointer item; ires = gst_iterator_next (it, &item); switch (ires) { case GST_ITERATOR_DONE: done = TRUE; break; case GST_ITERATOR_OK: { GstPad *pad = GST_PAD_CAST (item); GstQuery *peerquery; GstClockTime min_cur, max_cur; gboolean live_cur; peerquery = gst_query_new_latency (); /* Ask peer for latency */ res &= gst_pad_peer_query (pad, peerquery); /* take max from all valid return values */ if (res) { gst_query_parse_latency (peerquery, &live_cur, &min_cur, &max_cur); if (min_cur > min) min = min_cur; if (max_cur != GST_CLOCK_TIME_NONE && ((max != GST_CLOCK_TIME_NONE && max_cur > max) || (max == GST_CLOCK_TIME_NONE))) max = max_cur; live = live || live_cur; } gst_query_unref (peerquery); gst_object_unref (pad); break; } case GST_ITERATOR_RESYNC: live = FALSE; min = 0; max = GST_CLOCK_TIME_NONE; res = TRUE; gst_iterator_resync (it); break; default: res = FALSE; done = TRUE; break; } } gst_iterator_free (it); if (res) { /* store the results */ GST_DEBUG_OBJECT (adder, "Calculated total latency: live %s, min %" GST_TIME_FORMAT ", max %" GST_TIME_FORMAT, (live ? "yes" : "no"), GST_TIME_ARGS (min), GST_TIME_ARGS (max)); gst_query_set_latency (query, live, min, max); } return res; } static gboolean gst_adder_query (GstPad * pad, GstQuery * query) { GstAdder *adder = GST_ADDER (gst_pad_get_parent (pad)); gboolean res = FALSE; switch (GST_QUERY_TYPE (query)) { case GST_QUERY_POSITION: { GstFormat format; gst_query_parse_position (query, &format, NULL); switch (format) { case GST_FORMAT_TIME: /* FIXME, bring to stream time, might be tricky */ gst_query_set_position (query, format, adder->timestamp); res = TRUE; break; case GST_FORMAT_DEFAULT: gst_query_set_position (query, format, adder->offset); res = TRUE; break; default: break; } break; } case GST_QUERY_DURATION: res = gst_adder_query_duration (adder, query); break; case GST_QUERY_LATENCY: res = gst_adder_query_latency (adder, query); break; default: /* FIXME, needs a custom query handler because we have multiple * sinkpads */ res = gst_pad_query_default (pad, query); break; } gst_object_unref (adder); return res; } static gboolean forward_event_func (GstPad * pad, GValue * ret, GstEvent * event) { gst_event_ref (event); GST_LOG_OBJECT (pad, "About to send event %s", GST_EVENT_TYPE_NAME (event)); if (!gst_pad_push_event (pad, event)) { g_value_set_boolean (ret, FALSE); GST_WARNING_OBJECT (pad, "Sending event %p (%s) failed.", event, GST_EVENT_TYPE_NAME (event)); } else { GST_LOG_OBJECT (pad, "Sent event %p (%s).", event, GST_EVENT_TYPE_NAME (event)); } gst_object_unref (pad); return TRUE; } /* forwards the event to all sinkpads, takes ownership of the * event * * Returns: TRUE if the event could be forwarded on all * sinkpads. */ static gboolean forward_event (GstAdder * adder, GstEvent * event) { gboolean ret; GstIterator *it; GValue vret = { 0 }; GST_LOG_OBJECT (adder, "Forwarding event %p (%s)", event, GST_EVENT_TYPE_NAME (event)); ret = TRUE; g_value_init (&vret, G_TYPE_BOOLEAN); g_value_set_boolean (&vret, TRUE); it = gst_element_iterate_sink_pads (GST_ELEMENT_CAST (adder)); gst_iterator_fold (it, (GstIteratorFoldFunction) forward_event_func, &vret, event); gst_iterator_free (it); gst_event_unref (event); ret = g_value_get_boolean (&vret); return ret; } static gboolean gst_adder_src_event (GstPad * pad, GstEvent * event) { GstAdder *adder; gboolean result; adder = GST_ADDER (gst_pad_get_parent (pad)); switch (GST_EVENT_TYPE (event)) { case GST_EVENT_QOS: /* QoS might be tricky */ result = FALSE; break; case GST_EVENT_SEEK: { GstSeekFlags flags; GstSeekType curtype; gint64 cur; /* parse the seek parameters */ gst_event_parse_seek (event, &adder->segment_rate, NULL, &flags, &curtype, &cur, NULL, NULL); /* check if we are flushing */ if (flags & GST_SEEK_FLAG_FLUSH) { /* make sure we accept nothing anymore and return WRONG_STATE */ gst_collect_pads_set_flushing (adder->collect, TRUE); /* flushing seek, start flush downstream, the flush will be done * when all pads received a FLUSH_STOP. */ gst_pad_push_event (adder->srcpad, gst_event_new_flush_start ()); } /* now wait for the collected to be finished and mark a new * segment */ GST_OBJECT_LOCK (adder->collect); if (curtype == GST_SEEK_TYPE_SET) adder->segment_position = cur; else adder->segment_position = 0; adder->segment_pending = TRUE; GST_OBJECT_UNLOCK (adder->collect); result = forward_event (adder, event); break; } case GST_EVENT_NAVIGATION: /* navigation is rather pointless. */ result = FALSE; break; default: /* just forward the rest for now */ result = forward_event (adder, event); break; } gst_object_unref (adder); return result; } static gboolean gst_adder_sink_event (GstPad * pad, GstEvent * event) { GstAdder *adder; gboolean ret; adder = GST_ADDER (gst_pad_get_parent (pad)); GST_DEBUG ("Got %s event on pad %s:%s", GST_EVENT_TYPE_NAME (event), GST_DEBUG_PAD_NAME (pad)); switch (GST_EVENT_TYPE (event)) { case GST_EVENT_FLUSH_STOP: /* mark a pending new segment. This event is synchronized * with the streaming thread so we can safely update the * variable without races. It's somewhat weird because we * assume the collectpads forwarded the FLUSH_STOP past us * and downstream (using our source pad, the bastard!). */ adder->segment_pending = TRUE; break; default: break; } /* now GstCollectPads can take care of the rest, e.g. EOS */ ret = adder->collect_event (pad, event); gst_object_unref (adder); return ret; } static void gst_adder_class_init (GstAdderClass * klass) { GObjectClass *gobject_class; GstElementClass *gstelement_class; gobject_class = (GObjectClass *) klass; gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_adder_finalize); gstelement_class = (GstElementClass *) klass; gst_element_class_add_pad_template (gstelement_class, gst_static_pad_template_get (&gst_adder_src_template)); gst_element_class_add_pad_template (gstelement_class, gst_static_pad_template_get (&gst_adder_sink_template)); gst_element_class_set_details_simple (gstelement_class, "Adder", "Generic/Audio", "Add N audio channels together", "Thomas "); parent_class = g_type_class_peek_parent (klass); gstelement_class->request_new_pad = GST_DEBUG_FUNCPTR (gst_adder_request_new_pad); gstelement_class->release_pad = GST_DEBUG_FUNCPTR (gst_adder_release_pad); gstelement_class->change_state = GST_DEBUG_FUNCPTR (gst_adder_change_state); } static void gst_adder_init (GstAdder * adder) { GstPadTemplate *template; template = gst_static_pad_template_get (&gst_adder_src_template); adder->srcpad = gst_pad_new_from_template (template, "src"); gst_object_unref (template); gst_pad_set_getcaps_function (adder->srcpad, GST_DEBUG_FUNCPTR (gst_pad_proxy_getcaps)); gst_pad_set_setcaps_function (adder->srcpad, GST_DEBUG_FUNCPTR (gst_adder_setcaps)); gst_pad_set_query_function (adder->srcpad, GST_DEBUG_FUNCPTR (gst_adder_query)); gst_pad_set_event_function (adder->srcpad, GST_DEBUG_FUNCPTR (gst_adder_src_event)); gst_element_add_pad (GST_ELEMENT (adder), adder->srcpad); adder->format = GST_ADDER_FORMAT_UNSET; adder->padcount = 0; adder->func = NULL; /* keep track of the sinkpads requested */ adder->collect = gst_collect_pads_new (); gst_collect_pads_set_function (adder->collect, GST_DEBUG_FUNCPTR (gst_adder_collected), adder); } static void gst_adder_finalize (GObject * object) { GstAdder *adder = GST_ADDER (object); gst_object_unref (adder->collect); adder->collect = NULL; G_OBJECT_CLASS (parent_class)->finalize (object); } static GstPad * gst_adder_request_new_pad (GstElement * element, GstPadTemplate * templ, const gchar * unused) { gchar *name; GstAdder *adder; GstPad *newpad; gint padcount; if (templ->direction != GST_PAD_SINK) goto not_sink; adder = GST_ADDER (element); /* increment pad counter */ padcount = g_atomic_int_exchange_and_add (&adder->padcount, 1); name = g_strdup_printf ("sink%d", padcount); newpad = gst_pad_new_from_template (templ, name); GST_DEBUG_OBJECT (adder, "request new pad %s", name); g_free (name); gst_pad_set_getcaps_function (newpad, GST_DEBUG_FUNCPTR (gst_adder_sink_getcaps)); gst_pad_set_setcaps_function (newpad, GST_DEBUG_FUNCPTR (gst_adder_setcaps)); gst_collect_pads_add_pad (adder->collect, newpad, sizeof (GstCollectData)); /* FIXME: hacked way to override/extend the event function of * GstCollectPads; because it sets its own event function giving the * element no access to events */ adder->collect_event = (GstPadEventFunction) GST_PAD_EVENTFUNC (newpad); gst_pad_set_event_function (newpad, GST_DEBUG_FUNCPTR (gst_adder_sink_event)); /* takes ownership of the pad */ if (!gst_element_add_pad (GST_ELEMENT (adder), newpad)) goto could_not_add; return newpad; /* errors */ not_sink: { g_warning ("gstadder: request new pad that is not a SINK pad\n"); return NULL; } could_not_add: { GST_DEBUG_OBJECT (adder, "could not add pad"); gst_collect_pads_remove_pad (adder->collect, newpad); gst_object_unref (newpad); return NULL; } } static void gst_adder_release_pad (GstElement * element, GstPad * pad) { GstAdder *adder; adder = GST_ADDER (element); GST_DEBUG_OBJECT (adder, "release pad %s:%s", GST_DEBUG_PAD_NAME (pad)); gst_collect_pads_remove_pad (adder->collect, pad); gst_element_remove_pad (element, pad); } static GstFlowReturn gst_adder_collected (GstCollectPads * pads, gpointer user_data) { /* * combine channels by adding sample values * basic algorithm : * - this function is called when all pads have a buffer * - get available bytes on all pads. * - repeat for each input pad : * - read available bytes, copy or add to target buffer * - if there's an EOS event, remove the input channel * - push out the output buffer */ GstAdder *adder; guint size; GSList *collected; GstBuffer *outbuf; GstFlowReturn ret; gpointer outbytes; gboolean empty = TRUE; adder = GST_ADDER (user_data); /* this is fatal */ if (G_UNLIKELY (adder->func == NULL)) goto not_negotiated; /* get available bytes for reading, this can be 0 which could mean * empty buffers or EOS, which we will catch when we loop over the * pads. */ size = gst_collect_pads_available (pads); GST_LOG_OBJECT (adder, "starting to cycle through channels, %d bytes available (bps = %d)", size, adder->bps); outbuf = NULL; outbytes = NULL; for (collected = pads->data; collected; collected = g_slist_next (collected)) { GstCollectData *data; guint8 *bytes; guint len; GstBuffer *inbuf; data = (GstCollectData *) collected->data; /* get a subbuffer of size bytes */ inbuf = gst_collect_pads_take_buffer (pads, data, size); /* NULL means EOS or an empty buffer so we still need to flush in * case of an empty buffer. */ if (inbuf == NULL) { GST_LOG_OBJECT (adder, "channel %p: no bytes available", data); goto next; } bytes = GST_BUFFER_DATA (inbuf); len = GST_BUFFER_SIZE (inbuf); if (outbuf == NULL) { GST_LOG_OBJECT (adder, "channel %p: making output buffer of %d bytes", data, size); /* first buffer, alloc size bytes. FIXME, we can easily subbuffer * and _make_writable. */ outbuf = gst_buffer_new_and_alloc (size); outbytes = GST_BUFFER_DATA (outbuf); gst_buffer_set_caps (outbuf, GST_PAD_CAPS (adder->srcpad)); if (!GST_BUFFER_FLAG_IS_SET (inbuf, GST_BUFFER_FLAG_GAP)) { /* clear if we are only going to fill a partial buffer */ if (G_UNLIKELY (size > len)) memset (outbytes, 0, size); GST_LOG_OBJECT (adder, "channel %p: copying %d bytes from data %p", data, len, bytes); /* and copy the data into it */ memcpy (outbytes, bytes, len); empty = FALSE; } else { GST_LOG_OBJECT (adder, "channel %p: zeroing %d bytes from data %p", data, len, bytes); memset (outbytes, 0, size); } } else { if (!GST_BUFFER_FLAG_IS_SET (inbuf, GST_BUFFER_FLAG_GAP)) { GST_LOG_OBJECT (adder, "channel %p: mixing %d bytes from data %p", data, len, bytes); /* other buffers, need to add them */ adder->func ((gpointer) outbytes, (gpointer) bytes, len); empty = FALSE; } else { GST_LOG_OBJECT (adder, "channel %p: skipping %d bytes from data %p", data, len, bytes); } } next: if (inbuf) gst_buffer_unref (inbuf); } /* can only happen when no pads to collect or all EOS */ if (outbuf == NULL) goto eos; /* our timestamping is very simple, just an ever incrementing * counter, the new segment time will take care of their respective * stream time. */ if (adder->segment_pending) { GstEvent *event; /* FIXME, use rate/applied_rate as set on all sinkpads. * - currently we just set rate as received from last seek-event * We could potentially figure out the duration as well using * the current segment positions and the stated stop positions. * Also we just start from stream time 0 which is rather * weird. For non-synchronized mixing, the time should be * the min of the stream times of all received segments, * rationale being that the duration is at least going to * be as long as the earliest stream we start mixing. This * would also be correct for synchronized mixing but then * the later streams would be delayed until the stream times * match. */ event = gst_event_new_new_segment_full (FALSE, adder->segment_rate, 1.0, GST_FORMAT_TIME, adder->timestamp, -1, adder->segment_position); gst_pad_push_event (adder->srcpad, event); adder->segment_pending = FALSE; adder->segment_position = 0; } /* set timestamps on the output buffer */ GST_BUFFER_TIMESTAMP (outbuf) = adder->timestamp; GST_BUFFER_OFFSET (outbuf) = adder->offset; /* for the next timestamp, use the sample counter, which will * never accumulate rounding errors */ adder->offset += size / adder->bps; adder->timestamp = gst_util_uint64_scale_int (adder->offset, GST_SECOND, adder->rate); /* now we can set the duration of the buffer */ GST_BUFFER_DURATION (outbuf) = adder->timestamp - GST_BUFFER_TIMESTAMP (outbuf); /* if we only processed silence, mark output again as silence */ if (empty) GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_GAP); /* send it out */ GST_LOG_OBJECT (adder, "pushing outbuf, timestamp %" GST_TIME_FORMAT, GST_TIME_ARGS (GST_BUFFER_TIMESTAMP (outbuf))); ret = gst_pad_push (adder->srcpad, outbuf); return ret; /* ERRORS */ not_negotiated: { GST_ELEMENT_ERROR (adder, STREAM, FORMAT, (NULL), ("Unknown data received, not negotiated")); return GST_FLOW_NOT_NEGOTIATED; } eos: { GST_DEBUG_OBJECT (adder, "no data available, must be EOS"); gst_pad_push_event (adder->srcpad, gst_event_new_eos ()); return GST_FLOW_UNEXPECTED; } } static GstStateChangeReturn gst_adder_change_state (GstElement * element, GstStateChange transition) { GstAdder *adder; GstStateChangeReturn ret; adder = GST_ADDER (element); switch (transition) { case GST_STATE_CHANGE_NULL_TO_READY: break; case GST_STATE_CHANGE_READY_TO_PAUSED: adder->timestamp = 0; adder->offset = 0; adder->segment_pending = TRUE; adder->segment_position = 0; adder->segment_rate = 1.0; gst_segment_init (&adder->segment, GST_FORMAT_UNDEFINED); gst_collect_pads_start (adder->collect); break; case GST_STATE_CHANGE_PAUSED_TO_PLAYING: break; case GST_STATE_CHANGE_PAUSED_TO_READY: /* need to unblock the collectpads before calling the * parent change_state so that streaming can finish */ gst_collect_pads_stop (adder->collect); break; default: break; } ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition); switch (transition) { default: break; } return ret; } static gboolean plugin_init (GstPlugin * plugin) { if (!gst_element_register (plugin, "adder", GST_RANK_NONE, GST_TYPE_ADDER)) { return FALSE; } return TRUE; } GST_PLUGIN_DEFINE (GST_VERSION_MAJOR, GST_VERSION_MINOR, "adder", "Adds multiple streams", plugin_init, VERSION, "LGPL", GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN)