gstreamer/gst/rtp/gstrtpL16enc.c

/* GStreamer
 * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
 *
 * 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.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include <stdlib.h>
#include "gstrtpL16enc.h"

/* elementfactory information */
static GstElementDetails gst_rtpL16enc_details = {
  "RTP RAW Audio Encoder",
  "Codec/Encoder/Network",
  "Encodes Raw Audio into a RTP packet",
  "Zeeshan Ali <zak147@yahoo.com>"
};

/* RtpL16Enc signals and args */
enum
{
  /* FILL ME */
  LAST_SIGNAL
};

enum
{
  /* FILL ME */
  ARG_0
};

static GstStaticPadTemplate gst_rtpL16enc_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
    GST_PAD_SINK,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS ("audio/x-raw-int, "
        "endianness = (int) BYTE_ORDER, "
        "signed = (boolean) true, "
        "width = (int) 16, "
        "depth = (int) 16, "
        "rate = (int) [ 1000, 48000 ], " "channels = (int) [ 1, 2 ]")
    );

static GstStaticPadTemplate gst_rtpL16enc_src_template =
GST_STATIC_PAD_TEMPLATE ("src",
    GST_PAD_SRC,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS ("application/x-rtp")
    );

static void gst_rtpL16enc_class_init (GstRtpL16EncClass * klass);
static void gst_rtpL16enc_base_init (GstRtpL16EncClass * klass);
static void gst_rtpL16enc_init (GstRtpL16Enc * rtpL16enc);
static void gst_rtpL16enc_chain (GstPad * pad, GstData * _data);
static void gst_rtpL16enc_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec);
static void gst_rtpL16enc_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec);
static GstPadLinkReturn gst_rtpL16enc_sinkconnect (GstPad * pad,
    const GstCaps * caps);
static GstStateChangeReturn gst_rtpL16enc_change_state (GstElement * element,
    GstStateChange transition);

static GstElementClass *parent_class = NULL;

static GType
gst_rtpL16enc_get_type (void)
{
  static GType rtpL16enc_type = 0;

  if (!rtpL16enc_type) {
    static const GTypeInfo rtpL16enc_info = {
      sizeof (GstRtpL16EncClass),
      (GBaseInitFunc) gst_rtpL16enc_base_init,
      NULL,
      (GClassInitFunc) gst_rtpL16enc_class_init,
      NULL,
      NULL,
      sizeof (GstRtpL16Enc),
      0,
      (GInstanceInitFunc) gst_rtpL16enc_init,
    };

    rtpL16enc_type =
        g_type_register_static (GST_TYPE_ELEMENT, "GstRtpL16Enc",
        &rtpL16enc_info, 0);
  }
  return rtpL16enc_type;
}

static void
gst_rtpL16enc_base_init (GstRtpL16EncClass * klass)
{
  GstElementClass *element_class = GST_ELEMENT_CLASS (klass);

  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&gst_rtpL16enc_sink_template));
  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&gst_rtpL16enc_src_template));
  gst_element_class_set_details (element_class, &gst_rtpL16enc_details);
}

static void
gst_rtpL16enc_class_init (GstRtpL16EncClass * klass)
{
  GObjectClass *gobject_class;
  GstElementClass *gstelement_class;

  gobject_class = (GObjectClass *) klass;
  gstelement_class = (GstElementClass *) klass;

  parent_class = g_type_class_ref (GST_TYPE_ELEMENT);

  gobject_class->set_property = gst_rtpL16enc_set_property;
  gobject_class->get_property = gst_rtpL16enc_get_property;

  gstelement_class->change_state = gst_rtpL16enc_change_state;
}

static void
gst_rtpL16enc_init (GstRtpL16Enc * rtpL16enc)
{
  rtpL16enc->sinkpad =
      gst_pad_new_from_template (gst_static_pad_template_get
      (&gst_rtpL16enc_sink_template), "sink");
  rtpL16enc->srcpad =
      gst_pad_new_from_template (gst_static_pad_template_get
      (&gst_rtpL16enc_src_template), "src");
  gst_element_add_pad (GST_ELEMENT (rtpL16enc), rtpL16enc->sinkpad);
  gst_element_add_pad (GST_ELEMENT (rtpL16enc), rtpL16enc->srcpad);
  gst_pad_set_chain_function (rtpL16enc->sinkpad, gst_rtpL16enc_chain);
  gst_pad_set_link_function (rtpL16enc->sinkpad, gst_rtpL16enc_sinkconnect);

  rtpL16enc->frequency = 44100;
  rtpL16enc->channels = 2;

  rtpL16enc->next_time = 0;
  rtpL16enc->time_interval = 0;

  rtpL16enc->seq = 0;
  rtpL16enc->ssrc = random ();
}

static GstPadLinkReturn
gst_rtpL16enc_sinkconnect (GstPad * pad, const GstCaps * caps)
{
  GstRtpL16Enc *rtpL16enc;
  GstStructure *structure;
  gboolean ret;

  rtpL16enc = GST_RTP_L16_ENC (gst_pad_get_parent (pad));

  structure = gst_caps_get_structure (caps, 0);

  ret = gst_structure_get_int (structure, "rate", &rtpL16enc->frequency);
  ret &= gst_structure_get_int (structure, "channels", &rtpL16enc->channels);

  if (!ret)
    return GST_PAD_LINK_REFUSED;

  /* Pre-calculate what we can */
  rtpL16enc->time_interval =
      GST_SECOND / (2 * rtpL16enc->channels * rtpL16enc->frequency);

  return GST_PAD_LINK_OK;
}


void
gst_rtpL16enc_htons (GstBuffer * buf)
{
  gint16 *i, *len;

  /* FIXME: is this code correct or even sane at all? */
  i = (gint16 *) GST_BUFFER_DATA (buf);
  len = i + GST_BUFFER_SIZE (buf) / sizeof (gint16 *);

  for (; i < len; i++) {
    *i = g_htons (*i);
  }
}

static void
gst_rtpL16enc_chain (GstPad * pad, GstData * _data)
{
  GstBuffer *buf = GST_BUFFER (_data);
  GstRtpL16Enc *rtpL16enc;
  GstBuffer *outbuf;
  Rtp_Packet packet;

  g_return_if_fail (pad != NULL);
  g_return_if_fail (GST_IS_PAD (pad));
  g_return_if_fail (buf != NULL);

  rtpL16enc = GST_RTP_L16_ENC (GST_OBJECT_PARENT (pad));

  g_return_if_fail (rtpL16enc != NULL);
  g_return_if_fail (GST_IS_RTP_L16_ENC (rtpL16enc));

  if (GST_IS_EVENT (buf)) {
    GstEvent *event = GST_EVENT (buf);

    switch (GST_EVENT_TYPE (event)) {
      case GST_EVENT_DISCONTINUOUS:
        GST_DEBUG ("discont");
        rtpL16enc->next_time = 0;
        gst_pad_event_default (pad, event);
        return;
      default:
        gst_pad_event_default (pad, event);
        return;
    }
  }

  /* We only need the header */
  packet = rtp_packet_new_allocate (0, 0, 0);

  rtp_packet_set_csrc_count (packet, 0);
  rtp_packet_set_extension (packet, 0);
  rtp_packet_set_padding (packet, 0);
  rtp_packet_set_version (packet, RTP_VERSION);
  rtp_packet_set_marker (packet, 0);
  rtp_packet_set_ssrc (packet, g_htonl (rtpL16enc->ssrc));
  rtp_packet_set_seq (packet, g_htons (rtpL16enc->seq));
  rtp_packet_set_timestamp (packet,
      g_htonl ((guint32) rtpL16enc->next_time / GST_SECOND));

  if (rtpL16enc->channels == 1) {
    rtp_packet_set_payload_type (packet, (guint8) PAYLOAD_L16_MONO);
  }

  else {
    rtp_packet_set_payload_type (packet, (guint8) PAYLOAD_L16_STEREO);
  }

  /* FIXME: According to RFC 1890, this is required, right? */
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
  gst_rtpL16enc_htons (buf);
#endif

  outbuf = gst_buffer_new ();
  GST_BUFFER_SIZE (outbuf) =
      rtp_packet_get_packet_len (packet) + GST_BUFFER_SIZE (buf);
  GST_BUFFER_DATA (outbuf) = g_malloc (GST_BUFFER_SIZE (outbuf));
  GST_BUFFER_TIMESTAMP (outbuf) = rtpL16enc->next_time;

  memcpy (GST_BUFFER_DATA (outbuf), packet->data,
      rtp_packet_get_packet_len (packet));
  memcpy (GST_BUFFER_DATA (outbuf) + rtp_packet_get_packet_len (packet),
      GST_BUFFER_DATA (buf), GST_BUFFER_SIZE (buf));

  GST_DEBUG ("gst_rtpL16enc_chain: pushing buffer of size %d",
      GST_BUFFER_SIZE (outbuf));
  gst_pad_push (rtpL16enc->srcpad, GST_DATA (outbuf));

  ++rtpL16enc->seq;
  rtpL16enc->next_time += rtpL16enc->time_interval * GST_BUFFER_SIZE (buf);

  rtp_packet_free (packet);
  gst_buffer_unref (buf);
}

static void
gst_rtpL16enc_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstRtpL16Enc *rtpL16enc;

  g_return_if_fail (GST_IS_RTP_L16_ENC (object));
  rtpL16enc = GST_RTP_L16_ENC (object);

  switch (prop_id) {
    default:
      break;
  }
}

static void
gst_rtpL16enc_get_property (GObject * object, guint prop_id, GValue * value,
    GParamSpec * pspec)
{
  GstRtpL16Enc *rtpL16enc;

  g_return_if_fail (GST_IS_RTP_L16_ENC (object));
  rtpL16enc = GST_RTP_L16_ENC (object);

  switch (prop_id) {
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static GstStateChangeReturn
gst_rtpL16enc_change_state (GstElement * element, GstStateChange transition)
{
  GstRtpL16Enc *rtpL16enc;

  g_return_val_if_fail (GST_IS_RTP_L16_ENC (element), GST_STATE_CHANGE_FAILURE);

  rtpL16enc = GST_RTP_L16_ENC (element);

  GST_DEBUG ("state pending %d\n", GST_STATE_PENDING (element));

  /* if going down into NULL state, close the file if it's open */
  switch (transition) {
    case GST_STATE_CHANGE_NULL_TO_READY:
      break;

    case GST_STATE_CHANGE_READY_TO_NULL:
      break;

    default:
      break;
  }

  /* if we haven't failed already, give the parent class a chance to ;-) */
  if (GST_ELEMENT_CLASS (parent_class)->change_state)
    return GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);

  return GST_STATE_CHANGE_SUCCESS;
}

gboolean
gst_rtpL16enc_plugin_init (GstPlugin * plugin)
{
  return gst_element_register (plugin, "rtpL16enc",
      GST_RANK_NONE, GST_TYPE_RTP_L16_ENC);
}