summaryrefslogtreecommitdiff
path: root/gst/rtp/gstrtpdvdepay.c
diff options
context:
space:
mode:
Diffstat (limited to 'gst/rtp/gstrtpdvdepay.c')
-rwxr-xr-xgst/rtp/gstrtpdvdepay.c415
1 files changed, 415 insertions, 0 deletions
diff --git a/gst/rtp/gstrtpdvdepay.c b/gst/rtp/gstrtpdvdepay.c
new file mode 100755
index 0000000..f13b696
--- /dev/null
+++ b/gst/rtp/gstrtpdvdepay.c
@@ -0,0 +1,415 @@
+/* Farsight
+ * Copyright (C) 2006 Marcel Moreaux <marcelm@spacelabs.nl>
+ * (C) 2008 Wim Taymans <wim.taymans@gmail.com>
+ *
+ * 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.
+ */
+
+/*
+ * RTP DV depayloader.
+ *
+ * Important note for NTSC-users:
+ *
+ * Because the author uses PAL video, and he does not have proper DV
+ * documentation (the DV format specification is not freely available),
+ * this code may very well contain PAL-specific assumptions.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <gst/gst.h>
+
+#include "gstrtpdvdepay.h"
+
+GST_DEBUG_CATEGORY (rtpdvdepay_debug);
+#define GST_CAT_DEFAULT (rtpdvdepay_debug)
+/* Filter signals and args */
+enum
+{
+ /* FILL ME */
+ LAST_SIGNAL
+};
+
+enum
+{
+ PROP_0,
+};
+
+static GstStaticPadTemplate src_factory = GST_STATIC_PAD_TEMPLATE ("src",
+ GST_PAD_SRC,
+ GST_PAD_ALWAYS,
+ GST_STATIC_CAPS ("video/x-dv")
+ );
+
+static GstStaticPadTemplate sink_factory = GST_STATIC_PAD_TEMPLATE ("sink",
+ GST_PAD_SINK,
+ GST_PAD_ALWAYS,
+ GST_STATIC_CAPS ("application/x-rtp, "
+ "media = (string) { \"video\", \"audio\" },"
+ "encoding-name = (string) \"DV\", "
+ "clock-rate = (int) 90000,"
+ "encode = (string) { \"SD-VCR/525-60\", \"SD-VCR/625-50\", \"HD-VCR/1125-60\","
+ "\"HD-VCR/1250-50\", \"SDL-VCR/525-60\", \"SDL-VCR/625-50\","
+ "\"306M/525-60\", \"306M/625-50\", \"314M-25/525-60\","
+ "\"314M-25/625-50\", \"314M-50/525-60\", \"314M-50/625-50\" }"
+ /* optional parameters can't go in the template
+ * "audio = (string) { \"bundled\", \"none\" }"
+ */
+ )
+ );
+
+static GstStateChangeReturn
+gst_rtp_dv_depay_change_state (GstElement * element, GstStateChange transition);
+
+static GstBuffer *gst_rtp_dv_depay_process (GstRTPBaseDepayload * base,
+ GstBuffer * in);
+static gboolean gst_rtp_dv_depay_setcaps (GstRTPBaseDepayload * depayload,
+ GstCaps * caps);
+
+#define gst_rtp_dv_depay_parent_class parent_class
+G_DEFINE_TYPE (GstRTPDVDepay, gst_rtp_dv_depay, GST_TYPE_RTP_BASE_DEPAYLOAD);
+
+
+static void
+gst_rtp_dv_depay_class_init (GstRTPDVDepayClass * klass)
+{
+ GstElementClass *gstelement_class = (GstElementClass *) klass;
+ GstRTPBaseDepayloadClass *gstrtpbasedepayload_class =
+ (GstRTPBaseDepayloadClass *) klass;
+
+ GST_DEBUG_CATEGORY_INIT (rtpdvdepay_debug, "rtpdvdepay", 0,
+ "DV RTP Depayloader");
+
+ gstelement_class->change_state =
+ GST_DEBUG_FUNCPTR (gst_rtp_dv_depay_change_state);
+
+ gst_element_class_add_pad_template (gstelement_class,
+ gst_static_pad_template_get (&src_factory));
+ gst_element_class_add_pad_template (gstelement_class,
+ gst_static_pad_template_get (&sink_factory));
+
+ gst_element_class_set_static_metadata (gstelement_class, "RTP DV Depayloader",
+ "Codec/Depayloader/Network/RTP",
+ "Depayloads DV from RTP packets (RFC 3189)",
+ "Marcel Moreaux <marcelm@spacelabs.nl>, Wim Taymans <wim.taymans@gmail.com>");
+
+ gstrtpbasedepayload_class->process =
+ GST_DEBUG_FUNCPTR (gst_rtp_dv_depay_process);
+ gstrtpbasedepayload_class->set_caps =
+ GST_DEBUG_FUNCPTR (gst_rtp_dv_depay_setcaps);
+}
+
+/* initialize the new element
+ * instantiate pads and add them to element
+ * set functions
+ * initialize structure
+ */
+static void
+gst_rtp_dv_depay_init (GstRTPDVDepay * filter)
+{
+}
+
+static gboolean
+parse_encode (GstRTPDVDepay * rtpdvdepay, const gchar * encode)
+{
+ rtpdvdepay->width = 720;
+ if (!strcmp (encode, "314M-25/525-60")) {
+ rtpdvdepay->frame_size = 240000;
+ rtpdvdepay->height = 480;
+ rtpdvdepay->rate_num = 30000;
+ rtpdvdepay->rate_denom = 1001;
+ } else if (!strcmp (encode, "SD-VCR/525-60")) {
+ rtpdvdepay->frame_size = 120000;
+ rtpdvdepay->height = 480;
+ rtpdvdepay->rate_num = 30000;
+ rtpdvdepay->rate_denom = 1001;
+ } else if (!strcmp (encode, "314M-50/625-50")) {
+ rtpdvdepay->frame_size = 288000;
+ rtpdvdepay->height = 576;
+ rtpdvdepay->rate_num = 25;
+ rtpdvdepay->rate_denom = 1;
+ } else if (!strcmp (encode, "SD-VCR/625-50")) {
+ rtpdvdepay->frame_size = 144000;
+ rtpdvdepay->height = 576;
+ rtpdvdepay->rate_num = 25;
+ rtpdvdepay->rate_denom = 1;
+ } else if (!strcmp (encode, "314M-25/625-50")) {
+ rtpdvdepay->frame_size = 144000;
+ rtpdvdepay->height = 576;
+ rtpdvdepay->rate_num = 25;
+ rtpdvdepay->rate_denom = 1;
+ } else
+ rtpdvdepay->frame_size = -1;
+
+ return rtpdvdepay->frame_size != -1;
+}
+
+static gboolean
+gst_rtp_dv_depay_setcaps (GstRTPBaseDepayload * depayload, GstCaps * caps)
+{
+ GstStructure *structure;
+ GstRTPDVDepay *rtpdvdepay;
+ GstCaps *srccaps;
+ gint clock_rate;
+ gboolean systemstream, ret;
+ const gchar *encode, *media;
+
+ rtpdvdepay = GST_RTP_DV_DEPAY (depayload);
+
+ structure = gst_caps_get_structure (caps, 0);
+
+ if (!gst_structure_get_int (structure, "clock-rate", &clock_rate))
+ clock_rate = 90000; /* default */
+ depayload->clock_rate = clock_rate;
+
+ /* we really need the encode property to figure out the frame size, it's also
+ * required by the spec */
+ if (!(encode = gst_structure_get_string (structure, "encode")))
+ goto no_encode;
+
+ /* figure out the size of one frame */
+ if (!parse_encode (rtpdvdepay, encode))
+ goto unknown_encode;
+
+ /* check the media, this tells us that the stream has video or not */
+ if (!(media = gst_structure_get_string (structure, "media")))
+ goto no_media;
+
+ systemstream = FALSE;
+
+ if (!strcmp (media, "audio")) {
+ /* we need a demuxer for audio only */
+ systemstream = TRUE;
+ } else if (!strcmp (media, "video")) {
+ const gchar *audio;
+
+ /* check the optional audio field, if it's present and set to bundled, we
+ * are dealing with a system stream. */
+ if ((audio = gst_structure_get_string (structure, "audio"))) {
+ if (!strcmp (audio, "bundled"))
+ systemstream = TRUE;
+ }
+ }
+
+ /* allocate accumulator */
+ rtpdvdepay->acc = gst_buffer_new_and_alloc (rtpdvdepay->frame_size);
+
+ /* Initialize the new accumulator frame.
+ * If the previous frame exists, copy that into the accumulator frame.
+ * This way, missing packets in the stream won't show up badly. */
+ gst_buffer_memset (rtpdvdepay->acc, 0, 0, rtpdvdepay->frame_size);
+
+ srccaps = gst_caps_new_simple ("video/x-dv",
+ "systemstream", G_TYPE_BOOLEAN, systemstream,
+ "width", G_TYPE_INT, rtpdvdepay->width,
+ "height", G_TYPE_INT, rtpdvdepay->height,
+ "framerate", GST_TYPE_FRACTION, rtpdvdepay->rate_num,
+ rtpdvdepay->rate_denom, NULL);
+ ret = gst_pad_set_caps (depayload->srcpad, srccaps);
+ gst_caps_unref (srccaps);
+
+ return ret;
+
+ /* ERRORS */
+no_encode:
+ {
+ GST_ERROR_OBJECT (rtpdvdepay, "required encode property not found in caps");
+ return FALSE;
+ }
+unknown_encode:
+ {
+ GST_ERROR_OBJECT (rtpdvdepay, "unknown encode property %s found", encode);
+ return FALSE;
+ }
+no_media:
+ {
+ GST_ERROR_OBJECT (rtpdvdepay, "required media property not found in caps");
+ return FALSE;
+ }
+}
+
+/* A DV frame consists of a bunch of 80-byte DIF blocks.
+ * Each DIF block contains a 3-byte header telling where in the DV frame the
+ * DIF block should go. We use this information to calculate its position.
+ */
+static guint
+calculate_difblock_location (guint8 * block)
+{
+ gint block_type, dif_sequence, dif_block;
+ guint location;
+
+ block_type = block[0] >> 5;
+ dif_sequence = block[1] >> 4;
+ dif_block = block[2];
+
+ location = dif_sequence * 150;
+
+ switch (block_type) {
+ case 0: /* Header block, no offset */
+ break;
+ case 1: /* Subcode block */
+ location += (1 + dif_block);
+ break;
+ case 2: /* VAUX block */
+ location += (3 + dif_block);
+ break;
+ case 3: /* Audio block */
+ location += (6 + dif_block * 16);
+ break;
+ case 4: /* Video block */
+ location += (7 + (dif_block / 15) + dif_block);
+ break;
+ default: /* Something bogus */
+ GST_DEBUG ("UNKNOWN BLOCK");
+ location = -1;
+ break;
+ }
+ return location;
+}
+
+/* Process one RTP packet. Accumulate RTP payload in the proper place in a DV
+ * frame, and return that frame if we detect a new frame, or NULL otherwise.
+ * We assume a DV frame is 144000 bytes. That should accomodate PAL as well as
+ * NTSC.
+ */
+static GstBuffer *
+gst_rtp_dv_depay_process (GstRTPBaseDepayload * base, GstBuffer * in)
+{
+ GstBuffer *out = NULL;
+ guint8 *payload;
+ guint32 rtp_ts;
+ guint payload_len, location;
+ GstRTPDVDepay *dvdepay = GST_RTP_DV_DEPAY (base);
+ gboolean marker;
+ GstRTPBuffer rtp = { NULL, };
+
+ gst_rtp_buffer_map (in, GST_MAP_READ, &rtp);
+
+ marker = gst_rtp_buffer_get_marker (&rtp);
+
+ /* Check if the received packet contains (the start of) a new frame, we do
+ * this by checking the RTP timestamp. */
+ rtp_ts = gst_rtp_buffer_get_timestamp (&rtp);
+
+ /* we cannot copy the packet yet if the marker is set, we will do that below
+ * after taking out the data */
+ if (dvdepay->prev_ts != -1 && rtp_ts != dvdepay->prev_ts && !marker) {
+ /* the timestamp changed */
+ GST_DEBUG_OBJECT (dvdepay, "new frame with ts %u, old ts %u", rtp_ts,
+ dvdepay->prev_ts);
+
+ /* return copy of accumulator. */
+ out = gst_buffer_copy (dvdepay->acc);
+ }
+
+ /* Extract the payload */
+ payload_len = gst_rtp_buffer_get_payload_len (&rtp);
+ payload = gst_rtp_buffer_get_payload (&rtp);
+
+ /* copy all DIF chunks in their place. */
+ while (payload_len >= 80) {
+ guint offset;
+
+ /* Calculate where in the frame the payload should go */
+ location = calculate_difblock_location (payload);
+
+ if (location < 6) {
+ /* part of a header, set the flag to mark that we have the header. */
+ dvdepay->header_mask |= (1 << location);
+ GST_LOG_OBJECT (dvdepay, "got header at location %d, now %02x", location,
+ dvdepay->header_mask);
+ } else {
+ GST_LOG_OBJECT (dvdepay, "got block at location %d", location);
+ }
+
+ if (location != -1) {
+ /* get the byte offset of the dif block */
+ offset = location * 80;
+
+ /* And copy it in, provided the location is sane. */
+ if (offset <= dvdepay->frame_size - 80)
+ gst_buffer_fill (dvdepay->acc, offset, payload, 80);
+ }
+
+ payload += 80;
+ payload_len -= 80;
+ }
+ gst_rtp_buffer_unmap (&rtp);
+
+ if (marker) {
+ GST_DEBUG_OBJECT (dvdepay, "marker bit complete frame %u", rtp_ts);
+ /* only copy the frame when we have a complete header */
+ if (dvdepay->header_mask == 0x3f) {
+ /* The marker marks the end of a frame that we need to push. The next frame
+ * will change the timestamp but we won't copy the accumulator again because
+ * we set the prev_ts to -1. */
+ out = gst_buffer_copy (dvdepay->acc);
+ } else {
+ GST_WARNING_OBJECT (dvdepay, "waiting for frame headers %02x",
+ dvdepay->header_mask);
+ }
+ dvdepay->prev_ts = -1;
+ } else {
+ /* save last timestamp */
+ dvdepay->prev_ts = rtp_ts;
+ }
+ return out;
+}
+
+static void
+gst_rtp_dv_depay_reset (GstRTPDVDepay * depay)
+{
+ if (depay->acc)
+ gst_buffer_unref (depay->acc);
+ depay->acc = NULL;
+
+ depay->prev_ts = -1;
+ depay->header_mask = 0;
+}
+
+static GstStateChangeReturn
+gst_rtp_dv_depay_change_state (GstElement * element, GstStateChange transition)
+{
+ GstStateChangeReturn ret;
+ GstRTPDVDepay *depay = GST_RTP_DV_DEPAY (element);
+
+ switch (transition) {
+ case GST_STATE_CHANGE_READY_TO_PAUSED:
+ gst_rtp_dv_depay_reset (depay);
+ break;
+ default:
+ break;
+ }
+
+ ret = GST_CALL_PARENT_WITH_DEFAULT (GST_ELEMENT_CLASS, change_state,
+ (element, transition), GST_STATE_CHANGE_FAILURE);
+
+ switch (transition) {
+ case GST_STATE_CHANGE_PAUSED_TO_READY:
+ gst_rtp_dv_depay_reset (depay);
+ break;
+ default:
+ break;
+ }
+ return ret;
+}
+
+gboolean
+gst_rtp_dv_depay_plugin_init (GstPlugin * plugin)
+{
+ return gst_element_register (plugin, "rtpdvdepay",
+ GST_RANK_SECONDARY, GST_TYPE_RTP_DV_DEPAY);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-24 11:36:10 +0000