/* GStreamer * Copyright (C) <2006> Philippe Khalaf * * 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:gstbasertpaudiopayload * @short_description: Base class for audio RTP payloader * * * * Provides a base class for audio RTP payloaders for frame or sample based * audio codecs (constant bitrate) * * * This class derives from GstBaseRTPPayload. It can be used for payloading * audio codecs. It will only work with constant bitrate codecs. It supports * both frame based and sample based codecs. It takes care of packing up the * audio data into RTP packets and filling up the headers accordingly. The * payloading is done based on the maximum MTU (mtu) and the maximum time per * packet (max-ptime). The general idea is to divide large data buffers into * smaller RTP packets. The RTP packet size is the minimum of either the MTU, * max-ptime (if set) or available data. Any residual data is always sent in a * last RTP packet (no minimum RTP packet size). A minimum packet size might be * added in future versions if the need arises. In the case of frame * based codecs, the resulting RTP packets always contain full frames. * * Usage * * To use this base class, your child element needs to call either * gst_basertpaudiopayload_set_frame_based() or * gst_basertpaudiopayload_set_sample_based(). This is usually done in the * element's _init() function. Then, the child element must call either * gst_basertpaudiopayload_set_frame_options() or * gst_basertpaudiopayload_set_sample_options(). Since GstBaseRTPAudioPayload * derives from GstBaseRTPPayload, the child element must set any variables or * call/override any functions required by that base class. The child element * does not need to override any other functions specific to * GstBaseRTPAudioPayload. * * */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include #include #include "gstbasertpaudiopayload.h" GST_DEBUG_CATEGORY_STATIC (basertpaudiopayload_debug); #define GST_CAT_DEFAULT (basertpaudiopayload_debug) typedef enum { AUDIO_CODEC_TYPE_NONE, AUDIO_CODEC_TYPE_FRAME_BASED, AUDIO_CODEC_TYPE_SAMPLE_BASED } AudioCodecType; struct _GstBaseRTPAudioPayloadPrivate { AudioCodecType type; }; #define GST_BASE_RTP_AUDIO_PAYLOAD_GET_PRIVATE(o) \ (G_TYPE_INSTANCE_GET_PRIVATE ((o), GST_TYPE_BASE_RTP_AUDIO_PAYLOAD, \ GstBaseRTPAudioPayloadPrivate)) static void gst_base_rtp_audio_payload_finalize (GObject * object); static GstFlowReturn gst_base_rtp_audio_payload_push (GstBaseRTPPayload * basepayload, guint8 * data, guint payload_len, GstClockTime timestamp); static GstFlowReturn gst_base_rtp_audio_payload_handle_buffer (GstBaseRTPPayload * payload, GstBuffer * buffer); static GstFlowReturn gst_base_rtp_audio_payload_handle_frame_based_buffer (GstBaseRTPPayload * basepayload, GstBuffer * buffer); static GstFlowReturn gst_base_rtp_audio_payload_handle_sample_based_buffer (GstBaseRTPPayload * basepayload, GstBuffer * buffer); GST_BOILERPLATE (GstBaseRTPAudioPayload, gst_base_rtp_audio_payload, GstBaseRTPPayload, GST_TYPE_BASE_RTP_PAYLOAD); static void gst_base_rtp_audio_payload_base_init (gpointer klass) { } static void gst_base_rtp_audio_payload_class_init (GstBaseRTPAudioPayloadClass * klass) { GObjectClass *gobject_class; GstElementClass *gstelement_class; GstBaseRTPPayloadClass *gstbasertppayload_class; g_type_class_add_private (klass, sizeof (GstBaseRTPAudioPayloadPrivate)); gobject_class = (GObjectClass *) klass; gstelement_class = (GstElementClass *) klass; gstbasertppayload_class = (GstBaseRTPPayloadClass *) klass; gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_base_rtp_audio_payload_finalize); parent_class = g_type_class_ref (GST_TYPE_BASE_RTP_PAYLOAD); gstbasertppayload_class->handle_buffer = GST_DEBUG_FUNCPTR (gst_base_rtp_audio_payload_handle_buffer); GST_DEBUG_CATEGORY_INIT (basertpaudiopayload_debug, "basertpaudiopayload", 0, "base audio RTP payloader"); } static void gst_base_rtp_audio_payload_init (GstBaseRTPAudioPayload * basertpaudiopayload, GstBaseRTPAudioPayloadClass * klass) { basertpaudiopayload->priv = GST_BASE_RTP_AUDIO_PAYLOAD_GET_PRIVATE (basertpaudiopayload); basertpaudiopayload->base_ts = 0; basertpaudiopayload->priv->type = AUDIO_CODEC_TYPE_NONE; /* these need to be set by child object if frame based */ basertpaudiopayload->frame_size = 0; basertpaudiopayload->frame_duration = 0; /* these need to be set by child object if sample based */ basertpaudiopayload->sample_size = 0; } static void gst_base_rtp_audio_payload_finalize (GObject * object) { GstBaseRTPAudioPayload *basertpaudiopayload; basertpaudiopayload = GST_BASE_RTP_AUDIO_PAYLOAD (object); GST_CALL_PARENT (G_OBJECT_CLASS, finalize, (object)); } /** * gst_base_rtp_audio_payload_set_frame_based: * @basertpaudiopayload: a pointer to the element. * * Tells #GstBaseRTPAudioPayload that the child element is for a frame based * audio codec * */ void gst_base_rtp_audio_payload_set_frame_based (GstBaseRTPAudioPayload * basertpaudiopayload) { g_return_if_fail (basertpaudiopayload != NULL); g_return_if_fail (basertpaudiopayload->priv->type == AUDIO_CODEC_TYPE_NONE); basertpaudiopayload->priv->type = AUDIO_CODEC_TYPE_FRAME_BASED; } /** * gst_base_rtp_audio_payload_set_sample_based: * @basertpaudiopayload: a pointer to the element. * * Tells #GstBaseRTPAudioPayload that the child element is for a sample based * audio codec * */ void gst_base_rtp_audio_payload_set_sample_based (GstBaseRTPAudioPayload * basertpaudiopayload) { g_return_if_fail (basertpaudiopayload != NULL); g_return_if_fail (basertpaudiopayload->priv->type == AUDIO_CODEC_TYPE_NONE); basertpaudiopayload->priv->type = AUDIO_CODEC_TYPE_SAMPLE_BASED; } /** * gst_base_rtp_audio_payload_set_frame_options: * @basertpaudiopayload: a pointer to the element. * @frame_duration: The duraction of an audio frame in milliseconds. * @frame_size: The size of an audio frame in bytes. * * Sets the options for frame based audio codecs. * */ void gst_base_rtp_audio_payload_set_frame_options (GstBaseRTPAudioPayload * basertpaudiopayload, gint frame_duration, gint frame_size) { g_return_if_fail (basertpaudiopayload != NULL); basertpaudiopayload->frame_size = frame_size; basertpaudiopayload->frame_duration = frame_duration; } /** * gst_base_rtp_audio_payload_set_sample_options: * @basertpaudiopayload: a pointer to the element. * @sample_size: Size per sample in bytes. * * Sets the options for sample based audio codecs. * */ void gst_base_rtp_audio_payload_set_sample_options (GstBaseRTPAudioPayload * basertpaudiopayload, gint sample_size) { g_return_if_fail (basertpaudiopayload != NULL); basertpaudiopayload->sample_size = sample_size; } static GstFlowReturn gst_base_rtp_audio_payload_handle_buffer (GstBaseRTPPayload * basepayload, GstBuffer * buffer) { GstFlowReturn ret; GstBaseRTPAudioPayload *basertpaudiopayload; basertpaudiopayload = GST_BASE_RTP_AUDIO_PAYLOAD (basepayload); ret = GST_FLOW_ERROR; if (basertpaudiopayload->priv->type == AUDIO_CODEC_TYPE_FRAME_BASED) { ret = gst_base_rtp_audio_payload_handle_frame_based_buffer (basepayload, buffer); } else if (basertpaudiopayload->priv->type == AUDIO_CODEC_TYPE_SAMPLE_BASED) { ret = gst_base_rtp_audio_payload_handle_sample_based_buffer (basepayload, buffer); } else { GST_DEBUG_OBJECT (basertpaudiopayload, "Audio codec type not set"); } return ret; } /* this assumes all frames have a constant duration and a constant size */ static GstFlowReturn gst_base_rtp_audio_payload_handle_frame_based_buffer (GstBaseRTPPayload * basepayload, GstBuffer * buffer) { GstBaseRTPAudioPayload *basertpaudiopayload; guint payload_len; guint8 *data; GstFlowReturn ret; guint available; gint frame_size, frame_duration; guint maxptime_octets = G_MAXUINT; ret = GST_FLOW_ERROR; basertpaudiopayload = GST_BASE_RTP_AUDIO_PAYLOAD (basepayload); if (basertpaudiopayload->frame_size == 0 || basertpaudiopayload->frame_duration == 0) { GST_DEBUG_OBJECT (basertpaudiopayload, "Required options not set"); gst_buffer_unref (buffer); return GST_FLOW_ERROR; } frame_size = basertpaudiopayload->frame_size; frame_duration = basertpaudiopayload->frame_duration; /* If buffer fits on an RTP packet, let's just push it through */ /* this will check against max_ptime and max_mtu */ if (!gst_basertppayload_is_filled (basepayload, gst_rtp_buffer_calc_packet_len (GST_BUFFER_SIZE (buffer), 0, 0), GST_BUFFER_DURATION (buffer))) { ret = gst_base_rtp_audio_payload_push (basepayload, GST_BUFFER_DATA (buffer), GST_BUFFER_SIZE (buffer), GST_BUFFER_TIMESTAMP (buffer)); gst_buffer_unref (buffer); return ret; } /* max number of bytes based on given ptime, has to be multiple of * frame_duration */ if (basepayload->max_ptime != -1) { guint ptime_ms = basepayload->max_ptime / 1000000; maxptime_octets = frame_size * (int) (ptime_ms / frame_duration); if (maxptime_octets == 0) { GST_WARNING_OBJECT (basertpaudiopayload, "Given ptime %d is smaller than" " minimum %d ms, overwriting to minimum", ptime_ms, frame_duration); maxptime_octets = frame_size; } } /* let's set the base timestamp */ basertpaudiopayload->base_ts = GST_BUFFER_TIMESTAMP (buffer); available = GST_BUFFER_SIZE (buffer); data = (guint8 *) GST_BUFFER_DATA (buffer); /* as long as we have full frames */ /* this loop will push all available buffers till the last frame */ while (available >= frame_size) { /* we need to see how many frames we can get based on maximum MTU, maximum * ptime and the number of bytes available */ payload_len = MIN (MIN ( /* MTU max */ (int) (gst_rtp_buffer_calc_payload_len (GST_BASE_RTP_PAYLOAD_MTU (basertpaudiopayload), 0, 0) / frame_size) * frame_size, /* ptime max */ maxptime_octets), /* currently available */ (available / frame_size) * frame_size); ret = gst_base_rtp_audio_payload_push (basepayload, data, payload_len, basertpaudiopayload->base_ts); gfloat ts_inc = (payload_len * frame_duration) / frame_size; ts_inc = ts_inc * GST_MSECOND; basertpaudiopayload->base_ts += ts_inc; available -= payload_len; data += payload_len; } gst_buffer_unref (buffer); /* none should be available by now */ if (available != 0) { GST_ERROR_OBJECT (basertpaudiopayload, "The buffer size is not a multiple" " of the frame_size"); return GST_FLOW_ERROR; } return ret; } static GstFlowReturn gst_base_rtp_audio_payload_handle_sample_based_buffer (GstBaseRTPPayload * basepayload, GstBuffer * buffer) { GstBaseRTPAudioPayload *basertpaudiopayload; guint payload_len; guint8 *data; GstFlowReturn ret; guint available; guint maxptime_octets = G_MAXUINT; guint sample_size; ret = GST_FLOW_ERROR; basertpaudiopayload = GST_BASE_RTP_AUDIO_PAYLOAD (basepayload); if (basertpaudiopayload->sample_size == 0) { GST_DEBUG_OBJECT (basertpaudiopayload, "Required options not set"); gst_buffer_unref (buffer); return GST_FLOW_ERROR; } sample_size = basertpaudiopayload->sample_size; /* If buffer fits on an RTP packet, let's just push it through */ /* this will check against max_ptime and max_mtu */ if (!gst_basertppayload_is_filled (basepayload, gst_rtp_buffer_calc_packet_len (GST_BUFFER_SIZE (buffer), 0, 0), GST_BUFFER_DURATION (buffer))) { ret = gst_base_rtp_audio_payload_push (basepayload, GST_BUFFER_DATA (buffer), GST_BUFFER_SIZE (buffer), GST_BUFFER_TIMESTAMP (buffer)); gst_buffer_unref (buffer); return ret; } /* max number of bytes based on given ptime */ if (basepayload->max_ptime != -1) { maxptime_octets = basepayload->max_ptime * basepayload->clock_rate / (sample_size * GST_SECOND); GST_DEBUG_OBJECT (basertpaudiopayload, "Calculated max_octects %u", maxptime_octets); } /* let's set the base timestamp */ basertpaudiopayload->base_ts = GST_BUFFER_TIMESTAMP (buffer); GST_DEBUG_OBJECT (basertpaudiopayload, "Setting to %" GST_TIME_FORMAT, GST_TIME_ARGS (GST_BUFFER_TIMESTAMP (buffer))); available = GST_BUFFER_SIZE (buffer); data = (guint8 *) GST_BUFFER_DATA (buffer); /* as long as we have full frames */ /* this loop will use all available data until the last byte */ while (available) { /* we need to see how many frames we can get based on maximum MTU, maximum * ptime and the number of bytes available */ payload_len = MIN (MIN ( /* MTU max */ gst_rtp_buffer_calc_payload_len (GST_BASE_RTP_PAYLOAD_MTU (basertpaudiopayload), 0, 0), /* ptime max */ maxptime_octets), /* currently available */ available); ret = gst_base_rtp_audio_payload_push (basepayload, data, payload_len, basertpaudiopayload->base_ts); gfloat num = payload_len; gfloat datarate = (sample_size * basepayload->clock_rate); basertpaudiopayload->base_ts += /* payload_len (bytes) * nsecs/sec / datarate (bytes*sec) */ num / datarate * GST_SECOND; GST_DEBUG_OBJECT (basertpaudiopayload, "New ts is %" GST_TIME_FORMAT, GST_TIME_ARGS (basertpaudiopayload->base_ts)); available -= payload_len; data += payload_len; } gst_buffer_unref (buffer); return ret; } static GstFlowReturn gst_base_rtp_audio_payload_push (GstBaseRTPPayload * basepayload, guint8 * data, guint payload_len, GstClockTime timestamp) { GstBuffer *outbuf; guint8 *payload; GstFlowReturn ret; GST_DEBUG_OBJECT (basepayload, "Pushing %d bytes ts %" GST_TIME_FORMAT, payload_len, GST_TIME_ARGS (timestamp)); /* create buffer to hold the payload */ outbuf = gst_rtp_buffer_new_allocate (payload_len, 0, 0); /* copy payload */ gst_rtp_buffer_set_payload_type (outbuf, basepayload->pt); payload = gst_rtp_buffer_get_payload (outbuf); memcpy (payload, data, payload_len); GST_BUFFER_TIMESTAMP (outbuf) = timestamp; ret = gst_basertppayload_push (basepayload, outbuf); return ret; }