--- /dev/null
+/* GStreamer
+ * Copyright (C) <2010> Mark Nauwelaerts <mark.nauwelaerts@collabora.co.uk>
+ * Copyright (C) <2010> Nokia Corporation
+ *
+ * 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 <gst/rtp/gstrtpbuffer.h>
+
+#include <string.h>
+#include "gstrtpmparobustdepay.h"
+
+GST_DEBUG_CATEGORY_STATIC (rtpmparobustdepay_debug);
+#define GST_CAT_DEFAULT (rtpmparobustdepay_debug)
+
+static GstStaticPadTemplate gst_rtp_mpa_robust_depay_src_template =
+GST_STATIC_PAD_TEMPLATE ("src",
+ GST_PAD_SRC,
+ GST_PAD_ALWAYS,
+ GST_STATIC_CAPS ("audio/mpeg, " "mpegversion = (int) 1")
+ );
+
+static GstStaticPadTemplate gst_rtp_mpa_robust_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) 90000, "
+ "encoding-name = (string) \"MPA-ROBUST\" " "; "
+ /* draft versions appear still in use out there */
+ "application/x-rtp, "
+ "media = (string) \"audio\", "
+ "payload = (int) " GST_RTP_PAYLOAD_DYNAMIC_STRING ", "
+ "clock-rate = (int) [1, MAX], "
+ "encoding-name = (string) { \"X-MP3-DRAFT-00\", \"X-MP3-DRAFT-01\", "
+ " \"X-MP3-DRAFT-02\", \"X-MP3-DRAFT-03\", \"X-MP3-DRAFT-04\", "
+ " \"X-MP3-DRAFT-05\", \"X-MP3-DRAFT-06\" }")
+ );
+
+typedef struct _GstADUFrame
+{
+ guint32 header;
+ gint size;
+ gint side_info;
+ gint data_size;
+ gint layer;
+ gint backpointer;
+
+ GstBuffer *buffer;
+} GstADUFrame;
+
+GST_BOILERPLATE (GstRtpMPARobustDepay, gst_rtp_mpa_robust_depay,
+ GstBaseRTPDepayload, GST_TYPE_BASE_RTP_DEPAYLOAD);
+
+static GstStateChangeReturn gst_rtp_mpa_robust_change_state (GstElement *
+ element, GstStateChange transition);
+
+static gboolean gst_rtp_mpa_robust_depay_setcaps (GstBaseRTPDepayload *
+ depayload, GstCaps * caps);
+static GstBuffer *gst_rtp_mpa_robust_depay_process (GstBaseRTPDepayload *
+ depayload, GstBuffer * buf);
+
+static void
+gst_rtp_mpa_robust_depay_base_init (gpointer klass)
+{
+ GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
+
+ gst_element_class_add_pad_template (element_class,
+ gst_static_pad_template_get (&gst_rtp_mpa_robust_depay_src_template));
+ gst_element_class_add_pad_template (element_class,
+ gst_static_pad_template_get (&gst_rtp_mpa_robust_depay_sink_template));
+
+ gst_element_class_set_details_simple (element_class,
+ "RTP MPEG audio depayloader", "Codec/Depayloader/Network",
+ "Extracts MPEG audio from RTP packets (RFC 5219)",
+ "Mark Nauwelaerts <mark.nauwelaerts@collabora.co.uk>");
+}
+
+static void
+gst_rtp_mpa_robust_depay_finalize (GObject * object)
+{
+ GstRtpMPARobustDepay *rtpmpadepay;
+
+ rtpmpadepay = (GstRtpMPARobustDepay *) object;
+
+ g_object_unref (rtpmpadepay->adapter);
+ g_queue_free (rtpmpadepay->adu_frames);
+
+ G_OBJECT_CLASS (parent_class)->finalize (object);
+}
+
+
+static void
+gst_rtp_mpa_robust_depay_class_init (GstRtpMPARobustDepayClass * klass)
+{
+ GObjectClass *gobject_class;
+ GstElementClass *gstelement_class;
+ GstBaseRTPDepayloadClass *gstbasertpdepayload_class;
+
+ gobject_class = (GObjectClass *) klass;
+ gstelement_class = (GstElementClass *) klass;
+ gstbasertpdepayload_class = (GstBaseRTPDepayloadClass *) klass;
+
+ gobject_class->finalize = gst_rtp_mpa_robust_depay_finalize;
+
+ gstelement_class->change_state =
+ GST_DEBUG_FUNCPTR (gst_rtp_mpa_robust_change_state);
+
+ gstbasertpdepayload_class->set_caps = gst_rtp_mpa_robust_depay_setcaps;
+ gstbasertpdepayload_class->process = gst_rtp_mpa_robust_depay_process;
+
+ GST_DEBUG_CATEGORY_INIT (rtpmparobustdepay_debug, "rtpmparobustdepay", 0,
+ "Robust MPEG Audio RTP Depayloader");
+}
+
+static void
+gst_rtp_mpa_robust_depay_init (GstRtpMPARobustDepay * rtpmpadepay,
+ GstRtpMPARobustDepayClass * klass)
+{
+ rtpmpadepay->adapter = gst_adapter_new ();
+ rtpmpadepay->adu_frames = g_queue_new ();
+}
+
+static gboolean
+gst_rtp_mpa_robust_depay_setcaps (GstBaseRTPDepayload * depayload,
+ GstCaps * caps)
+{
+ GstRtpMPARobustDepay *rtpmpadepay;
+ GstStructure *structure;
+ GstCaps *outcaps;
+ gint clock_rate, draft;
+ gboolean res;
+ const gchar *encoding;
+
+ rtpmpadepay = GST_RTP_MPA_ROBUST_DEPAY (depayload);
+
+ structure = gst_caps_get_structure (caps, 0);
+
+ if (!gst_structure_get_int (structure, "clock-rate", &clock_rate))
+ clock_rate = 90000;
+ depayload->clock_rate = clock_rate;
+
+ rtpmpadepay->has_descriptor = TRUE;
+ if ((encoding = gst_structure_get_string (structure, "encoding-name"))) {
+ if (sscanf (encoding, "X-MP3-DRAFT-%d", &draft) && (draft == 0))
+ rtpmpadepay->has_descriptor = FALSE;
+ }
+
+ outcaps =
+ gst_caps_new_simple ("audio/mpeg", "mpegversion", G_TYPE_INT, 1, NULL);
+ res = gst_pad_set_caps (depayload->srcpad, outcaps);
+ gst_caps_unref (outcaps);
+
+ return res;
+}
+
+/* thanks again go to mp3parse ... */
+
+static const guint mp3types_bitrates[2][3][16] = {
+ {
+ {0, 32, 64, 96, 128, 160, 192, 224, 256, 288, 320, 352, 384, 416, 448,},
+ {0, 32, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 384,},
+ {0, 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320,}
+ },
+ {
+ {0, 32, 48, 56, 64, 80, 96, 112, 128, 144, 160, 176, 192, 224, 256,},
+ {0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160,},
+ {0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160,}
+ },
+};
+
+static const guint mp3types_freqs[3][3] = { {44100, 48000, 32000},
+{22050, 24000, 16000},
+{11025, 12000, 8000}
+};
+
+static inline guint
+mp3_type_frame_length_from_header (GstElement * mp3parse, guint32 header,
+ guint * put_version, guint * put_layer, guint * put_channels,
+ guint * put_bitrate, guint * put_samplerate, guint * put_mode,
+ guint * put_crc)
+{
+ guint length;
+ gulong mode, samplerate, bitrate, layer, channels, padding, crc;
+ gulong version;
+ gint lsf, mpg25;
+
+ if (header & (1 << 20)) {
+ lsf = (header & (1 << 19)) ? 0 : 1;
+ mpg25 = 0;
+ } else {
+ lsf = 1;
+ mpg25 = 1;
+ }
+
+ version = 1 + lsf + mpg25;
+
+ layer = 4 - ((header >> 17) & 0x3);
+
+ crc = (header >> 16) & 0x1;
+
+ bitrate = (header >> 12) & 0xF;
+ bitrate = mp3types_bitrates[lsf][layer - 1][bitrate] * 1000;
+ /* The caller has ensured we have a valid header, so bitrate can't be
+ zero here. */
+ if (bitrate == 0)
+ return 0;
+
+ samplerate = (header >> 10) & 0x3;
+ samplerate = mp3types_freqs[lsf + mpg25][samplerate];
+
+ padding = (header >> 9) & 0x1;
+
+ mode = (header >> 6) & 0x3;
+ channels = (mode == 3) ? 1 : 2;
+
+ switch (layer) {
+ case 1:
+ length = 4 * ((bitrate * 12) / samplerate + padding);
+ break;
+ case 2:
+ length = (bitrate * 144) / samplerate + padding;
+ break;
+ default:
+ case 3:
+ length = (bitrate * 144) / (samplerate << lsf) + padding;
+ break;
+ }
+
+ GST_LOG_OBJECT (mp3parse, "Calculated mp3 frame length of %u bytes", length);
+ GST_LOG_OBJECT (mp3parse, "samplerate = %lu, bitrate = %lu, version = %lu, "
+ "layer = %lu, channels = %lu, mode = %lu", samplerate, bitrate, version,
+ layer, channels, mode);
+
+ if (put_version)
+ *put_version = version;
+ if (put_layer)
+ *put_layer = layer;
+ if (put_channels)
+ *put_channels = channels;
+ if (put_bitrate)
+ *put_bitrate = bitrate;
+ if (put_samplerate)
+ *put_samplerate = samplerate;
+ if (put_mode)
+ *put_mode = mode;
+ if (put_crc)
+ *put_crc = crc;
+
+ return length;
+}
+
+/* generate empty/silent/dummy frame that mimics @frame,
+ * except for rate, where maximum possible is selected */
+static GstADUFrame *
+gst_rtp_mpa_robust_depay_generate_dummy_frame (GstRtpMPARobustDepay *
+ rtpmpadepay, GstADUFrame * frame)
+{
+ GstADUFrame *dummy;
+
+ dummy = g_slice_dup (GstADUFrame, frame);
+
+ /* go for maximum bitrate */
+ dummy->header = frame->header | (0xf << 12);
+ dummy->size =
+ mp3_type_frame_length_from_header (GST_ELEMENT_CAST (rtpmpadepay),
+ dummy->header, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
+ dummy->data_size = dummy->size - dummy->side_info;
+ dummy->backpointer = 0;
+
+ dummy->buffer = gst_buffer_new_and_alloc (dummy->size);
+ memset (GST_BUFFER_DATA (dummy->buffer), 0, dummy->size);
+ GST_WRITE_UINT32_BE (GST_BUFFER_DATA (dummy->buffer), dummy->header);
+ GST_BUFFER_TIMESTAMP (dummy->buffer) = GST_BUFFER_TIMESTAMP (frame->buffer);
+
+ return dummy;
+}
+
+/* validates and parses @buf, and queues for further transformation if valid,
+ * otherwise discards @buf
+ * Takes ownership of @buf. */
+static gboolean
+gst_rtp_mpa_robust_depay_queue_frame (GstRtpMPARobustDepay * rtpmpadepay,
+ GstBuffer * buf)
+{
+ GstADUFrame *frame = NULL;
+ guint version, layer, channels, size;
+ guint crc;
+
+ g_return_val_if_fail (buf != NULL, FALSE);
+
+ if (GST_BUFFER_SIZE (buf) < 6) {
+ goto corrupt_frame;
+ }
+
+ frame = g_slice_new0 (GstADUFrame);
+ frame->header = GST_READ_UINT32_BE (GST_BUFFER_DATA (buf));
+
+ size = mp3_type_frame_length_from_header (GST_ELEMENT_CAST (rtpmpadepay),
+ frame->header, &version, &layer, &channels, NULL, NULL, NULL, &crc);
+ if (!size)
+ goto corrupt_frame;
+
+ frame->size = size;
+ frame->layer = layer;
+ if (version == 1 && channels == 2)
+ frame->side_info = 32;
+ else if ((version == 1 && channels == 1) || (version >= 2 && channels == 2))
+ frame->side_info = 17;
+ else if (version >= 2 && channels == 1)
+ frame->side_info = 9;
+ else {
+ g_assert_not_reached ();
+ goto corrupt_frame;
+ }
+
+ /* backpointer */
+ if (layer == 3) {
+ frame->backpointer = GST_READ_UINT16_BE (GST_BUFFER_DATA (buf) + 4);
+ frame->backpointer >>= 7;
+ GST_LOG_OBJECT (rtpmpadepay, "backpointer: %d", frame->backpointer);
+ }
+
+ if (crc)
+ frame->side_info += 2;
+
+ GST_LOG_OBJECT (rtpmpadepay, "side info: %d", frame->side_info);
+ frame->data_size = frame->size - 4 - frame->side_info;
+
+ /* some size validation checks */
+ if (4 + frame->side_info > GST_BUFFER_SIZE (buf))
+ goto corrupt_frame;
+
+ /* ADU data would then extend past MP3 frame,
+ * even using past byte reservoir */
+ if (-frame->backpointer + GST_BUFFER_SIZE (buf) > frame->size)
+ goto corrupt_frame;
+
+ /* ok, take buffer and queue */
+ frame->buffer = buf;
+ g_queue_push_tail (rtpmpadepay->adu_frames, frame);
+
+ return TRUE;
+
+ /* ERRORS */
+corrupt_frame:
+ {
+ GST_DEBUG_OBJECT (rtpmpadepay, "frame is corrupt");
+ gst_buffer_unref (buf);
+ if (frame)
+ g_slice_free (GstADUFrame, frame);
+ return FALSE;
+ }
+}
+
+static inline void
+gst_rtp_mpa_robust_depay_free_frame (GstADUFrame * frame)
+{
+ if (frame->buffer)
+ gst_buffer_unref (frame->buffer);
+ g_slice_free (GstADUFrame, frame);
+}
+
+static inline void
+gst_rtp_mpa_robust_depay_dequeue_frame (GstRtpMPARobustDepay * rtpmpadepay)
+{
+ GstADUFrame *head;
+
+ GST_LOG_OBJECT (rtpmpadepay, "dequeueing ADU frame");
+
+ if (rtpmpadepay->adu_frames->head == rtpmpadepay->cur_adu_frame)
+ rtpmpadepay->cur_adu_frame = NULL;
+
+ head = g_queue_pop_head (rtpmpadepay->adu_frames);
+ g_assert (head->buffer);
+ gst_rtp_mpa_robust_depay_free_frame (head);
+
+ return;
+}
+
+/* returns TRUE if at least one new ADU frame was enqueued for MP3 conversion.
+ * Takes ownership of @buf. */
+static gboolean
+gst_rtp_mpa_robust_depay_deinterleave (GstRtpMPARobustDepay * rtpmpadepay,
+ GstBuffer * buf)
+{
+ gboolean ret = FALSE;
+ guint8 *data;
+ guint val, iindex, icc;
+
+ data = GST_BUFFER_DATA (buf);
+ val = GST_READ_UINT16_BE (data) >> 5;
+ iindex = val >> 3;
+ icc = val & 0x7;
+
+ GST_LOG_OBJECT (rtpmpadepay, "sync: 0x%x, index: %u, cycle count: %u",
+ val, iindex, icc);
+
+ /* basic case; no interleaving ever seen */
+ if (val == 0x7ff && rtpmpadepay->last_icc < 0) {
+ ret = gst_rtp_mpa_robust_depay_queue_frame (rtpmpadepay, buf);
+ } else {
+ if (G_UNLIKELY (rtpmpadepay->last_icc < 0)) {
+ rtpmpadepay->last_icc = icc;
+ rtpmpadepay->last_ii = iindex;
+ }
+ if (icc != rtpmpadepay->last_icc || iindex == rtpmpadepay->last_ii) {
+ gint i;
+
+ for (i = 0; i < 256; ++i) {
+ if (rtpmpadepay->deinter[i] != NULL) {
+ ret |= gst_rtp_mpa_robust_depay_queue_frame (rtpmpadepay,
+ rtpmpadepay->deinter[i]);
+ rtpmpadepay->deinter[i] = NULL;
+ }
+ }
+ }
+ /* rewrite buffer sync header */
+ val = GST_READ_UINT16_BE (buf);
+ val = (0x7ff << 5) | val;
+ GST_WRITE_UINT16_BE (buf, val);
+ /* store and keep track of last indices */
+ rtpmpadepay->last_icc = icc;
+ rtpmpadepay->last_ii = iindex;
+ rtpmpadepay->deinter[iindex] = buf;
+ }
+
+ return ret;
+}
+
+/* Head ADU frame corresponds to mp3_frame (i.e. in header in side-info) that
+ * is currently being written
+ * cur_adu_frame refers to ADU frame whose data should be bytewritten next
+ * (possibly starting from offset rather than start 0) (and is typicall tail
+ * at time of last push round).
+ * If at start, position where it should start writing depends on (data) sizes
+ * of previous mp3 frames (corresponding to foregoing ADU frames) kept in size,
+ * and its backpointer */
+static GstFlowReturn
+gst_rtp_mpa_robust_depay_push_mp3_frames (GstRtpMPARobustDepay * rtpmpadepay)
+{
+ GstBuffer *buf;
+ GstADUFrame *frame, *head;
+ gint av;
+ GstFlowReturn ret = GST_FLOW_OK;
+
+ while (1) {
+
+ if (G_UNLIKELY (!rtpmpadepay->cur_adu_frame)) {
+ rtpmpadepay->cur_adu_frame = rtpmpadepay->adu_frames->head;
+ rtpmpadepay->offset = 0;
+ rtpmpadepay->size = 0;
+ }
+
+ if (G_UNLIKELY (!rtpmpadepay->cur_adu_frame))
+ break;
+
+ frame = (GstADUFrame *) rtpmpadepay->cur_adu_frame->data;
+ head = (GstADUFrame *) rtpmpadepay->adu_frames->head->data;
+
+ /* special case: non-layer III are sent straight through */
+ if (G_UNLIKELY (frame->layer != 3)) {
+ GST_DEBUG_OBJECT (rtpmpadepay, "layer %d frame, sending as-is",
+ frame->layer);
+ gst_base_rtp_depayload_push (GST_BASE_RTP_DEPAYLOAD (rtpmpadepay),
+ frame->buffer);
+ frame->buffer = NULL;
+ /* and remove it from any further consideration */
+ g_slice_free (GstADUFrame, frame);
+ g_queue_delete_link (rtpmpadepay->adu_frames, rtpmpadepay->cur_adu_frame);
+ rtpmpadepay->cur_adu_frame = NULL;
+ continue;
+ }
+
+ if (rtpmpadepay->offset == GST_BUFFER_SIZE (frame->buffer)) {
+ if (g_list_next (rtpmpadepay->cur_adu_frame)) {
+ GST_LOG_OBJECT (rtpmpadepay,
+ "moving to next ADU frame, size %d, side_info %d",
+ frame->size, frame->side_info);
+ rtpmpadepay->size += frame->data_size;
+ rtpmpadepay->cur_adu_frame = g_list_next (rtpmpadepay->cur_adu_frame);
+ frame = (GstADUFrame *) rtpmpadepay->cur_adu_frame->data;
+ rtpmpadepay->offset = 0;
+ /* layer I and II packets have no bitreservoir and must be sent as-is;
+ * so flush any pending frame */
+ if (G_UNLIKELY (frame->layer != 3 && rtpmpadepay->mp3_frame))
+ goto flush;
+ } else {
+ break;
+ }
+ }
+
+ if (G_UNLIKELY (!rtpmpadepay->mp3_frame)) {
+ GST_LOG_OBJECT (rtpmpadepay,
+ "setting up new MP3 frame of size %d, side_info %d",
+ head->size, head->side_info);
+ rtpmpadepay->mp3_frame = gst_byte_writer_new_with_size (head->size, TRUE);
+ /* 0-fill possible gaps */
+ gst_byte_writer_fill (rtpmpadepay->mp3_frame, 0, head->size);
+ gst_byte_writer_set_pos (rtpmpadepay->mp3_frame, 0);
+ /* bytewriter corresponds to head frame,
+ * i.e. the header and the side info must match */
+ gst_byte_writer_put_data (rtpmpadepay->mp3_frame,
+ GST_BUFFER_DATA (head->buffer), 4 + head->side_info);
+ }
+
+ buf = frame->buffer;
+ av = gst_byte_writer_get_remaining (rtpmpadepay->mp3_frame);
+ GST_LOG_OBJECT (rtpmpadepay, "current mp3 frame remaining: %d", av);
+ GST_LOG_OBJECT (rtpmpadepay, "accumulated ADU frame data_size: %d",
+ rtpmpadepay->size);
+
+ if (rtpmpadepay->offset) {
+ /* no need to position, simply append */
+ g_assert (GST_BUFFER_SIZE (buf) > rtpmpadepay->offset);
+ av = MIN (av, GST_BUFFER_SIZE (buf) - rtpmpadepay->offset);
+ GST_LOG_OBJECT (rtpmpadepay,
+ "appending %d bytes from ADU frame at offset %d", av,
+ rtpmpadepay->offset);
+ gst_byte_writer_put_data (rtpmpadepay->mp3_frame,
+ GST_BUFFER_DATA (buf) + rtpmpadepay->offset, av);
+ rtpmpadepay->offset += av;
+ } else {
+ gint pos, tpos;
+
+ /* position writing according to ADU frame backpointer */
+ pos = gst_byte_writer_get_pos (rtpmpadepay->mp3_frame);
+ tpos = rtpmpadepay->size - frame->backpointer + 4 + head->side_info;
+ GST_LOG_OBJECT (rtpmpadepay, "current MP3 frame at position %d, "
+ "starting new ADU frame data at offset %d", pos, tpos);
+ if (tpos < pos) {
+ GstADUFrame *dummy;
+
+ /* try to insert as few frames as possible,
+ * so go for a reasonably large dummy frame size */
+ GST_LOG_OBJECT (rtpmpadepay,
+ "overlapping previous data; inserting dummy frame");
+ dummy =
+ gst_rtp_mpa_robust_depay_generate_dummy_frame (rtpmpadepay, frame);
+ g_queue_insert_before (rtpmpadepay->adu_frames,
+ rtpmpadepay->cur_adu_frame, dummy);
+ /* offset is known to be zero, so we can shift current one */
+ rtpmpadepay->cur_adu_frame = rtpmpadepay->cur_adu_frame->prev;
+ /* ... and continue adding that empty one immediately,
+ * and then see if that provided enough extra space */
+ continue;
+ } else if (tpos >= pos + av) {
+ /* ADU frame no longer needs current MP3 frame; move to its end */
+ GST_LOG_OBJECT (rtpmpadepay, "passed current MP3 frame");
+ gst_byte_writer_set_pos (rtpmpadepay->mp3_frame, pos + av);
+ } else {
+ /* position and append */
+ GST_LOG_OBJECT (rtpmpadepay, "adding to current MP3 frame");
+ gst_byte_writer_set_pos (rtpmpadepay->mp3_frame, tpos);
+ av = MIN (av, GST_BUFFER_SIZE (buf) - 4 - frame->side_info);
+ gst_byte_writer_put_data (rtpmpadepay->mp3_frame,
+ GST_BUFFER_DATA (buf) + 4 + frame->side_info, av);
+ rtpmpadepay->offset += av + 4 + frame->side_info;
+ }
+ }
+
+ /* if mp3 frame filled, send on its way */
+ if (gst_byte_writer_get_remaining (rtpmpadepay->mp3_frame) == 0) {
+ flush:
+ buf = gst_byte_writer_free_and_get_buffer (rtpmpadepay->mp3_frame);
+ rtpmpadepay->mp3_frame = NULL;
+ GST_BUFFER_TIMESTAMP (buf) = GST_BUFFER_TIMESTAMP (head->buffer);
+ /* no longer need head ADU frame header and side info */
+ /* NOTE maybe head == current, then size and offset go off a bit,
+ * but current gets reset to NULL, and then also offset and size */
+ rtpmpadepay->size -= head->data_size;
+ gst_rtp_mpa_robust_depay_dequeue_frame (rtpmpadepay);
+ /* send */
+ ret = gst_base_rtp_depayload_push (GST_BASE_RTP_DEPAYLOAD (rtpmpadepay),
+ buf);
+ }
+ }
+
+ return ret;
+}
+
+/* process ADU frame @buf through:
+ * - deinterleaving
+ * - converting to MP3 frames
+ * Takes ownership of @buf.
+ */
+static GstFlowReturn
+gst_rtp_mpa_robust_depay_submit_adu (GstRtpMPARobustDepay * rtpmpadepay,
+ GstBuffer * buf)
+{
+ if (gst_rtp_mpa_robust_depay_deinterleave (rtpmpadepay, buf))
+ return gst_rtp_mpa_robust_depay_push_mp3_frames (rtpmpadepay);
+
+ return GST_FLOW_OK;
+}
+
+static GstBuffer *
+gst_rtp_mpa_robust_depay_process (GstBaseRTPDepayload * depayload,
+ GstBuffer * buf)
+{
+ GstRtpMPARobustDepay *rtpmpadepay;
+ gint payload_len, offset;
+ guint8 *payload;
+ gboolean cont, dtype;
+ guint av, size;
+ GstClockTime timestamp;
+
+ rtpmpadepay = GST_RTP_MPA_ROBUST_DEPAY (depayload);
+
+ payload_len = gst_rtp_buffer_get_payload_len (buf);
+ timestamp = GST_BUFFER_TIMESTAMP (buf);
+
+ if (payload_len <= 1)
+ goto short_read;
+
+ payload = gst_rtp_buffer_get_payload (buf);
+ offset = 0;
+ GST_LOG_OBJECT (rtpmpadepay, "payload_len: %d", payload_len);
+
+ /* strip off descriptor
+ *
+ * 0 1
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |C|T| ADU size |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * C: if 1, data is continuation
+ * T: if 1, size is 14 bits, otherwise 6 bits
+ * ADU size: size of following packet (not including descriptor)
+ */
+ while (payload_len) {
+ if (G_LIKELY (rtpmpadepay->has_descriptor)) {
+ cont = !!(payload[offset] & 0x80);
+ dtype = !!(payload[offset] & 0x40);
+ if (dtype) {
+ size = (payload[offset] & 0x3f) << 8 | payload[offset + 1];
+ payload_len--;
+ offset++;
+ } else if (payload_len >= 2) {
+ size = (payload[offset] & 0x3f);
+ payload_len -= 2;
+ offset += 2;
+ } else {
+ goto short_read;
+ }
+ } else {
+ cont = FALSE;
+ dtype = -1;
+ size = payload_len;
+ }
+
+ GST_LOG_OBJECT (rtpmpadepay, "offset %d has cont: %d, dtype: %d, size: %d",
+ offset, cont, dtype, size);
+
+ buf = gst_rtp_buffer_get_payload_subbuffer (buf, offset,
+ MIN (size, payload_len));
+
+ if (cont) {
+ av = gst_adapter_available (rtpmpadepay->adapter);
+ if (G_UNLIKELY (!av)) {
+ GST_DEBUG_OBJECT (rtpmpadepay,
+ "discarding continuation fragment without prior fragment");
+ gst_buffer_unref (buf);
+ } else {
+ av += GST_BUFFER_SIZE (buf);
+ gst_adapter_push (rtpmpadepay->adapter, buf);
+ if (av == size) {
+ timestamp = gst_adapter_prev_timestamp (rtpmpadepay->adapter, NULL);
+ buf = gst_adapter_take_buffer (rtpmpadepay->adapter, size);
+ GST_BUFFER_TIMESTAMP (buf) = timestamp;
+ gst_rtp_mpa_robust_depay_submit_adu (rtpmpadepay, buf);
+ } else if (av > size) {
+ GST_DEBUG_OBJECT (rtpmpadepay,
+ "assembled ADU size %d larger than expected %d; discarding",
+ av, size);
+ gst_adapter_clear (rtpmpadepay->adapter);
+ }
+ }
+ size = payload_len;
+ } else {
+ /* not continuation, first fragment or whole ADU */
+ if (payload_len == size) {
+ /* whole ADU */
+ GST_BUFFER_TIMESTAMP (buf) = timestamp;
+ gst_rtp_mpa_robust_depay_submit_adu (rtpmpadepay, buf);
+ } else if (payload_len < size) {
+ /* first fragment */
+ gst_adapter_push (rtpmpadepay->adapter, buf);
+ size = payload_len;
+ }
+ }
+
+ offset += size;
+ payload_len -= size;
+
+ /* timestamp applies to first payload, no idea for subsequent ones */
+ timestamp = GST_CLOCK_TIME_NONE;
+ }
+
+ return NULL;
+
+ /* ERRORS */
+short_read:
+ {
+ GST_ELEMENT_WARNING (rtpmpadepay, STREAM, DECODE,
+ (NULL), ("Packet contains invalid data"));
+ return NULL;
+ }
+}
+
+static GstStateChangeReturn
+gst_rtp_mpa_robust_change_state (GstElement * element,
+ GstStateChange transition)
+{
+ GstStateChangeReturn ret;
+ GstRtpMPARobustDepay *rtpmpadepay;
+
+ rtpmpadepay = GST_RTP_MPA_ROBUST_DEPAY (element);
+
+ switch (transition) {
+ case GST_STATE_CHANGE_READY_TO_PAUSED:
+ rtpmpadepay->last_ii = -1;
+ rtpmpadepay->last_icc = -1;
+ rtpmpadepay->size = 0;
+ rtpmpadepay->offset = 0;
+ default:
+ break;
+ }
+
+ ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
+ if (ret != GST_STATE_CHANGE_SUCCESS)
+ return ret;
+
+ switch (transition) {
+ case GST_STATE_CHANGE_PAUSED_TO_READY:
+ {
+ gint i;
+
+ gst_adapter_clear (rtpmpadepay->adapter);
+ for (i = 0; i < G_N_ELEMENTS (rtpmpadepay->deinter); i++) {
+ gst_buffer_unref (rtpmpadepay->deinter[i]);
+ rtpmpadepay->deinter[i] = NULL;
+ }
+ rtpmpadepay->cur_adu_frame = NULL;
+ g_queue_foreach (rtpmpadepay->adu_frames,
+ (GFunc) gst_rtp_mpa_robust_depay_free_frame, NULL);
+ g_queue_clear (rtpmpadepay->adu_frames);
+ break;
+ }
+ default:
+ break;
+ }
+
+ return ret;
+}
+
+gboolean
+gst_rtp_mpa_robust_depay_plugin_init (GstPlugin * plugin)
+{
+ return gst_element_register (plugin, "rtpmparobustdepay",
+ GST_RANK_MARGINAL, GST_TYPE_RTP_MPA_ROBUST_DEPAY);
+}