diff options
Diffstat (limited to 'gst/rtp/gstrtpsbcdepay.c')
-rwxr-xr-x | gst/rtp/gstrtpsbcdepay.c | 287 |
1 files changed, 287 insertions, 0 deletions
diff --git a/gst/rtp/gstrtpsbcdepay.c b/gst/rtp/gstrtpsbcdepay.c new file mode 100755 index 0000000..28c00fc --- /dev/null +++ b/gst/rtp/gstrtpsbcdepay.c @@ -0,0 +1,287 @@ +/* + * GStreamer RTP SBC depayloader + * + * Copyright (C) 2012 Collabora Ltd. + * @author: Arun Raghavan <arun.raghavan@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., 51 Franklin St, Fifth Floor, + * Boston, MA 02110-1301, USA. + */ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include <gst/rtp/gstrtpbuffer.h> +#include "gstrtpsbcdepay.h" + +GST_DEBUG_CATEGORY_STATIC (rtpsbcdepay_debug); +#define GST_CAT_DEFAULT (rtpsbcdepay_debug) + +static GstStaticPadTemplate gst_rtp_sbc_depay_src_template = +GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS, + GST_STATIC_CAPS ("audio/x-sbc, " + "rate = (int) { 16000, 32000, 44100, 48000 }, " + "channels = (int) [ 1, 2 ], " + "mode = (string) { mono, dual, stereo, joint }, " + "blocks = (int) { 4, 8, 12, 16 }, " + "subbands = (int) { 4, 8 }, " + "allocation-method = (string) { snr, loudness }, " + "bitpool = (int) [ 2, 64 ]") + ); + +static GstStaticPadTemplate gst_rtp_sbc_depay_sink_template = +GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS, + GST_STATIC_CAPS ("application/x-rtp, " + "media = (string) audio," + "payload = (int) " GST_RTP_PAYLOAD_DYNAMIC_STRING ", " + "clock-rate = (int) { 16000, 32000, 44100, 48000 }," + "encoding-name = (string) SBC") + ); + +#define gst_rtp_sbc_depay_parent_class parent_class +G_DEFINE_TYPE (GstRtpSbcDepay, gst_rtp_sbc_depay, GST_TYPE_RTP_BASE_DEPAYLOAD); + +static void gst_rtp_sbc_depay_finalize (GObject * object); + +static gboolean gst_rtp_sbc_depay_setcaps (GstRTPBaseDepayload * base, + GstCaps * caps); +static GstBuffer *gst_rtp_sbc_depay_process (GstRTPBaseDepayload * base, + GstBuffer * in); + +static void +gst_rtp_sbc_depay_class_init (GstRtpSbcDepayClass * klass) +{ + GstRTPBaseDepayloadClass *gstbasertpdepayload_class = + GST_RTP_BASE_DEPAYLOAD_CLASS (klass); + GstElementClass *element_class = GST_ELEMENT_CLASS (klass); + GObjectClass *gobject_class = G_OBJECT_CLASS (klass); + + gobject_class->finalize = gst_rtp_sbc_depay_finalize; + + gstbasertpdepayload_class->set_caps = gst_rtp_sbc_depay_setcaps; + gstbasertpdepayload_class->process = gst_rtp_sbc_depay_process; + + gst_element_class_add_pad_template (element_class, + gst_static_pad_template_get (&gst_rtp_sbc_depay_src_template)); + gst_element_class_add_pad_template (element_class, + gst_static_pad_template_get (&gst_rtp_sbc_depay_sink_template)); + + GST_DEBUG_CATEGORY_INIT (rtpsbcdepay_debug, "rtpsbcdepay", 0, + "SBC Audio RTP Depayloader"); + + gst_element_class_set_static_metadata (element_class, + "RTP SBC audio depayloader", + "Codec/Depayloader/Network/RTP", + "Extracts SBC audio from RTP packets", + "Arun Raghavan <arun.raghavan@collabora.co.uk>"); +} + +static void +gst_rtp_sbc_depay_init (GstRtpSbcDepay * rtpsbcdepay) +{ + rtpsbcdepay->adapter = gst_adapter_new (); +} + +static void +gst_rtp_sbc_depay_finalize (GObject * object) +{ + GstRtpSbcDepay *depay = GST_RTP_SBC_DEPAY (object); + + gst_object_unref (depay->adapter); + + G_OBJECT_CLASS (parent_class)->finalize (object); +} + +/* FIXME: This duplicates similar functionality rtpsbcpay, but there isn't a + * simple way to consolidate the two. This is best done by moving the function + * to the codec-utils library in gst-plugins-base when these elements move to + * GStreamer. */ +static int +gst_rtp_sbc_depay_get_params (GstRtpSbcDepay * depay, const guint8 * data, + gint size, int *framelen, int *samples) +{ + int blocks, channel_mode, channels, subbands, bitpool; + int length; + + if (size < 3) { + /* Not enough data for the header */ + return -1; + } + + /* Sanity check */ + if (data[0] != 0x9c) { + GST_WARNING_OBJECT (depay, "Bad packet: couldn't find syncword"); + return -2; + } + + blocks = (data[1] >> 4) & 0x3; + blocks = (blocks + 1) * 4; + channel_mode = (data[1] >> 2) & 0x3; + channels = channel_mode ? 2 : 1; + subbands = (data[1] & 0x1); + subbands = (subbands + 1) * 4; + bitpool = data[2]; + + length = 4 + ((4 * subbands * channels) / 8); + + if (channel_mode == 0 || channel_mode == 1) { + /* Mono || Dual channel */ + length += ((blocks * channels * bitpool) + + 4 /* round up */ ) / 8; + } else { + /* Stereo || Joint stereo */ + gboolean joint = (channel_mode == 3); + + length += ((joint * subbands) + (blocks * bitpool) + + 4 /* round up */ ) / 8; + } + + *framelen = length; + *samples = blocks * subbands; + + return 0; +} + +static gboolean +gst_rtp_sbc_depay_setcaps (GstRTPBaseDepayload * base, GstCaps * caps) +{ + GstRtpSbcDepay *depay = GST_RTP_SBC_DEPAY (base); + GstStructure *structure; + GstCaps *outcaps, *oldcaps; + + structure = gst_caps_get_structure (caps, 0); + + if (!gst_structure_get_int (structure, "clock-rate", &depay->rate)) + goto bad_caps; + + outcaps = gst_caps_new_simple ("audio/x-sbc", "rate", G_TYPE_INT, + depay->rate, NULL); + + gst_pad_set_caps (GST_RTP_BASE_DEPAYLOAD_SRCPAD (base), outcaps); + + oldcaps = gst_pad_get_current_caps (GST_RTP_BASE_DEPAYLOAD_SINKPAD (base)); + if (oldcaps && !gst_caps_can_intersect (oldcaps, caps)) { + /* Caps have changed, flush old data */ + gst_adapter_clear (depay->adapter); + } + + gst_caps_unref (outcaps); + + return TRUE; + +bad_caps: + GST_WARNING_OBJECT (depay, "Can't support the caps we got: %" + GST_PTR_FORMAT, caps); + return FALSE; +} + +static GstBuffer * +gst_rtp_sbc_depay_process (GstRTPBaseDepayload * base, GstBuffer * in) +{ + GstRtpSbcDepay *depay = GST_RTP_SBC_DEPAY (base); + GstBuffer *data = NULL; + GstRTPBuffer rtp = { NULL }; + + gboolean fragment, start, last; + guint8 nframes; + guint8 *payload; + guint payload_len; + + gst_rtp_buffer_map (in, GST_MAP_READ, &rtp); + + GST_LOG_OBJECT (depay, "Got %" G_GSIZE_FORMAT " bytes", + gst_buffer_get_size (in)); + + if (gst_rtp_buffer_get_marker (&rtp)) { + /* Marker isn't supposed to be set */ + GST_WARNING_OBJECT (depay, "Marker bit was set"); + goto bad_packet; + } + + payload = gst_rtp_buffer_get_payload (&rtp); + payload_len = gst_rtp_buffer_get_payload_len (&rtp); + + fragment = payload[0] & 0x80; + start = payload[0] & 0x40; + last = payload[0] & 0x20; + nframes = payload[0] & 0x0f; + + payload += 1; + payload_len -= 1; + + data = gst_rtp_buffer_get_payload_subbuffer (&rtp, 1, -1); + + if (fragment) { + /* Got a packet with a fragment */ + GST_LOG_OBJECT (depay, "Got fragment"); + + if (start && gst_adapter_available (depay->adapter)) { + GST_WARNING_OBJECT (depay, "Missing last fragment"); + gst_adapter_clear (depay->adapter); + + } else if (!start && !gst_adapter_available (depay->adapter)) { + GST_WARNING_OBJECT (depay, "Missing start fragment"); + gst_buffer_unref (data); + data = NULL; + goto out; + } + + gst_adapter_push (depay->adapter, data); + + if (last) { + data = gst_adapter_take_buffer (depay->adapter, + gst_adapter_available (depay->adapter)); + } else + data = NULL; + + } else { + /* !fragment */ + gint framelen, samples; + + GST_LOG_OBJECT (depay, "Got %d frames", nframes); + + if (gst_rtp_sbc_depay_get_params (depay, payload, + payload_len, &framelen, &samples) < 0) { + gst_adapter_clear (depay->adapter); + goto bad_packet; + } + + GST_LOG_OBJECT (depay, "Got payload of %d", payload_len); + + if (nframes * framelen > (gint) payload_len) { + GST_WARNING_OBJECT (depay, "Short packet"); + goto bad_packet; + } else if (nframes * framelen < (gint) payload_len) { + GST_WARNING_OBJECT (depay, "Junk at end of packet"); + } + } + +out: + gst_rtp_buffer_unmap (&rtp); + return data; + +bad_packet: + GST_ELEMENT_WARNING (depay, STREAM, DECODE, + ("Received invalid RTP payload, dropping"), (NULL)); + goto out; +} + +gboolean +gst_rtp_sbc_depay_plugin_init (GstPlugin * plugin) +{ + return gst_element_register (plugin, "rtpsbcdepay", GST_RANK_SECONDARY, + GST_TYPE_RTP_SBC_DEPAY); +} |